Assalamuailkum,
Soy lecithin is found naturally in soybeans. It is a thickening agent for fatty foods. It is used for its emulsifying and antioxidant effects, it could help to reduce cholesterol and aid memory. Commonly found in candy bars and chocolate. Just incase you are not familiar with Soybean (U.S.) or soya bean (UK), it is a species of legume native to Eastern Asia. As all beans the soy bean is a complete protein. I hope this info is useful to you