Lecithin is an essential fat that may be useful in treating special cases of liver disease, gallbladder disease and dementia caused by Alzheimer's disease, according to WebMD. Many physicians approve of using lecithin as treatment, but as of 2015, conclusive studies have not been conducted to prove such claims.
In most cases, lecithin users experience few to no side effects, according to WebMD. Possible side effects include digestive issues, such as diarrhea, nausea and abdominal pain. Women who are pregnant or breastfeeding should consult a physician before taking lecithin or avoid it altogether as thorough studies in such women have not been conducted.
When ingested, lecithin converts into acetylcholine, which is a neurotransmitter that runs through the central nervous system and affects attention and arousal, as stated by WebMD and About.com. Along with medications and supplements, lecithin may also be found in such food items as soybeans and egg yolks as well as food additives. Less common sources include certain moisturizers and medicated eye drops.
Less common uses for lecithin include lowering high cholesterol levels in people taking statins, reducing such manic symptoms as delusion, and treatment of various skin conditions, according to WebMD. There is little evidence to support these claims.