Lecithin is a natural fat emulsifier and a source of brain-nourishing phosphatidylcholine (PC). It's widely recommended by nutritionists for supporting circulatory and heart health, immune strength and liver health. While most lecithin supplements are soy derived, eggs are also a great source. Swanson's new Egg Yolk Lecithin is naturally derived from high-quality eggs and contains only 5 mg of cholesterol per serving.