Causation is no corelation. All dokters are idiots paid by big pharma, so they will do anything to deprive us from cheap and effective solutions. Supplements and vitamins are essential for your health. The more you take the better of course.
Gys
Beta-carotene, selenium and folic acid - taken up to three times their recommended daily allowance, these supplements are probably harmless. But taken at much higher levels as some supplement manufacturers suggest, these three supplements have now been proven to increase the risk of developing a host of cancers.
"It's not that these nutrients are toxic - they're essential and we need them, but we need them in a certain balance," says Tim Byers, MD, MPH, professor of epidemiology at the Colorado School of Public Health and associate director for prevention and control at the University of Colorado Cancer Center.
Byers is senior author of a commentary recently published in the Journal of the National Cancer Institute that discusses the clinical and policy implications of the increased cancer risk from high dose dietary supplements.
We have a window into less than half of the biology of what these nutrients are doing," Byers says. "We say generalized things about them, calling them an antioxidant or an essential mineral, but true biology turns out to be more complex than that. The effects of these supplements are certainly not limited to the label we give them. And, as we've seen, sometimes the unintended effects include increased cancer risk."
"We need to do a better job as a society in ensuring that the messages people get about value versus risk is accurate for nutritional supplements," Byers says. "My conclusion is that taking high doses of any particular nutrient is more likely to be a bad thing than a good thing."
> Causation is no corelation. All dokters are idiots paid by big pharma, so
> they will do anything to deprive us from cheap and effective solutions.
> Supplements and vitamins are essential for your health. The more you take
> the better of course.
> Gys
> Beta-carotene, selenium and folic acid - taken up to three times their
> recommended daily allowance, these supplements are probably harmless. But
> taken at much higher levels as some supplement manufacturers suggest, these
> three supplements have now been proven to increase the risk of developing a
> host of cancers.
> "It's not that these nutrients are toxic - they're essential and we need
> them, but we need them in a certain balance," says Tim Byers, MD, MPH,
> professor of epidemiology at the Colorado School of Public Health and
> associate director for prevention and control at the University of Colorado
> Cancer Center.
> Byers is senior author of a commentary recently published in the Journal of
> the National Cancer Institute that discusses the clinical and policy
> implications of the increased cancer risk from high dose dietary
> supplements.
> We have a window into less than half of the biology of what these nutrients
> are doing," Byers says. "We say generalized things about them, calling them
> an antioxidant or an essential mineral, but true biology turns out to be
> more complex than that. The effects of these supplements are certainly not
> limited to the label we give them. And, as we've seen, sometimes the
> unintended effects include increased cancer risk."
> "We need to do a better job as a society in ensuring that the messages
> people get about value versus risk is accurate for nutritional supplements,"
> Byers says. "My conclusion is that taking high doses of any particular
> nutrient is more likely to be a bad thing than a good thing."
In the case of folic acid, I've taken far above normal amount of it
daily for the last 6 years with no adverse effects. Apparently it
only affects some people, if that.
> In the case of folic acid, I've taken far above normal amount of it
> daily for the last 6 years with no adverse effects. Apparently it
> only affects some people, if that.
I'd really recommend a tutorial on stats and probability. The data
don't show that Everyone that takes excess (above RDA) of folic acids
has problems, but a significant number do.
Many have made the same claims of smoking and health. Even me in my
younger, smoking days. Do you think that's a valid refutation of the
data on cigarettes.
On May 15, 6:29 pm, "ra...@val.com" <ra...@val.com> wrote:
> > In the case of folic acid, I've taken far above normal amount of it
> > daily for the last 6 years with no adverse effects. Apparently it
> > only affects some people, if that.
> I'd really recommend a tutorial on stats and probability. The data
> don't show that Everyone that takes excess (above RDA) of folic acids
> has problems, but a significant number do.
> Many have made the same claims of smoking and health. Even me in my
> younger, smoking days. Do you think that's a valid refutation of the
> data on cigarettes.
One of the reasons Folic Acid is added to so many things in our diet
is that the food processing they do on our food takes it out, along
with many other vitamins and nutrients. The story goes that they were
made to put back many of them, but it took 30 years to get the FDA to
insist on putting back Folic Acid. I personally doubt that the food
processors are putting back any more than they took out to keep costs
down.
If a 'significant number' are affected by too much Folic Acid, I
too would like to see the statistics on that, or even the anecdotal
information. You see there's a group out there that would be very
happy to have everyone get away from supplements and vitamins, and
they have enough money to cause all kinds of stories to be generated
and spread around.
As it turns out, before I quit I smoked 1.5 packs a day for about 45
years with no cancer, so that's 2 people to begin new statistics.
When you get them compiled, let me know...:)
One review estimated 15.000 additional cancers due to excess folic
acid intake from 1996 - 2000!
Here's some more references:
Cole BF, Baron JA, Sandler RS, et al. Folic acid for the prevention of
colorectal adenomas: a randomized clinical trial. JAMA. 2007;297(21):
2351–2359.
Figueiredo JC, Grau MV, Haile RW, et al. Folic acid and risk of
prostate cancer: results from a randomized clinical trial. J Natl
Cancer Inst. 2009;101(6):432–435.
Kim YI. Role of folate in colon cancer development and progression. J
Nutr. 2003;133(11)(suppl 1):3731S–3739S.
Mason JB. Folate, cancer risk, and the Greek god, Proteus: a tale of
two chameleons. Nutr Rev. 2009;67(4):206–212.
Collin SM, Metcalfe C, Refsum H, et al. Circulating folate, vitamin
B12, homocysteine, vitamin B12 transport proteins, and risk of
prostate cancer: a case-control study, systematic review, and meta-
analysis. Cancer Epidemiol Biomarkers Prev. 2010;19(6):1632–1642.
Lawson KA, Wright ME, Subar A, et al. Multivitamin use and risk of
prostate cancer in the National Institutes of Health-AARP Diet and
Health Study. J Natl Cancer Inst. 2007;99(10):754–764.
Stolzenberg-Solomon RZ, Chang SC, Leitzmann MF, et al. Folate intake,
alcohol use, and postmenopausal breast cancer risk in the Prostate,
Lung, Colorectal, and Ovarian Cancer Screening Trial. Am J Clin Nutr.
2006;83(4):895–904.
> On May 15, 6:29 pm, "ra...@val.com" <ra...@val.com> wrote:
>>> In the case of folic acid, I've taken far above normal amount of it
>>> daily for the last 6 years with no adverse effects. Apparently it
>>> only affects some people, if that.
>> I'd really recommend a tutorial on stats and probability. The data
>> don't show that Everyone that takes excess (above RDA) of folic acids
>> has problems, but a significant number do.
>> Many have made the same claims of smoking and health. Even me in my
>> younger, smoking days. Do you think that's a valid refutation of the
>> data on cigarettes.
> One of the reasons Folic Acid is added to so many things in our diet
> is that the food processing they do on our food takes it out, along
> with many other vitamins and nutrients. The story goes that they were
> made to put back many of them, but it took 30 years to get the FDA to
> insist on putting back Folic Acid. I personally doubt that the food
> processors are putting back any more than they took out to keep costs
> down.
> If a 'significant number' are affected by too much Folic Acid, I
> too would like to see the statistics on that, or even the anecdotal
> information. You see there's a group out there that would be very
> happy to have everyone get away from supplements and vitamins, and
> they have enough money to cause all kinds of stories to be generated
> and spread around.
> As it turns out, before I quit I smoked 1.5 packs a day for about 45
> years with no cancer, so that's 2 people to begin new statistics.
> When you get them compiled, let me know...:)
> Chris
One more: my mother smoked 2 packs of cigarettes a day for over 70 years. No cancer.
M.
"GysdeJongh" <JonghSevenHundredElevenAtPlanet.nl> wrote:
> Causation is no corelation. All dokters are idiots paid by big
> pharma, so they will do anything to deprive us from cheap and
> effective solutions. Supplements and vitamins are essential for your
> health. The more you take the better of course.
> Gys
> Beta-carotene, selenium and folic acid - taken up to three times
> their recommended daily allowance, these supplements are probably
> harmless...
...
> We have a window into less than half of the biology of what these
> nutrients are doing," Byers says. "We say generalized things about
> them, calling them an antioxidant or an essential mineral, but true
> biology turns out to be more complex than that. The effects of these
> supplements are certainly not limited to the label we give them. And,
> as we've seen, sometimes the unintended effects include increased
> cancer risk."
...
> ...Byers says. "My conclusion is that taking
> high doses of any particular nutrient is more likely to be a bad
> thing than a good thing."
In plain English Byers words translate to: "We don't know, that means
it's possible."
