Lecithin is a group of chemicals that are related. It isn’t a single chemical. Lecithins belong to a larger group of compounds called phospholipids. These are important parts of the brain, blood, nerves, and other tissues. Phospholipids are also a part of cell membranes.  

The body uses lecithin to move fats and in the metabolic process. Lecithins turn into choline in the body. They help make the neurotransmitter acetylcholine.

Many people know lecithin as the oily film on their frying pan when they use a nonstick cooking spray.

There may be benefits that have not yet been proven through research.

Lecithin is used to treat dementia. It’s also used to treat Alzheimer's disease. And it is used to treat gallbladder disease. It may also help treat fatty liver (hepatic steatosis) in people on long-term parenteral nutrition. But the role of lecithin is not well defined and confirmed.

Lecithin comes in capsules, liquid, and granules. There is no recommended intake amount.

Foods that have lecithin include:

• Egg yolks
• Soybeans
• Wheat germ
• Peanuts
• Liver

Signs of lecithin deficiency aren’t clear. They are more likely to be caused by choline deficiency, not lecithin.

Choline deficiency is rare. It may lead to: 

• Muscle damage
• Liver problems
• Kidney damage

In normal doses, lecithin may cause side effects. These can include stomach aches, diarrhea, or loose stools. It isn’t known what symptoms would occur if you take too much lecithin.

Women who are pregnant or breastfeeding should talk to their healthcare providers before taking any supplements.

There are no known food or medicine interactions with lecithin.