Although you may not be aware of the usefulness of the lecithin
molecule, your body knows very well how to use it! Lecithin is a
constituent of cell membranes, specifically a phospholipid. It is
like a hydrophilic pinhead with two hydrophobic fatty acid legs,
which are essential properties for the formation of emulsions.

Besides cells in the human body, lecithin is mainly found in egg
yolks, soybeans, liver, and wheat germ. The pharmacist Théodore
Gobley isolated and described egg lecithin for the first time in
1847. Gobley gave it the name lekithos, the Greek word for egg
yolk. He then spotted the group of molecules in many parts of
animal bodies and in large quantities in the bile, blood and brain.

Lecithin found in eggs remains the most popular for making
mayonnaise or hollandaise sauce, but industry usually extracts it
from soy. During the manufacturing process, the soybean is first
cooked, then crushed and finally precipitated by alcohol.

Lecithin is found in margarines and infant formula where it acts
as an emulsifier. It is also found on the list of ingredients for ice
preparations, such as sorbets and ice milk, where it allows fat
to remain soluble in a high-water compound.

The body has the ability to manufacture lecithin, but if you want to
use this product as a supplement, like fats, it provides the equivalent
of 9 kilocalories per gram.