! Many cancer cells have a high requirement for folic acid and
! overexpress the folic acid receptor. This finding has led to the
! development of anti-cancer drugs that target the folic acid
! receptor.[31]
! A meta-analysis published in 2010 failed to find a statistically
! significant cancer risk due to folic acid supplements.[32]
! Some investigations have proposed good levels of folic acid may be
! related to lower risk of esophageal, stomach, and ovarian cancers, but
! the benefits of folic acid against cancer may depend on when it is
! taken and on individual conditions. In addition, folic acid may not be
! helpful, and could even be damaging, in people already suffering from
! cancer or from a precancerous condition. Likewise, it has been
! suggested excess folate may promote tumor initiation.[33] Folate has
! shown to play a dual role in cancer development; low folate intake
! protects against early carcinogenesis, and high folate intake promotes
! advanced carcinogenesis.[34] Therefore, public health recommendations
! should be careful not to encourage too much folate intake.[34]
! Diets high in folate are associated with decreased risk of colorectal
! cancer; some studies show the association is stronger for folate from
! foods alone than for folate from foods and supplements,[35] Colorectal
! cancer is the most studied type of cancer in relation to folate and
! one carbon metabolism. One study concluded that there was not strong
! support for an association between prostate cancer risk and
! circulating concentrations of folate or vitamin B12. The researchers
! noted that while elevated concentrations of vitamin B12 may be
! associated with an increased risk for advanced stage prostate cancer,
! that this was not true of folic acid and that the association between
! B12 and cancer risk required examination in other large prospective
! studies.[36]
! Most epidemiologic studies suggest diets high in folate are associated
! with decreased risk of breast cancer, but results are not uniformly
! consistent. One broad cancer screening trial reported a potential
! harmful effect of much folate intake on breast cancer risk, suggesting
! routine folate supplementation should not be recommended as a breast
! cancer preventive,[37] but a 2007 Swedish prospective study found much
! folate intake was associated with a lower incidence of postmenopausal
! breast cancer.[38] A 2008 study has shown no significant effect of
! folic acid on overall risk of total invasive cancer or breast cancer
! among women.[39] Folate intake may not have any effect on the risk of
! breast cancer but may have an effect for women who consume at least 15
! g/d of alcohol.[40] Folate intake of more than 300 µg/d may reduce the
! risk of breast cancer in women who consume alcohol.[40]
! Most research studies associate high dietary folate intake with a
! reduced risk of prostate cancer.[36] Recently, a clinical trial showed
! daily supplementation of 1 mg of folic acid increased the risk of
! prostate cancer, while dietary and plasma folate levels among vitamin
! nonusers actually decreased the risk of prostate cancer.[41] A Finnish
! study consisting of 29,133 older male smokers observed prostate cancer
! risk had no relationship with serum folate levels.[7] [edit]
And there is no mention of cancer risk here on a government website
for users:
There are many known cancer hazards
in foods, for example nitrates used as preservatives. People who
are serious about reducing cancer risk have a lot of reading to do,
and excess vitamins is among the least of their worries.
You have a long way to go before you have half the evidence of the
link between lung cancer and cigarettes that we had in 1960. There
is much anecdotal evidence even before this. Particularly notable
was the death of King George VI from lung cancer in 1952. The
strong anecdotal evidence connecting smoking and lung cancer was the
reason that those statistical studies were funded.
It is wrong to claim that statistical studies alone prove cause and
effect. The frequent use of the comparison with tobacco is
disingenuous. In this case it is even wrong to claim that statistical
studies show the claimed linkage.
Maybe wickedpedia isn't the best reference to go by....
Not sure if this link will work for you, but it is the actual article referenced in the link posted by Gysde:
http://jnci.oxfordjournals.org/content/104/10/732.full Since you are most focused on folic acid, here's the relevant section
(RCT = randomized controlled trial, widely regarded as the gold standard):
<quote>
Folic Acid
Folate, a water soluble B-vitamin, is required for a variety of methylation-related processes. Although the terms “folate” and “folic acid” are sometimes used synonymously, the latter refers to the synthetic oxidized form that is commonly used in fortification and supplements, whereas naturally occurring folates are reduced molecules that exist in nature in several different forms with various degrees of polyglutamation. The association of folate and folic acid with cancer risk has been most intensely studied with regard to colorectal neoplasia. Although it has been proposed that synthetic sources of folate might confer greater protection than natural forms, results of one meta-analysis of observational studies of colorectal cancer showed that total folate (dietary plus synthetic sources) did not provide greater protection than dietary folate. In contrast to observational data showing a protective association of folate status with risk, a recent meta-analysis of RCTs found no effect of folic acid supplementation on risk of colorectal adenomas over the 3-year treatment period. In view of these findings, folic acid does not seem to be a promising avenue for colon cancer prevention as previously hoped.
Contrary to the hypothesized benefit, the results of one trial showed that long-term folic acid supplementation increases risk of advanced colorectal adenomas (relative risk = 1.67; 95% confidence interval = 1.00 to 2.80) and of developing three or more adenomas (relative risk = 2.32; 95% confidence interval = 1.23 to 4.35). In this RCT, increased risk of prostate cancer was also found. Because preclinical studies show the potential for a pro-neoplastic effect of folate—at least in animals with preexisting neoplasms—the possibility of enhanced carcinogenesis is a concern. Consistent with this idea, observational studies have linked higher dietary intake as well as higher circulating concentrations of folate with increased prostate cancer risk; higher risk of breast cancer has also been shown among individuals with higher folic acid intake. Whether folic acid supplementation can have adverse effects is a topic that needs further investigation. This is particularly important in countries such as the United States, where government-mandated folic acid fortification of the food supply, which began in 1996, has resulted in higher overall intake of this nutrient and use of supplements containing folic acid is widespread.
<endquote>
And the snippet below, from the conclusions, is priceless:
<quote>
Whether these trials will find benefits from supplementation for cancer prevention is unknown. In considering the current evidence, many expert committees and organizations have made public health recommendations, generally concluding that nutritional supplements have little to no benefit in preventing cancer (Table 1 [sniped]).
Given this general consensus, why do so many people in the United States continue to use dietary supplements? A large part of the answer lies in messages from supplement manufacturers, who suggest that there are health benefits, including cancer prevention, from supplements. Undoubtedly, use is driven by a common belief that supplements can improve health and protect against disease, and that at worst, they are harmless. However, the assumption that any dietary supplement is safe under all circumstances and in all quantities is no longer empirically reasonable. Believers in supplements are sometimes quick to discredit caution over supplement use, as they suggest that the tendency of mainstream science to ignore nonconventional evidence is tainted or that mainstream science is somehow corrupted by its link to a medical–industrial complex that seeks to protect profits rather than prevent disease. Results of a recent survey showed that most US supplement users report that they would continue to use supplements even if scientific evidence found them to be ineffective or if the FDA specifically deemed them ineffective. Perhaps, it is generally assumed by supplement users that these products are as well regulated as over-the-counter medications. These beliefs underscore the need for efforts by scientists and government officials to encourage the public to make prudent decisions based on sound evidence with respect to use of dietary supplements for cancer prevention.
<endquote>
> On Tue, 15 May 2012 23:35:50 +0200
> "GysdeJongh"<JonghSevenHundredElevenAtPlanet.nl> wrote:
>> Causation is no corelation. All dokters are idiots paid by big
>> pharma, so they will do anything to deprive us from cheap and
>> effective solutions. Supplements and vitamins are essential for your
>> health. The more you take the better of course.
>> Gys
>> Beta-carotene, selenium and folic acid - taken up to three times
>> their recommended daily allowance, these supplements are probably
>> harmless...
> ...
>> We have a window into less than half of the biology of what these
>> nutrients are doing," Byers says. "We say generalized things about
>> them, calling them an antioxidant or an essential mineral, but true
>> biology turns out to be more complex than that. The effects of these
>> supplements are certainly not limited to the label we give them. And,
>> as we've seen, sometimes the unintended effects include increased
>> cancer risk."
> ...
>> ...Byers says. "My conclusion is that taking
>> high doses of any particular nutrient is more likely to be a bad
>> thing than a good thing."
> In plain English Byers words translate to: "We don't know, that means
> it's possible."
> ! Many cancer cells have a high requirement for folic acid and
> ! overexpress the folic acid receptor. This finding has led to the
> ! development of anti-cancer drugs that target the folic acid
> ! receptor.[31]
> ! A meta-analysis published in 2010 failed to find a statistically
> ! significant cancer risk due to folic acid supplements.[32]
> ! Some investigations have proposed good levels of folic acid may be
> ! related to lower risk of esophageal, stomach, and ovarian cancers, but
> ! the benefits of folic acid against cancer may depend on when it is
> ! taken and on individual conditions. In addition, folic acid may not be
> ! helpful, and could even be damaging, in people already suffering from
> ! cancer or from a precancerous condition. Likewise, it has been
> ! suggested excess folate may promote tumor initiation.[33] Folate has
> ! shown to play a dual role in cancer development; low folate intake
> ! protects against early carcinogenesis, and high folate intake promotes
> ! advanced carcinogenesis.[34] Therefore, public health recommendations
> ! should be careful not to encourage too much folate intake.[34]
> ! Diets high in folate are associated with decreased risk of colorectal
> ! cancer; some studies show the association is stronger for folate from
> ! foods alone than for folate from foods and supplements,[35] Colorectal
> ! cancer is the most studied type of cancer in relation to folate and
> ! one carbon metabolism. One study concluded that there was not strong
> ! support for an association between prostate cancer risk and
> ! circulating concentrations of folate or vitamin B12. The researchers
> ! noted that while elevated concentrations of vitamin B12 may be
> ! associated with an increased risk for advanced stage prostate cancer,
> ! that this was not true of folic acid and that the association between
> ! B12 and cancer risk required examination in other large prospective
> ! studies.[36]
> ! Most epidemiologic studies suggest diets high in folate are associated
> ! with decreased risk of breast cancer, but results are not uniformly
> ! consistent. One broad cancer screening trial reported a potential
> ! harmful effect of much folate intake on breast cancer risk, suggesting
> ! routine folate supplementation should not be recommended as a breast
> ! cancer preventive,[37] but a 2007 Swedish prospective study found much
> ! folate intake was associated with a lower incidence of postmenopausal
> ! breast cancer.[38] A 2008 study has shown no significant effect of
> ! folic acid on overall risk of total invasive cancer or breast cancer
> ! among women.[39] Folate intake may not have any effect on the risk of
> ! breast cancer but may have an effect for women who consume at least 15
> ! g/d of alcohol.[40] Folate intake of more than 300 µg/d may reduce the
> ! risk of breast cancer in women who consume alcohol.[40]
> ! Most research studies associate high dietary folate intake with a
> ! reduced risk of prostate cancer.[36] Recently, a clinical trial showed
> ! daily supplementation of 1 mg of folic acid increased the risk of
> ! prostate cancer, while dietary and plasma folate levels among vitamin
> ! nonusers actually decreased the risk of prostate cancer.[41] A Finnish
> ! study consisting of 29,133 older male smokers observed prostate cancer
> ! risk had no relationship with serum folate levels.[7] [edit]
> And there is no mention of cancer risk here on a government website
> for users:
deT notsuH wrote:
> Maybe wickedpedia isn't the best reference to go by....
