When medical researchers use the term "lecithin", they are referring to a purified substance called phosphatidylcholine (PC). Supplements labeled as "lecithin" usually contain 10-20% PC. Relatively pure PC supplements are generally labeled as "phosphatidylcholine". PC best duplicates supplements used in medical research.
Most commercial lecithins contain various amounts of other phospholipids such as phosphatidylserine and phosphatidylethanolamine.
Source
Choline, a lipotropic molecule and the major constituent of phosphatydyl choline, is also available by itself (without the "phosphatidyl" group) in foods and supplements. It is found in soybeans,
liver and other animal organs,
bile, oatmeal, cabbage, and cauliflower. Egg yolks, meat, and some vegetables contain PC.
Lecithin (containing 10-20% PC) is added to many processed foods in small amounts, for the purpose of maintaining texture consistency.
Most commercial lecithin is derived from soybeans.
Choline is added as an ingredient in some multivitamin products as well as those specifically designed for the
liver or
gastrointestinal conditions. Choline is also a precursor to the
neurotransmitter acetylcholine, and is often added to products designed to improve memory or
depression.
Commercial lecithin supplies choline,
inositol, phosphoric acid and
fatty acids to the diet.
Choline can also be found in stable salt forms such as choline bitartrate.
Function; Why it is Recommended
PC acts as a supplier of
choline. Choline is now considered an essential nutrient, needed for cell membrane integrity and to facilitate the movement of fats in and out of cells. It is also a component of the
neurotransmitter acetylcholine and is needed for normal brain functioning, particularly in infants. For this reason, PC has been used in a number of preliminary studies for a wide variety of neurological and psychiatric disorders [
Benjamin J, Levine J, Fux M, et al. Double-blind, placebo-controlled, crossover trial of inositol treatment for panic disorder. Am J Psychiatry 1995;152: pp.1084-6.], though not every study suggests that supplemental choline is capable of reaching the brain [
Dechent P, Pouwels PJW, Frahm J. Neither short-term nor long-term administration of oral choline alters metabolite concentrations in human brain. Biol Psychiatry 1999;46: pp.406-11]. Choline participates in many functions involving cellular components called phospholipids.
Choline is a vitamin that is lipotropic (has an affinity for
lipids - fats). Lipotropics are fat metabolism assisting agents. As a lipotropic agent it is helpful in moving fat out of the
liver into the
bile.
As a precursor to betaine, choline is also involved in methylation of homocysteine as well as DNA.
Lecithin, with other phospholipids, is essential for every cellular and sub-cellular membrane in the body, especially the brain and
central nervous system. Lecithin helps to regulate fat and
cholesterol metabolism and is beneficial in
atherosclerosis,
hypertension and
diabetes.
Phosphatidyl
choline has been used in connection with the following conditions:
Side-Effects
In high amounts, pure
choline can make people smell like fish, so it's rarely used, except in the small amounts found in multivitamin supplements.