Lecithin is a waxy material found in the protective sheath that surrounds nerve fibers. It contains a substance known as ‘choline’, which can be found in egg yolks, liver, beef, and soybeans. Cholesterol is a type of fat found in foods from animal sources and is produced in the liver. High levels of cholesterol in the blood are associated with an increased risk of cardiovascular disease. Some researchers have attempted to lower cholesterol levels and improve memory using large doses of choline and lecithin, but they’ve had limited success. Under normal circumstances, choline and lecithin supplements aren’t necessary, because the body naturally manufactures choline. Ingesting large amounts of choline or lecithin may have toxic effects. The American Academy of Pediatrics recommends that infant formula supply at least seven milligrams of choline per 100 calories, which is the same amount present in human breast milk.