> Not sure if this link will work for you, but it is the actual article
> referenced in the link posted by Gysde:
> http://jnci.oxfordjournals.org/content/104/10/732.full > Since you are most focused on folic acid, here's the relevant section
> (RCT = randomized controlled trial, widely regarded as the gold
> standard): <quote>
> Folic Acid
Thank you for the extensive quote from this article deT notsuH :) It's not free to read for everyone so I welcome this contribution.
I posted a bit cynical comment on top of my post to help the usual suspects with their usual comment. Did not help of course
ra...@val.com wrote:
>> In the case of folic acid, I've taken far above normal amount of it
>> daily for the last 6 years with no adverse effects. Apparently it
>> only affects some people, if that.
> I'd really recommend a tutorial on stats and probability. The data
> don't show that Everyone that takes excess (above RDA) of folic acids
> has problems, but a significant number do.
> Many have made the same claims of smoking and health. Even me in my
> younger, smoking days. Do you think that's a valid refutation of the
> data on cigarettes.
Hi Randy,
nice to see you back posting. For a few seconds I wondered if our mutual friend <Empty> Boob </Emprty>spoiled the fun for you.
I smoked from about 6 years old. I was born in the Rotterdam Harbour area. Every body smoked. Even the cat. My grandfather smoked till he was 95. I smoked till 1996 2 packs a day. That is packs of dark tobaco to make your own (40) cigarettes.
I don't have any cancers, nor my grandfather. My sister just dies of lung cancer. She never smoked. Statistics is not for sissies.
Maya Zuiderweg wrote:
> mainframetech formuleerde de vraag :
>> On May 15, 6:29 pm, "ra...@val.com" <ra...@val.com> wrote:
>>>> In the case of folic acid, I've taken far above normal amount of it
>>>> daily for the last 6 years with no adverse effects. Apparently it
>>>> only affects some people, if that.
>>> I'd really recommend a tutorial on stats and probability. The data
>>> don't show that Everyone that takes excess (above RDA) of folic
>>> acids has problems, but a significant number do.
>>> Many have made the same claims of smoking and health. Even me in my
>>> younger, smoking days. Do you think that's a valid refutation of the
>>> data on cigarettes.
>> One of the reasons Folic Acid is added to so many things in our
>> diet is that the food processing they do on our food takes it out,
>> along with many other vitamins and nutrients. The story goes that
>> they were made to put back many of them, but it took 30 years to get
>> the FDA to insist on putting back Folic Acid. I personally doubt
>> that the food processors are putting back any more than they took
>> out to keep costs down.
>> If a 'significant number' are affected by too much Folic Acid, I
>> too would like to see the statistics on that, or even the anecdotal
>> information. You see there's a group out there that would be very
>> happy to have everyone get away from supplements and vitamins, and
>> they have enough money to cause all kinds of stories to be generated
>> and spread around.
>> As it turns out, before I quit I smoked 1.5 packs a day for about
>> 45 years with no cancer, so that's 2 people to begin new statistics.
>> When you get them compiled, let me know...:)
>> Chris
> One more: my mother smoked 2 packs of cigarettes a day for over 70
> years. No cancer.
Cancer is a Bingo in Molecular Biology. Loosely speaking : you only can collect your price is you have 10 numbers on a row right. Even 9 numbers on a row right won't do.
Your mother smoked 2 packs / day for over 70 years and won nothing. She did not manage to get 10 right numbers on a row. You don't know if she had 9 numbers and died just before the tenth.
My grandmother bought a ticket in the State Lottery for about 30 years and never ver won anything. That gave her the right to get a ticket for free for the rest of her life.
She (of course) won nothing with those free tickets either. She used to say : "Hey I'm lucky in love, you can't have it all"
What does it prove ? Does it prove that no one will ever win the States Lotery ? That no one will ever win any Bingo ? That no one will ever get cancer ?
Gys Quoted:
" ...Byers says. "My conclusion is that taking
high doses of any particular nutrient is more likely to be a bad
thing than a good thing."
Trawley responded:
> In plain English Byers words translate to: "We don't know, that means
> it's possible."
That's sure not a "plain English" translation to my mind, especially
when considering the references.
The fact that, animal studies, where extraneous variables can be
tightly controlled, show the similar results is very damning in my
view.
[1] . T
Also the human studies include not only "obeservation data, but case
controlled data is not something to easily scuff at. I love Wikipedia,
but its a starting off point for research - not the final word. {2]
[3]
These references is by no means exhaustive.
1.
Role of Folate in Colon Cancer Development and Progression1
Young-In Kim2
+ Author Affiliations
Departments of Medicine and Nutritional Sciences, University of
Toronto, Toronto, Ontario, Canada and Division of Gastroenterology,
St. Michael's Hospital, Toronto, Ontario, Canada
↵2To whom correspondence should be addressed. E-mail:
youngin....@utoronto.ca.
Abstract
Folate, a water-soluble B vitamin and important cofactor in 1-carbon
transfer, is an important nutritional factor that may modulate the
development of colorectal cancer. Epidemiologic and clinical studies
indicate that dietary folate intake and blood folate levels are
inversely associated with colorectal cancer risk. Collectively, these
studies suggest an ∼40% reduction in the risk of colorectal cancer in
individuals with the highest dietary folate intake compared with those
with the lowest intake. Animal studies using chemical and genetically
predisposed rodent models have provided considerable support for a
causal relationship between folate depletion and colorectal
carcinogenesis as well as a dose-dependent protective effect of folate
supplementation. However, animal studies have also shown that the dose
and timing of folate intervention are critical in providing safe and
effective chemoprevention; exceptionally high supplemental folate
levels and folate intervention after microscopic neoplastic foci are
established in the colorectal mucosa promote rather than suppress
colorectal carcinogenesis. These animal studies in conjunction with
clinical observations suggest that folate possesses the dual
modulatory effects on carcinogenesis depending on the timing and dose
of folate intervention. Folate deficiency has an inhibitory effect
whereas folate supplementation has a promoting effect on progression
of established neoplasms. In contrast, folate deficiency in normal
epithelial tissues appears to predispose them to neoplastic
transformation, and modest levels of folate supplementation suppress
the development of tumors in normal tissues. Notwithstanding the
limitations associated with animal models, these animal studies
suggest that the optimal timing and dose of folate intervention need
to be established for safe and effective chemoprevention in humans.
2.
Folate, cancer risk, and the Greek god, Proteus: a tale of two
chameleons.
Mason JB.
Source
USDA Human Nutrition Research Center on Aging at Tufts University,
Boston, Massachusetts 02111, USA. joel.ma...@tufts.edu
Abstract
Evidence indicates that an abundant intake of foodstuffs rich in
folate conveys protection against the development of colorectal
cancer, and perhaps some other common cancers as well. The issue is
complex, however, since some observations in animal and human studies
demonstrate that an overly abundant intake of folate among those who
harbor existing foci of neoplasia might instead produce a paradoxical
promotion of tumorigenesis. The pharmaceutical form of the vitamin,
folic acid, might affect the process in a manner that is distinct from
natural forms of the vitamin, although this remains a speculative
concept. Our limited understanding of this complex relationship is
impeding efforts to move ahead with widespread folic acid
fortification, but this delay may be necessary to ensure that such
programs are instituted in a safe manner.
3.
Circulating folate, vitamin B12, homocysteine, vitamin B12 transport
proteins, and risk of prostate cancer: a case-control study,
systematic review, and meta-analysis.
Collin SM, Metcalfe C, Refsum H, Lewis SJ, Zuccolo L, Smith GD, Chen
L, Harris R, Davis M, Marsden G, Johnston C, Lane JA, Ebbing M, Bønaa
KH, Nygård O, Ueland PM, Grau MV, Baron JA, Donovan JL, Neal DE, Hamdy
FC, Smith AD, Martin RM.
