Wednesday, August 27, 2014
Wisdom Wednesday: Quasi-vitamins
Traditional vitamins were discovered during the first half of the last century. There was an initial association between diet and health status that led early researchers to identify these essential nutrients. Until identified and labeled as vitamins, these chemicals were called “unidentified growth factors”. That term is still used today.
The term “vitamin” is specific for animal species, stage of development, and/or particular conditions of the physical environment and diet. For example, most primates (other than humans) can make vitamin C, so for them, it is not a vitamin. Guinea pigs, like humans, cannot make vitamin C, which is why they became so popular in research.
Of course, some of our traditional vitamins are not really vitamins. Vitamin D is a hormone not a vitamin, and is manufactured by skin cells when exposed to sunlight.
The quasi-vitamins meet the criteria of a vitamin for only a few species or only under certain conditions, and are not accorded the full status of a vitamin. Under the heading of only a few species are choline, carnitine, and inositol.
Choline is required in the diets of young poultry for optimal growth and freedom of leg disorders. It occurs in foods in the form of phosphatidylcholine (also called lecithin). The best food sources are egg yolk, glandular meats (liver, kidney, brain), soy, wheat germ, and peanuts.
Lecithin mobilizes lipids (fat) in the body. I used phosphatidylcholine for many years to raise HDL levels, when I thought that was of nutritional value. Today, I use it in concert with Silymarin to reduce inflammation in the liver. I also use it in support of brain function and neurotransmitter production. A low HDL level can indicate poor lecithin production and result in impaired fat metabolism.
Carnitine is required for the growth of certain insects. It is found in milk, yeast, and many animal products. In humans, it is manufactured from two essential amino acids – lysine and methionine. It stimulates the oxidation of long chain fatty acids (like omega 3, 6, 7 and 9 fatty acids), especially in heart muscle. It actually transports these fats from the cytosol into the mitochondria of the cell to be used for energy.
Although it has several chemical forms, L-carnitine is the popular form of supplementation. Because it is easily manufactured from common amino acids, deficiency is rare, expect in vegetarian populations and people with restricted protein intake. An obese vegetarian is an excellent candidate for L-carnitine supplementation.
Inositol is required for the optimal growth of fish and to prevent intestinal lesions in gerbils. It can be synthesized from glucose by humans and many other mammals. The richest sources are plant seeds. However, in plants it is most commonly in the form of phytic acid. In cereal grains, this accounts for the total content of phosphorus. Phytic acid is poorly digested and considered a goitrogen (chemical that impairs thyroid function).
I use inositol to treat neuropathy. It opens the blood-brain barrier, allowing more nutrients into the nervous system to speed healing. I prefer to use St. John’s Wort in the treatment of neuropathy but is contraindicated with some medications and other times will test less favorably than inositol. Patients with MS cannot synthesize inositol. Adding large daily doses to the diet of MS patients dramatically improves their neurological function. It is quite sweet, much like the glucose we make it from, so I often have patients sprinkle it on food.
THE BOTTOM LINE:
These quasi-vitamins can be very valuable supplements when used appropriately. Although the average American should not need to supplement any of these “growth factors”, specific conditions readily respond to their addition to the diet. Remember, all vitamins were, at one time, “unknown growth factors” and there are many more yet to be discovered.