Rather than getting into a pissing contest, why not actually look at the
facts? The answer is a qualified "yes" and a much bigger "no".
Yes it is apparently (just barely) possible. Wikipedia reports a single
death from vitamin D toxicity in the USA in 2004. No, it is hugely
improbable, but short of death, vitamin D-3 overdoses can conceivably
cause permanent damage. However, the amount of D-3 required for this is
so massive it is extremely unlikely to occur. NO vitamin D-3 toxicity
has EVER been observed even at lifelong intake levels of 20,000 IU a
day. Your own body will produce that amount if exposed to a moderate
amount of sunlight.
It is much more likely that you suffer from a vitamin D-3 deficiency.
Perhaps two third of everyone in the USA, Canada, and Europe are
deficient. Since this thread as about the possibility of a fatal
overdose, I leave it at that.
Vitamin Poisoning
"In the United States, overdose exposure to all formulations of
"vitamins" was reported by 62,562 individuals in 2004 (nearly 80%(~78%,
n=48,989) of these exposures were in children under the age of 6),
leading to 53 "major" life-threatening outcomes and 3 deaths(2 from
Vitamins - D and E; 1 from polyvitaminic type formula, with iron and no
fluoride)."
http://en.wikipedia.org/wiki/Vitamin_poisoning
"Vitamin Toxicity "
The symptoms of vitamin D toxicity are nausea, vomiting, pain in the
joints, and loss of appetite. The patient may experience constipation
alternating with diarrhea, or have tingling sensations in the mouth. The
toxic dose of vitamin D depends on its frequency. In infants, a single
dose of 15 mg or greater may be toxic, but it is also the case that
daily doses of 1.0 mg over a prolonged period may be toxic. In adults, a
daily dose of 1.0-2.0 mg of vitamin D is toxic when consumed for a
prolonged period. A single dose of about 50 mg or greater is toxic for
adults. The immediate effect of an overdose of vitamin D is abdominal
cramps, nausea and vomiting. Toxic doses of vitamin D taken over a
prolonged period of time result in irreversible deposits of calcium
crystals in the soft tissues of the body that may damage the heart,
lungs, and kidneys.
In all cases, treatment of vitamin toxicity requires discontinuing
vitamin supplements. Vitamin D toxicity needs additional action to
reduce the calcium levels in the bloodstream because it can cause
abnormally high levels of plasma calcium (hypercalcemia). Severe
hypercalcemia is a medical emergency and may be treated by infusing a
solution of 0.9% sodium chloride into the patient's bloodstream.
The prognosis for reversing vitamin toxicity is excellent for most
patients. Side effects usually go away as soon as overdoses are stopped.
The exceptions are severe vitamin D toxicity, severe vitamin A toxicity,
and severe vitamin B6 toxicity. Too much vitamin D leads to deposits of
calcium salts in the soft tissue of the body, which cannot be reversed.
http://medical-dictionary.thefreedictionary.com/Vitamin+Toxicity
"Can you take too much vitamin D?"
http://www.vitamind3-cholecalciferol.com/vitamin-d-overdose.htm
"Vitamin D Toxicity"
The amount of supplemental vitamin D3 that would produce toxicity in
healthy individuals is not known exactly. It would certainly vary from
individual to individual.
Evidence from accidental overdose of vitamin D in individuals and
communities has given some indications.
It appears from this evidence that human toxicity starts at around
40,000 IU per day, but only when taken continuously for at least three
months.
Some people have taken much larger doses than this, for even longer
periods of time, without experiencing toxicity.
www.vitamind3-cholecalciferol.com/vitamin-d-toxicity.htm
"Can You Overdose on Vitamin D? It's Harder Than You Think"
Cases of vitamin D toxicity . . . all involve intake of (greater than
or equal to) 40,000 IU/d
Another study gave pregnant women 100,000 IU's per day for the entire
length of their pregnancy. The study concluded, "Thus, there is no
evidence in humans that even a 100,000 IU/d dose of vitamin D for
extended periods during pregnancy results in any harmful effects."
http://www.easy-immune-health.com/Overdose-on-Vitamin-D.html