Source
Department of Social Medicine, University of Bristol, Bristol, United
Kingdom. simon.col...@bristol.ac.uk
Abstract
BACKGROUND:
Disturbed folate metabolism is associated with an increased risk of
some cancers. Our objective was to determine whether blood levels of
folate, vitamin B(12), and related metabolites were associated with
prostate cancer risk.
METHODS:
Matched case-control study nested within the U.K. population-based
Prostate testing for cancer and Treatment (ProtecT) study of prostate-
specific antigen-detected prostate cancer in men ages 50 to 69 years.
Plasma concentrations of folate, B(12) (cobalamin), holo-haptocorrin,
holo-transcobalamin total transcobalamin, and total homocysteine
(tHcy) were measured in 1,461 cases and 1,507 controls. ProtecT study
estimates for associations of folate, B(12), and tHcy with prostate
cancer risk were included in a meta-analysis, based on a systematic
review.
RESULTS:
In the ProtecT study, increased B(12) and holo-haptocorrin
concentrations showed positive associations with prostate cancer risk
[highest versus lowest quartile of B(12) odds ratio (OR) = 1.17 (95%
confidence interval, 0.95-1.43); P(trend) = 0.06; highest versus
lowest quartile of holo-haptocorrin OR = 1.27 (1.04-1.56); P(trend) =
0.01]; folate, holo-transcobalamin, and tHcy were not associated with
prostate cancer risk. In the meta-analysis, circulating B(12) levels
were associated with an increased prostate cancer risk [pooled OR =
1.10 (1.01-1.19) per 100 pmol/L increase in B(12); P = 0.002]; the
pooled OR for the association of folate with prostate cancer was
positive [OR = 1.11 (0.96-1.28) per 10 nmol/L; P = 0.2) and
conventionally statistically significant if ProtecT (the only case-
control study) was excluded [OR = 1.18 (1.00-1.40) per 10 nmol/L; P =
0.02].
CONCLUSION:
Vitamin B(12) and (in cohort studies) folate were associated with
increased prostate cancer risk.
> ! Many cancer cells have a high requirement for folic acid and
> ! overexpress the folic acid receptor. This finding has led to the
> ! development of anti-cancer drugs that target the folic acid
> ! receptor.[31]
> ! A meta-analysis published in 2010 failed to find a statistically
> ! significant cancer risk due to folic acid supplements.[32]
> ! Some investigations have proposed good levels of folic acid may be
> ! related to lower risk of esophageal, stomach, and ovarian cancers, but
> ! the benefits of folic acid against cancer may depend on when it is
> ! taken and on individual conditions. In addition, folic acid may not be
> ! helpful, and could even be damaging, in people already suffering from
> ! cancer or from a precancerous condition. Likewise, it has been
> ! suggested excess folate may promote tumor initiation.[33] Folate has
> ! shown to play a dual role in cancer development; low folate intake
> ! protects against early carcinogenesis, and high folate intake promotes
> ! advanced carcinogenesis.[34] Therefore, public health recommendations
> ! should be careful not to encourage too much folate intake.[34]
> ! Diets high in folate are associated with decreased risk of colorectal
> ! cancer; some studies show the association is stronger for folate from
> ! foods alone than for folate from foods and supplements,[35] Colorectal
> ! cancer is the most studied type of cancer in relation to folate and
> ! one carbon metabolism. One study concluded that there was not strong
> ! support for an association between prostate cancer risk and
> ! circulating concentrations of folate or vitamin B12. The researchers
> ! noted that while elevated concentrations of vitamin B12 may be
> ! associated with an increased risk for advanced stage prostate cancer,
> ! that this was not true of folic acid and that the association between
> ! B12 and cancer risk required examination in other large prospective
> ! studies.[36]
> ! Most epidemiologic studies suggest diets high in folate are associated
> ! with decreased risk of breast cancer, but results are not uniformly
> ! consistent. One broad cancer screening trial reported a potential
> ! harmful effect of much folate intake on breast cancer risk, suggesting
> ! routine folate supplementation should not be recommended as a breast
> ! cancer preventive,[37] but a 2007 Swedish prospective study found much
> ! folate intake was associated with a lower incidence of postmenopausal
> ! breast cancer.[38] A 2008 study has shown no significant effect of
> ! folic acid on overall risk of total invasive cancer or breast cancer
> ! among women.[39] Folate intake may not have any effect on the risk of
> ! breast cancer but may have an effect for women who consume at least 15
> ! g/d of alcohol.[40] Folate intake of more than 300 µg/d may reduce the
> ! risk of breast cancer in women who consume alcohol.[40]
> ! Most research studies associate high dietary folate intake with a
> ! reduced risk of prostate cancer.[36] Recently, a clinical trial showed
> ! daily supplementation of 1 mg of folic acid increased the risk of
> ! prostate cancer, while dietary and plasma folate
On May 16, 9:33 am, "ra...@val.com" <ra...@val.com> wrote:
> mainframetech wrote:
> > I personally doubt that the food
> > processors are putting back any more than they took out to keep costs
> > down.
> reply:
> They are putting a Lot (a whole lot in many cases >300%) more in than
> they take out. Some boxed cereals add the full RDA amount in one
> serving.
That doesn't make sense. For every box of cereal they remove a
certain amount, which is spread over the many bowls in each box. Why
would they put back in more per bowl than they took out? Not good
sense for a corporation to spend more than necessary. I can see them
putting in a bit more than they're supposed to just to be sure they
meet their obligation, but not much more than that.
> mainframe tech wrote:
> "If a 'significant number' are affected by too much Folic Acid, I
> too would like to see the statistics on that, or even the anecdotal
> information."
> One review estimated 15.000 additional cancers due to excess folic
> acid intake from 1996 - 2000!
> Here's some more references:
> Cole BF, Baron JA, Sandler RS, et al. Folic acid for the prevention of
> colorectal adenomas: a randomized clinical trial. JAMA. 2007;297(21):
> 2351–2359.
> Figueiredo JC, Grau MV, Haile RW, et al. Folic acid and risk of
> prostate cancer: results from a randomized clinical trial. J Natl
> Cancer Inst. 2009;101(6):432–435.
> Kim YI. Role of folate in colon cancer development and progression. J
> Nutr. 2003;133(11)(suppl 1):3731S–3739S.
> Mason JB. Folate, cancer risk, and the Greek god, Proteus: a tale of
> two chameleons. Nutr Rev. 2009;67(4):206–212.
> Collin SM, Metcalfe C, Refsum H, et al. Circulating folate, vitamin
> B12, homocysteine, vitamin B12 transport proteins, and risk of
> prostate cancer: a case-control study, systematic review, and meta-
> analysis. Cancer Epidemiol Biomarkers Prev. 2010;19(6):1632–1642.
> Lawson KA, Wright ME, Subar A, et al. Multivitamin use and risk of
> prostate cancer in the National Institutes of Health-AARP Diet and
> Health Study. J Natl Cancer Inst. 2007;99(10):754–764.
> Stolzenberg-Solomon RZ, Chang SC, Leitzmann MF, et al. Folate intake,
> alcohol use, and postmenopausal breast cancer risk in the Prostate,
> Lung, Colorectal, and Ovarian Cancer Screening Trial. Am J Clin Nutr.
> 2006;83(4):895–904.
> Randy
Sorry. I mentioned that I'd like to see the statistics or anecdotal
information, but I forgot to mention that I had no intention of doing
the research, or looking up a bunch of studies for you. I thought you
had come across some statistics somewhere or some comprehensive
anecdotal information. And I would have liked to see it.
As noted, I still take a much larger amount of folic acid than the
RDA with no obvious negative effects. That's a count of one in the
statistics if you're going to compile them. Add me in.
You see, I've looked at Folic Acid off and on for many years and
haven't seen talk of cancer until the last few years. For the way I
look at things, I'm a bit leery of something new of this type that
would be suchj a godsend to the drug industry. They would be very
happy that folic acid caused cancer, and if you'll think about it,
there have been a number of articles about exactly that, but talking
of many other supplements and vitamins. Some of which have been taken
in large doses by many for many years, such as C and D.
I'll keep an eye out for some statistics and who presents them and
see what comes of it...Thanks..:)
> "GysdeJongh" <JonghSevenHundredElevenAtPlanet.nl> wrote:
> > Causation is no corelation. All dokters are idiots paid by big
> > pharma, so they will do anything to deprive us from cheap and
> > effective solutions. Supplements and vitamins are essential for your
> > health. The more you take the better of course.
> > Gys
> > Beta-carotene, selenium and folic acid - taken up to three times
> > their recommended daily allowance, these supplements are probably
> > harmless...
> ...
> > We have a window into less than half of the biology of what these
> > nutrients are doing," Byers says. "We say generalized things about
> > them, calling them an antioxidant or an essential mineral, but true
> > biology turns out to be more complex than that. The effects of these
> > supplements are certainly not limited to the label we give them. And,
> > as we've seen, sometimes the unintended effects include increased
> > cancer risk."
> ...
> > ...Byers says. "My conclusion is that taking
> > high doses of any particular nutrient is more likely to be a bad
> > thing than a good thing."
> In plain English Byers words translate to: "We don't know, that means
> it's possible."
