The disastrous "low-fat diet" dogma of the last half century has led to a devastating drop in most people's intake of healthy saturated fats, including MCTs.
Besides coconuts, coconut oil and palm kernel oil, small amounts of MCT can be found in butter and other high-fat dairy products from grass-fed cows and goats. MCTs can be divided into four groups based on their carbon length, which ranges from six to 12 carbons. As a general rule, the shorter the carbon chain, the more efficiently the MCT will be turned into ketones, which are an excellent source of energy for your body — far preferable to glucose, as ketones produce far less ROS when they are metabolized to produce ATP.
My personal preference is straight caprylic acid (C8), as it converts to ketones far more rapidly than the more common C8 and C10 mixtures. Since MCT oil, and especially caprylic acid (C8) oil, is a far more concentrated source than coconut oil, it's often appropriate for clinical uses, which include: