Soy lecithin is a mixture of beneficial compounds extracted from soybeans. The compounds found in lecithin, which are easily obtained in a well-balanced diet, have many positive effects on the body. Many claims have been made that soy lecithin supplements are beneficial to brain health, but research data as of July 2011 don't back up these claims.
Soy lecithin is a mixture of phospholipids that are isolated from soybeans oil. Phospholipids are composed of a diglyceride, a phosphate group and a small organic molecule. These properties impart both charged and uncharged character to phospholipds and enable them to form lipid bilayers that make up cell membranes. The main phospholipid in lecithin is phosphatidylcholine, but it also contains phosphatidylinositol, phosphatidylethanolamine, and phosphatidic acid. The most widely available form of lecithin is isolated from soybeans, but it can also be extracted from sunflower oil or even egg yolks.
Soy lecithin is nontoxic, inexpensive and has many uses as a health food supplement in drugs, in manufacturing as a lubricant, and as an emulsifier in food production. According to the "Journal of Nutritional Science and Vitaminology," compounds within soy lecithin inhibit the absorption of dietary cholesterol. However, a recent study in the journal "Nature" reports that bacteria in the intestines might metabolize components within soy lecithin to promote certain types of cardiovascular disease.
Effects on Brain
Many claims have been made on the effects of soy lecithin on the nervous system, such as treating Alzheimer's disease and multiple sclerosis, but most are not backed up by scientific studies. Some research touts the benefits of soy lecithin on memory and cognitive function, such as a report in the "Journal of Clinical Biochemistry and Nutrition." However, some research in "Brain Research Bulletin" has suggested that consumption of soy lecithin might lead to brain damage by inhibiting nerve cell connections and total neural function.
According to Vanderbilt University, those who consume a well-balanced diet do not need to take soy lecithin supplements, but many choose to because of the many reported health benefits. Soy lecithin supplements are inexpensive and are available over-the-counter as a liquid, in capsules or in granules. Some possible side effects of soy lecithin supplements include mild diarrhea or intestinal discomfort. The recommended dosages must be followed on the package to minimize side effects.
- "Journal of Nutritional Science and Vitaminology"; "The effect of various phospholipids on plasma lipoproteins and liver lipids in hypercholesterolemic rats"; T. Iwata et al.; February 1993
- "Brain Research Bulletin"; "Perinatal dietary supplementation with a soy lecithin preparation: effects on development of central catecholaminergic neurotransmitter systems"; J.M. Bell et al.
- "Journal of Clinical Biochemistry and Nutrition"; "Soybean-derived phosphatidylserine improves memory function of the elderly Japanese subjects with memory complaints"; A. Kato-Kataoka at al.; November 2010