> ! Many cancer cells have a high requirement for folic acid and
> ! overexpress the folic acid receptor. This finding has led to the
> ! development of anti-cancer drugs that target the folic acid
> ! receptor.[31]
> ! A meta-analysis published in 2010 failed to find a statistically
> ! significant cancer risk due to folic acid supplements.[32]
> ! Some investigations have proposed good levels of folic acid may be
> ! related to lower risk of esophageal, stomach, and ovarian cancers, but
> ! the benefits of folic acid against cancer may depend on when it is
> ! taken and on individual conditions. In addition, folic acid may not be
> ! helpful, and could even be damaging, in people already suffering from
> ! cancer or from a precancerous condition. Likewise, it has been
> ! suggested excess folate may promote tumor initiation.[33] Folate has
> ! shown to play a dual role in cancer development; low folate intake
> ! protects against early carcinogenesis, and high folate intake promotes
> ! advanced carcinogenesis.[34] Therefore, public health recommendations
> ! should be careful not to encourage too much folate intake.[34]
> ! Diets high in folate are associated with decreased risk of colorectal
> ! cancer; some studies show the association is stronger for folate from
> ! foods alone than for folate from foods and supplements,[35] Colorectal
> ! cancer is the most studied type of cancer in relation to folate and
> ! one carbon metabolism. One study concluded that there was not strong
> ! support for an association between prostate cancer risk and
> ! circulating concentrations of folate or vitamin B12. The researchers
> ! noted that while elevated concentrations of vitamin B12 may be
> ! associated with an increased risk for advanced stage prostate cancer,
> ! that this was not true of folic acid and that the association between
> ! B12 and cancer risk required examination in other large prospective
> ! studies.[36]
> ! Most epidemiologic studies suggest diets high in folate are associated
> ! with decreased risk of breast cancer, but results are not uniformly
> ! consistent. One broad cancer screening trial reported a potential
> ! harmful effect of much folate intake on breast cancer risk, suggesting
> ! routine folate supplementation should not be recommended as a breast
> ! cancer preventive,[37] but a 2007 Swedish prospective study found much
> ! folate intake was associated with a lower incidence of postmenopausal
> ! breast cancer.[38] A 2008 study has shown no significant effect of
> ! folic acid on overall risk of total invasive cancer or breast cancer
> ! among women.[39] Folate intake may not have any effect on the risk of
> ! breast cancer but may have an effect for women who consume at least 15
> ! g/d of alcohol.[40] Folate intake of more than 300 µg/d may reduce the
> ! risk of breast cancer in women who consume alcohol.[40]
> ! Most research studies associate high dietary folate intake with a
> ! reduced risk of prostate cancer.[36] Recently, a clinical trial showed
> ! daily supplementation of 1 mg of folic acid increased the risk of
> ! prostate cancer, while dietary and plasma folate levels among vitamin
> ! nonusers actually decreased the risk of prostate cancer.[41] A Finnish
> ! study consisting of 29,133 older male smokers observed prostate cancer
> ! risk had no relationship with serum folate levels.[7] [edit]
> And there is no mention of cancer risk here on a government website
> for users:
> There are many known cancer hazards
> in foods, for example nitrates used as preservatives. People who
> are serious about reducing cancer risk have a lot of reading to do,
> and excess vitamins is among the least of their worries.
> You have a long way to go before you have half the evidence of the
> link between lung cancer and cigarettes that we had in 1960. There
> is much anecdotal evidence even before this. Particularly notable
> was the death of King George VI from lung cancer in 1952. The
> strong anecdotal evidence connecting smoking and lung cancer was the
> reason that those statistical studies were funded.
> It is wrong to claim that statistical studies alone prove cause and
> effect. The frequent use of the comparison with tobacco is
> disingenuous. In this case it is even wrong to claim that statistical
> studies show the claimed linkage.
You raise an important point that the supplement or vitamin in
question or the person in question can both have many other factors
that may bear on any particular point. The complexity of the human
organism makes any quest much more involved than we can know yet.
Even a particular compound may have elements beyond what we know of
it. It's a lot like just accepting GMO foods because someone said
they're exactly like the normal foods. In the case of DNA, the
differences and cross reliances are too many to fathom, and many are
not yet known and still being discovered daily.
> Maybe wickedpedia isn't the best reference to go by....
> Not sure if this link will work for you, but it is the actual article
> referenced in the link posted by Gysde:http://jnci.oxfordjournals.org/content/104/10/732.full > Since you are most focused on folic acid, here's the relevant section
> (RCT = randomized controlled trial, widely regarded as the gold standard):
> <quote>
> Folic Acid
> Folate, a water soluble B-vitamin, is required for a variety of
> methylation-related processes. Although the terms “folate” and “folic
> acid” are sometimes used synonymously, the latter refers to the
> synthetic oxidized form that is commonly used in fortification and
> supplements, whereas naturally occurring folates are reduced molecules
> that exist in nature in several different forms with various degrees of
> polyglutamation. The association of folate and folic acid with cancer
> risk has been most intensely studied with regard to colorectal
> neoplasia. Although it has been proposed that synthetic sources of
> folate might confer greater protection than natural forms, results of
> one meta-analysis of observational studies of colorectal cancer showed
> that total folate (dietary plus synthetic sources) did not provide
> greater protection than dietary folate. In contrast to observational
> data showing a protective association of folate status with risk, a
> recent meta-analysis of RCTs found no effect of folic acid
> supplementation on risk of colorectal adenomas over the 3-year treatment
> period. In view of these findings, folic acid does not seem to be a
> promising avenue for colon cancer prevention as previously hoped.
> Contrary to the hypothesized benefit, the results of one trial showed
> that long-term folic acid supplementation increases risk of advanced
> colorectal adenomas (relative risk = 1.67; 95% confidence interval =
> 1.00 to 2.80) and of developing three or more adenomas (relative risk =
> 2.32; 95% confidence interval = 1.23 to 4.35). In this RCT, increased
> risk of prostate cancer was also found. Because preclinical studies show
> the potential for a pro-neoplastic effect of folate—at least in animals
> with preexisting neoplasms—the possibility of enhanced carcinogenesis is
> a concern. Consistent with this idea, observational studies have linked
> higher dietary intake as well as higher circulating concentrations of
> folate with increased prostate cancer risk; higher risk of breast cancer
> has also been shown among individuals with higher folic acid intake.
> Whether folic acid supplementation can have adverse effects is a topic
> that needs further investigation. This is particularly important in
> countries such as the United States, where government-mandated folic
> acid fortification of the food supply, which began in 1996, has resulted
> in higher overall intake of this nutrient and use of supplements
> containing folic acid is widespread.
> <endquote>
> And the snippet below, from the conclusions, is priceless:
> <quote>
> Whether these trials will find benefits from supplementation for cancer
> prevention is unknown. In considering the current evidence, many expert
> committees and organizations have made public health recommendations,
> generally concluding that nutritional supplements have little to no
> benefit in preventing cancer (Table 1 [sniped]).
> Given this general consensus, why do so many people in the United States
> continue to use dietary supplements? A large part of the answer lies in
> messages from supplement manufacturers, who suggest that there are
> health benefits, including cancer prevention, from supplements.
> Undoubtedly, use is driven by a common belief that supplements can
> improve health and protect against disease, and that at worst, they are
> harmless. However, the assumption that any dietary supplement is safe
> under all circumstances and in all quantities is no longer empirically
> reasonable. Believers in supplements are sometimes quick to discredit
> caution over supplement use, as they suggest that the tendency of
> mainstream science to ignore nonconventional evidence is tainted or that
> mainstream science is somehow corrupted by its link to a
> medical–industrial complex that seeks to protect profits rather than
> prevent disease. Results of a recent survey showed that most US
> supplement users report that they would continue to use supplements even
> if scientific evidence found them to be ineffective or if the FDA
> specifically deemed them ineffective. Perhaps, it is generally assumed
> by supplement users that these products are as well regulated as
> over-the-counter medications. These beliefs underscore the need for
> efforts by scientists and government officials to encourage the public
> to make prudent decisions based on sound evidence with respect to use of
> dietary supplements for cancer prevention.
> <endquote>
> On 5/16/2012 3:07 PM, Trawley Trash wrote:> On Tue, 15 May 2012 23:35:50 +0200
> > "GysdeJongh"<JonghSevenHundredElevenAtPlanet.nl> wrote:
> >> Causation is no corelation. All dokters are idiots paid by big
> >> pharma, so they will do anything to deprive us from cheap and
> >> effective solutions. Supplements and vitamins are essential for your
> >> health. The more you take the better of course.
> >> Gys
> >> Beta-carotene, selenium and folic acid - taken up to three times
> >> their recommended daily allowance, these supplements are probably
> >> harmless...
> > ...
> >> We have a window into less than half of the biology of what these
> >> nutrients are doing," Byers says. "We say generalized things about
> >> them, calling them an antioxidant or an essential mineral, but true
> >> biology turns out to be more complex than that. The effects of these
> >> supplements are certainly not limited to the label we give them. And,
> >> as we've seen, sometimes the unintended effects include increased
> >> cancer risk."
> > ...
> >> ...Byers says. "My conclusion is that taking
> >> high doses of any particular nutrient is more likely to be a bad
> >> thing than a good thing."
> > In plain English Byers words translate to: "We don't know, that means
> > it's possible."
> > ! Many cancer cells have a high requirement for folic acid and
> > ! overexpress the folic acid receptor. This finding has led to the
> > ! development of anti-cancer drugs that target the folic acid
> > ! receptor.[31]
> > ! A meta-analysis published in 2010 failed to find a statistically
> > ! significant cancer risk due to folic acid supplements.[32]
> > ! Some investigations have proposed good levels of folic acid may be
> > ! related to lower risk of esophageal, stomach, and ovarian cancers, but
> > ! the benefits of folic acid against cancer may depend on when it is
> > ! taken and on individual conditions. In addition, folic acid may not be
> > ! helpful, and could even be damaging, in people already suffering from
> > ! cancer or from a precancerous condition. Likewise, it has been
> > ! suggested excess folate may promote tumor initiation.[33] Folate has
> > ! shown to play a dual role in cancer development; low folate intake
> > ! protects against early carcinogenesis, and high folate intake promotes
> > ! advanced carcinogenesis.[34] Therefore, public health recommendations
> > ! should be careful not to encourage too much folate intake.[34]
> > ! Diets high in folate are associated with decreased risk of colorectal
> > ! cancer; some studies show the association is stronger for folate from
> > ! foods alone than for folate from foods and supplements,[35] Colorectal
> > ! cancer is the most studied type of cancer in relation to folate and
> > ! one carbon metabolism. One study concluded that there was not strong
> > ! support for an association between prostate cancer risk and
> > ! circulating concentrations of folate or vitamin B12. The researchers
> > ! noted that while elevated concentrations of vitamin B12 may be
> > ! associated with an increased risk for advanced stage prostate cancer,
> > ! that this was not true of folic acid and that the association between
> > ! B12 and cancer risk required examination in other large prospective
> > ! studies.[36]
> > ! Most epidemiologic studies suggest diets high in folate are associated
> > ! with decreased risk of breast cancer, but results are not uniformly
> > ! consistent. One broad cancer screening trial reported a potential
> > ! harmful effect of much folate intake on breast cancer risk, suggesting
> > ! routine folate supplementation should not be recommended as a breast
> > ! cancer preventive,[37] but a 2007 Swedish prospective study found much
> > ! folate intake was associated with a lower incidence of postmenopausal
> > ! breast cancer.[38] A 2008 study has shown no significant effect of
> > ! folic acid on overall risk of total invasive cancer or breast cancer
> > ! among women.[39] Folate intake may not have any effect on the risk of
> > ! breast cancer but may have an effect for women who consume at least 15
> > ! g/d of alcohol.[40] Folate intake of more than 300 µg/d may reduce the
> > ! risk of breast cancer in women who consume alcohol.[40]
> > ! Most research studies associate high dietary folate intake with a
> > ! reduced risk of prostate cancer.[36] Recently, a clinical trial showed
> > ! daily supplementation of 1 mg of folic acid increased the risk of
> > ! prostate cancer, while dietary and plasma folate levels among vitamin
> > !
"ra...@val.com" <ra...@val.com> wrote:
> Trawley responded:
> > In plain English Byers words translate to: "We don't know, that
> > means it's possible."
> That's sure not a "plain English" translation to my mind, especially
> when considering the references.
No relevant references in the link Gys posted. Did you read the same text
that I did?
> The fact that, animal studies, where extraneous variables can be
> tightly controlled, show the similar results is very damning in my
> view.
> [1] . T
Wikipedida quoted a 2010 study that found no correlation.
Furthermore I have the following objections:
1) Supplements causing cancer has nothing to do with diabetes.
You are spamming here for some hidden agenda.
2) It is not correct to say that a few studies involving folate
justify the statement that "Dietary supplements cause cancer."
If folate does cause cancer, then do post about it in an
appropriate venue, or correct wikipedia.
3) There are many other reasons for supplements than curing
cancer. The positive benefits must be weighted against
the risks.
These positive benefits are individual in nature. We
each have a unique biochemistry, and the benefit is something
we each have to decide for ourselves.
deT notsuH <pcird*BACKWAR...@umich.edu> wrote:
> Maybe wickedpedia isn't the best reference to go by....
Agreed, but you didn't even look it up. Other studies
referenced in the Wikepedia article showed no statistically
significant correlation. You have no comment on these.
You have no comment on the wikipedia article, just another
reference that we cannot read. According to the quoted text
there is only 95 percent confidence in the result. That is
not enough to override other contradicting studies.
> Since you are most focused on folic acid, here's the relevant section
> (RCT = randomized controlled trial, widely regarded as the gold
> standard): <quote>
No, I am not focused on folic acid. Gys brought the subject up.
I do not like to see a shakey study result on one supplement used to
back of the overly broad generalization that "Dietary Supplements
increase cancer risk." This implies that other supplements that
were not studied also cause cancer. That is wrong.
The original link posted does not even sufficiently back up the
assertion that folic acid is linked to cancer.
Even if folic acid is linked to
cancer, that does not show that folic acid *causes* cancer. For
one thing the most common use of the supplement is by pregnant women.
Pregnant women are more likely to have health problems.
Then there is the presumed benefit of taking folic acid in preventing
health problems in the developing fetus. You need much more
convincing data than has been shown so far to say pregnant women
should not take this supplement.
The references quoted are not suffient make the point.
> Maya Zuiderweg wrote:
>> mainframetech formuleerde de vraag :
>>> On May 15, 6:29 pm, "ra...@val.com" <ra...@val.com> wrote:
>>>>> In the case of folic acid, I've taken far above normal amount of it
>>>>> daily for the last 6 years with no adverse effects. Apparently it
>>>>> only affects some people, if that.
>>>> I'd really recommend a tutorial on stats and probability. The data
>>>> don't show that Everyone that takes excess (above RDA) of folic
>>>> acids has problems, but a significant number do.
>>>> Many have made the same claims of smoking and health. Even me in my
>>>> younger, smoking days. Do you think that's a valid refutation of the
>>>> data on cigarettes.
>>> One of the reasons Folic Acid is added to so many things in our
>>> diet is that the food processing they do on our food takes it out,
>>> along with many other vitamins and nutrients. The story goes that
>>> they were made to put back many of them, but it took 30 years to get
>>> the FDA to insist on putting back Folic Acid. I personally doubt
>>> that the food processors are putting back any more than they took
>>> out to keep costs down.
>>> If a 'significant number' are affected by too much Folic Acid, I
>>> too would like to see the statistics on that, or even the anecdotal
>>> information. You see there's a group out there that would be very
>>> happy to have everyone get away from supplements and vitamins, and
>>> they have enough money to cause all kinds of stories to be generated
>>> and spread around.
>>> As it turns out, before I quit I smoked 1.5 packs a day for about
>>> 45 years with no cancer, so that's 2 people to begin new statistics.
>>> When you get them compiled, let me know...:)
>>> Chris
>> One more: my mother smoked 2 packs of cigarettes a day for over 70
>> years. No cancer.
> Cancer is a Bingo in Molecular Biology. Loosely speaking : you only can > collect your price is you have 10 numbers on a row right. Even 9 numbers on a > row right won't do.
> Your mother smoked 2 packs / day for over 70 years and won nothing. She did > not manage to get 10 right numbers on a row. You don't know if she had 9 > numbers and died just before the tenth.
> My grandmother bought a ticket in the State Lottery for about 30 years and > never ver won anything. That gave her the right to get a ticket for free for > the rest of her life.
> She (of course) won nothing with those free tickets either. She used to say
> : "Hey I'm lucky in love, you can't have it all"
> What does it prove ? Does it prove that no one will ever win the States > Lotery ? That no one will ever win any Bingo ? That no one will ever get > cancer ?
> Gys
I did not say it proved anything.
Just added one more for Chris :-)
Ah, the Staatsloterij (State Lottery). Husband-of-now bought his first lottery ticket when a student, won directly a quite big sum of money (for a student it was at that time), was hooked forever, still buys them, never wins anymore.
Does that prove anything?
M.
> ra...@val.com wrote:
>>> In the case of folic acid, I've taken far above normal amount of it
>>> daily for the last 6 years with no adverse effects. Apparently it
>>> only affects some people, if that.
>> I'd really recommend a tutorial on stats and probability. The data
>> don't show that Everyone that takes excess (above RDA) of folic acids
>> has problems, but a significant number do.
>> Many have made the same claims of smoking and health. Even me in my
>> younger, smoking days. Do you think that's a valid refutation of the
>> data on cigarettes.
> Hi Randy,
> nice to see you back posting. For a few seconds I wondered if our mutual > friend <Empty> Boob </Emprty>spoiled the fun for you.
> I smoked from about 6 years old. I was born in the Rotterdam Harbour area. > Every body smoked. Even the cat. My grandfather smoked till he was 95. I > smoked till 1996 2 packs a day. That is packs of dark tobaco to make your own > (40) cigarettes.
> I don't have any cancers, nor my grandfather. My sister just dies of lung > cancer. She never smoked. Statistics is not for sissies.
"They [food manufacturers] are putting a Lot (a whole lot in many
cases >300%) more in than
they take out. Some boxed cereals add the full RDA amount in one
serving."
mainframetech wrote
"That doesn't make sense. For every box of cereal they remove a
certain amount, which is spread over the many bowls in each box.
Why
would they put back in more per bowl than they took out? Not good
sense for a corporation to spend more than necessary."
Reply:
Because in 1998 the US government Required it!!
Its was voluntary in 1996 and mandatory in 1998 that folic acid be
added to enriched grain products.
Other B vitamins have been added for over 50 years.
Next time you at the grocery store read the nutrition label on cereal
boxes. Many contain between 25 - 100 percent of the RDA of folic acid.
Combined with a good diet and supplement it's easy to get a mega dose
- the same dosages that animal and humans studies have found
problematic.
Most common box cereal products have the equivalent of a "one a day"
Wallgreen's multiple per serving.
Read the ingredients - supplemental vitamins are added. Without the
artificial supplementation, a single serving of even whole grain
cereals wouldn't have anything near the amounts of folic acid or other
vitamins.
mainframetech wrote:
> Sorry. I mentioned that I'd like to see the statistics or anecdotal
> information, but I forgot to mention that I had no intention of doing
> the research, or looking up a bunch of studies for you. I thought you
> had come across some statistics somewhere or some comprehensive
> anecdotal information. And I would have liked to see it.
What a gigantic load of crap! I provide studies, but its too much for
you look them up on google. And you call that doing research for me??
Not only do I provide the studies, but I'm required to "cut and paste"
the information from the studies so you don't have to do any work what
so ever.
Ok here some numbers for you:
1.
A random controlled placebo trial (not an observational study) got
these results:
A 67% increase in Advanced Colorectal Adenomas in the group taking the
folic acid supplement compared to placebo.
A 132% increase of developing 3 or more adenomas in the group taking
folic acid. [a][b]
2.
Last year, health officials in Chile reported that hospitalization
rates for colon cancer among men and women age 45 and older more than
doubled in their country since fortification was introduced in 2000.
[c]
3.
In 2007, Joel Mason, MD, director of the Vitamins and Carcinogenesis
Laboratory at the Tufts University School of Medicine, described a
study of the United States and Canada suggesting that rates of colon
cancer rose — following years of steady decline — in the late 1990s
(around the time our food was being fortified).
Better screening or an aging population could not explain the
difference, which amounts to an additional 15,000 cases of cancer per
year in the United States alone between 1996 and 2000, according to
Mason's calculations. "It's a critical enough issue that it can't be
ignored," he says. [c]
4.
In one study conducted in Norway, which doesn't fortify foods,
supplementation with 800 mcg of folic acid (plus B12 and B6) daily for
more than 3 years raised the risk of developing lung cancer by 21
percent. [c]
Another, in which men took either folic acid or a placebo, showed
those consuming 1,000 mcg of folic acid daily had more than twice the
risk of prostate cancer. [c]
Refs:
a:
Cole BF, Baron JA, Sandler RS, et al. Folic acid for the prevention of
colorectal adenomas: a randomized clinical trial. JAMA. 2007;297(21):
2351–2359.
On Wednesday, May 16, 2012 2:15:16 PM UTC-7, ra...@val.com wrote:
> Gys Quoted:
> " ...Byers says. "My conclusion is that taking
> high doses of any particular nutrient is more likely to be a bad
> thing than a good thing."
> Trawley responded:
> > In plain English Byers words translate to: "We don't know, that means
> > it's possible."
> That's sure not a "plain English" translation to my mind, especially
> when considering the references.
> The fact that, animal studies, where extraneous variables can be
> tightly controlled, show the similar results is very damning in my
> view.
> [1] . T
> Also the human studies include not only "obeservation data, but case
> controlled data is not something to easily scuff at. I love Wikipedia,
> but its a starting off point for research - not the final word. {2]
> [3]
> These references is by no means exhaustive.
> 1.
> Role of Folate in Colon Cancer Development and Progression1
> Young-In Kim2
> + Author Affiliations
> Departments of Medicine and Nutritional Sciences, University of
> Toronto, Toronto, Ontario, Canada and Division of Gastroenterology,
> St. Michael's Hospital, Toronto, Ontario, Canada
> ↵2To whom correspondence should be addressed. E-mail:
> youngin....@utoronto.ca.
> Abstract
> Folate, a water-soluble B vitamin and important cofactor in 1-carbon
> transfer, is an important nutritional factor that may modulate the
> development of colorectal cancer. Epidemiologic and clinical studies
> indicate that dietary folate intake and blood folate levels are
> inversely associated with colorectal cancer risk. Collectively, these
> studies suggest an ∼40% reduction in the risk of colorectal cancer in
> individuals with the highest dietary folate intake compared with those
> with the lowest intake. Animal studies using chemical and genetically
> predisposed rodent models have provided considerable support for a
> causal relationship between folate depletion and colorectal
> carcinogenesis as well as a dose-dependent protective effect of folate
> supplementation. However, animal studies have also shown that the dose
> and timing of folate intervention are critical in providing safe and
> effective chemoprevention; exceptionally high supplemental folate
> levels and folate intervention after microscopic neoplastic foci are
> established in the colorectal mucosa promote rather than suppress
> colorectal carcinogenesis. These animal studies in conjunction with
> clinical observations suggest that folate possesses the dual
> modulatory effects on carcinogenesis depending on the timing and dose
> of folate intervention. Folate deficiency has an inhibitory effect
> whereas folate supplementation has a promoting effect on progression
> of established neoplasms. In contrast, folate deficiency in normal
> epithelial tissues appears to predispose them to neoplastic
> transformation, and modest levels of folate supplementation suppress
> the development of tumors in normal tissues. Notwithstanding the
> limitations associated with animal models, these animal studies
> suggest that the optimal timing and dose of folate intervention need
> to be established for safe and effective chemoprevention in humans.
> 2.
> Folate, cancer risk, and the Greek god, Proteus: a tale of two
> chameleons.
> Mason JB.
> Source
> USDA Human Nutrition Research Center on Aging at Tufts University,
> Boston, Massachusetts 02111, USA. joel.ma...@tufts.edu
> Abstract
> Evidence indicates that an abundant intake of foodstuffs rich in
> folate conveys protection against the development of colorectal
> cancer, and perhaps some other common cancers as well. The issue is
> complex, however, since some observations in animal and human studies
> demonstrate that an overly abundant intake of folate among those who
> harbor existing foci of neoplasia might instead produce a paradoxical
> promotion of tumorigenesis. The pharmaceutical form of the vitamin,
> folic acid, might affect the process in a manner that is distinct from
> natural forms of the vitamin, although this remains a speculative
> concept. Our limited understanding of this complex relationship is
> impeding efforts to move ahead with widespread folic acid
> fortification, but this delay may be necessary to ensure that such
> programs are instituted in a safe manner.
> 3.
> Circulating folate, vitamin B12, homocysteine, vitamin B12 transport
> proteins, and risk of prostate cancer: a case-control study,
> systematic review, and meta-analysis.
> Collin SM, Metcalfe C, Refsum H, Lewis SJ, Zuccolo L, Smith GD, Chen
> L, Harris R, Davis M, Marsden G, Johnston C, Lane JA, Ebbing M, Bønaa
> KH, Nygård O, Ueland PM, Grau MV, Baron JA, Donovan JL, Neal DE, Hamdy
> FC, Smith AD, Martin RM.
> Source
> Department of Social Medicine, University of Bristol, Bristol, United
> Kingdom. simon.col...@bristol.ac.uk
> Abstract
> BACKGROUND:
> Disturbed folate metabolism is associated with an increased risk of
> some cancers. Our objective was to determine whether blood levels of
> folate, vitamin B(12), and related metabolites were associated with
> prostate cancer risk.
> METHODS:
> Matched case-control study nested within the U.K. population-based
> Prostate testing for cancer and Treatment (ProtecT) study of prostate-
> specific antigen-detected prostate cancer in men ages 50 to 69 years.
> Plasma concentrations of folate, B(12) (cobalamin), holo-haptocorrin,
> holo-transcobalamin total transcobalamin, and total homocysteine
> (tHcy) were measured in 1,461 cases and 1,507 controls. ProtecT study
> estimates for associations of folate, B(12), and tHcy with prostate
> cancer risk were included in a meta-analysis, based on a systematic
> review.
> RESULTS:
> In the ProtecT study, increased B(12) and holo-haptocorrin
> concentrations showed positive associations with prostate cancer risk
> [highest versus lowest quartile of B(12) odds ratio (OR) = 1.17 (95%
> confidence interval, 0.95-1.43); P(trend) = 0.06; highest versus
> lowest quartile of holo-haptocorrin OR = 1.27 (1.04-1.56); P(trend) =
> 0.01]; folate, holo-transcobalamin, and tHcy were not associated with
> prostate cancer risk. In the meta-analysis, circulating B(12) levels
> were associated with an increased prostate cancer risk [pooled OR =
> 1.10 (1.01-1.19) per 100 pmol/L increase in B(12); P = 0.002]; the
> pooled OR for the association of folate with prostate cancer was
> positive [OR = 1.11 (0.96-1.28) per 10 nmol/L; P = 0.2) and
> conventionally statistically significant if ProtecT (the only case-
> control study) was excluded [OR = 1.18 (1.00-1.40) per 10 nmol/L; P =
> 0.02].
> CONCLUSION:
> Vitamin B(12) and (in cohort studies) folate were associated with
> increased prostate cancer risk.
> > ! Many cancer cells have a high requirement for folic acid and
> > ! overexpress the folic acid receptor. This finding has led to the
> > ! development of anti-cancer drugs that target the folic acid
> > ! receptor.[31]
> > ! A meta-analysis published in 2010 failed to find a statistically
> > ! significant cancer risk due to folic acid supplements.[32]
> > ! Some investigations have proposed good levels of folic acid may be
> > ! related to lower risk of esophageal, stomach, and ovarian cancers, but
> > ! the benefits of folic acid against cancer may depend on when it is
> > ! taken and on individual conditions. In addition, folic acid may not be
> > ! helpful, and could even be damaging, in people already suffering from
> > ! cancer or from a precancerous condition. Likewise, it has been
> > ! suggested excess folate may promote tumor initiation.[33] Folate has
> > ! shown to play a dual role in cancer development; low folate intake
> > ! protects against early carcinogenesis, and high folate intake promotes
> > ! advanced carcinogenesis.[34] Therefore, public health recommendations
> > ! should be careful not to encourage too much folate intake.[34]
> > ! Diets high in folate are associated with decreased risk of colorectal
> > ! cancer; some studies show the association is stronger for folate from
> > ! foods alone than for folate from foods and supplements,[35] Colorectal
> > ! cancer is the most studied type of cancer in relation to folate and
> > ! one carbon metabolism. One study concluded that there was not strong
> > ! support for an association between prostate cancer risk and
> > ! circulating concentrations of folate or vitamin B12. The researchers
> > ! noted that while elevated concentrations of vitamin B12 may be
> > ! associated with an increased risk for advanced stage prostate cancer,
> > ! that this was not true of folic acid and that the association between
> > ! B12 and cancer risk required examination in other large prospective
> > ! studies.[36]
> > ! Most epidemiologic studies suggest diets high in folate are associated
> > ! with decreased risk of breast cancer, but results are not uniformly
> > ! consistent. One broad cancer screening trial reported a potential
> > ! harmful effect of much folate intake on breast cancer risk, suggesting
> > ! routine folate supplementation should not be recommended as a breast
> > ! cancer preventive,[37] but a 2007 Swedish prospective study found much
> > ! folate intake was associated with a lower incidence of postmenopausal
> > ! breast cancer.[38] A 2008 study has shown no significant effect of
> > ! folic acid on overall risk of total invasive cancer or breast cancer
> > ! among women.[39] Folate intake may not have any effect on the risk of
> > ! breast cancer but may
Trawley wrote:
> You have no comment on the wikipedia article, just another
> reference that we cannot read. According to the quoted text
> there is only 95 percent confidence in the result. That is
> not enough to override other contradicting studies.
The problem with the Wikipedia article is that you only link the
article, but not the studies that the article referenced.
First of all the Wiki article was very explicit about the concerns of
folic acid and cancer.
"In addition, folic acid may not be helpful, and could even be
damaging, in people already suffering from cancer or from a
precancerous condition. Likewise, it has been suggested excess folate
may promote tumor initiation.[33] Folate has shown to play a dual role
in cancer development; low folate intake protects against early
carcinogenesis, and high folate intake promotes advanced
carcinogenesis.[34] Therefore, public health recommendations should be
careful not to encourage too much folate intake.[34]" [I've provided
the references below]
Secondly many of the studies cited did not differentiate between folic
acid supplements and folate from foods. It's the folic acid from
supplements that's being singled out in this thread. Folate from
natural foods is a different matter. The Wiki even cites this study
that shows just this point:
"Recently, a clinical trial showed daily supplementation of 1 mg of
folic acid increased the risk of prostate cancer, while dietary and
plasma folate levels among vitamin nonusers actually decreased the
risk of prostate cancer.[41]"
Now one study ( a meta study of a number of random controlled trials)
was cited in that did not find increased issues with folic acid
supplement users [32], but also no benefits were noted.
Note that these trials only lasted an average 5 years and they did
not go looking for problems.
Contrast this paper with this study [1] where the actually did
Colonoscopies and looked for problems before folks would have noticed
anything.
The found:
"A 67% increase in Advanced Colorectal Adenomas in the group taking
the folic acid supplement compared to placebo.
A 132% increase of developing 3 or more adenomas in the group taking
folic acid."
Animal studies, where variables can be more tightly controlled have,
have shown that folic acid and cancer is concerning. That's a big
smoking gun in this discussion.
Trawley wrote:
> Then there is the presumed benefit of taking folic acid in preventing
> health problems in the developing fetus. You need much more
> convincing data than has been shown so far to say pregnant women
> should not take this supplement.
The studies on folic acid and cancer Did not use pregnant women. Where
did you get that idea.
Any women planing on getting pregnant women should make absolutely
certain she's obtaining adequate folate - even it that means taking
supplements.
Other than a possible young type 1 female, I doubt anyone else fits
that description here.
Randy
Refs:
1.
A 67% increase in Advanced Colorectal Adenomas in the group taking the
folic acid supplement compared to placebo.
A 132% increase of developing 3 or more adenomas in the group taking
folic acid. [a][b]
32.
Clarke R et. al. (2010). "Effects of Lowering Homocysteine Levels
With B Vitamins on Cardiovascular Disease, Cancer, and Cause-Specific
Mortality Meta-analysis of 8 Randomized Trials Involving 37 485
Individuals". Archives of Internal Medicine 170 (18): 1622–1631. doi:
10.1001/archinternmed.2010.348. PMID 20937919.
33.
Kim YI (1 November 2004). "Will mandatory folic acid fortification
prevent or promote cancer?". Am J Clin Nutr 80 (5): 1123–8. PMID
15531657.
^ a b Ulrich, CM (2007). "Folate and cancer prevention: a closer look
at a complex picture". The American journal of clinical nutrition 86
(2): 271–273. PMID 17684194.
34.
^ a b Ulrich, CM (2007). "Folate and cancer prevention: a closer look
at a complex picture". The American journal of clinical nutrition 86
(2): 271–273. PMID 17684194.
41.
Figueiredo, JC; Grau, MV; Haile, RW; Sandler, RS; Summers, RW;
Bresalier, RS; Burke, CA; McKeown-Eyssen, GE et al (2009). "Folic Acid
and Risk of Prostate Cancer: Results From a Randomized Clinical
Trial". Journal of the National Cancer Institute 101 (6): 432–5. doi:
10.1093/jnci/djp019. PMC 2657096. PMID 19276452.
Gys wrote:
> nice to see you back posting. For a few seconds I wondered if our mutual
> friend <Empty> Boob </Emprty>spoiled the fun for you.
Nope still here. I finally realized that Wes's advice was wise. Still
having fun and Glad to see deT, a new balanced poster. We are in
desperate need for more like him.
Also, I didn't realize we had a "hidden agenda". If you figure out
what it is, please let me know.
Finally - please stay active here. Sometimes I fear you will take off
on that bike, never to return.
> I smoked from about 6 years old. I was born in the Rotterdam Harbour area.
> Every body smoked. Even the cat. My grandfather smoked till he was 95. I
> smoked till 1996 2 packs a day. That is packs of dark tobaco to make your
> own (40) cigarettes.
> I don't have any cancers, nor my grandfather. My sister just dies of lung
> cancer. She never smoked. Statistics is not for sissies.
> Causation is no corelation. All dokters are idiots paid by big pharma,
> so they will do anything to deprive us from cheap and effective
> solutions. Supplements and vitamins are essential for your health. The
> more you take the better of course.
> Gys
> Beta-carotene, selenium and folic acid - taken up to three times their
> recommended daily allowance, these supplements are probably harmless.
> But taken at much higher levels as some supplement manufacturers
> suggest, these three supplements have now been proven to increase the
> risk of developing a host of cancers.
> "It's not that these nutrients are toxic - they're essential and we need
> them, but we need them in a certain balance," says Tim Byers, MD, MPH,
> professor of epidemiology at the Colorado School of Public Health and
> associate director for prevention and control at the University of
> Colorado Cancer Center.
So what's new?
As sse Great Poet put it:
"Too little or too much
Decides who wears the crutch".
> Byers is senior author of a commentary recently published in the Journal
> of the National Cancer Institute that discusses the clinical and policy
> implications of the increased cancer risk from high dose dietary
> supplements.
> We have a window into less than half of the biology of what these
> nutrients are doing," Byers says. "We say generalized things about them,
> calling them an antioxidant or an essential mineral, but true biology
> turns out to be more complex than that. The effects of these supplements
> are certainly not limited to the label we give them. And, as we've seen,
> sometimes the unintended effects include increased cancer risk."
> "We need to do a better job as a society in ensuring that the messages
> people get about value versus risk is accurate for nutritional
> supplements," Byers says. "My conclusion is that taking high doses of
> any particular nutrient is more likely to be a bad thing than a good
> thing."
>> In the case of folic acid, I've taken far above normal amount of it
>> daily for the last 6 years with no adverse effects. Apparently it
>> only affects some people, if that.
> I'd really recommend a tutorial on stats and probability.
So, get with it!
BUT *do* start with a couple of remedial courses on Math & Science 101.
The data
> don't show that Everyone that takes excess (above RDA) of folic acids
> has problems, but a significant number do.
To once again quote sse Great Poet:
"Too little or too much
Decides who wears the crutch."
It's that simple.
> Many have made the same claims of smoking and health. Even me in my
> younger, smoking days.
Figures.
Yours truly OTOH never lost sight of reality even when - in his younger days -he was smoking like a chimney.
Do you think that's a valid refutation of the
> data on cigarettes.
ANYONE of relatively sound mind, who has smoked for a number of years ever needed any data to know cigarettes are unhealthy.
