Let's start with some basic science. What we know as fat exists both in the body and in foods. It consists mostly of triglycerides with traces of fatty acids, phospholipids, and sterols, all of which fall into a class of substances called lipids. Lipids and fats play important roles in the body and in the diet. Lipids are an essential component in all the body's cells.
Body fat serves as an energy reserve and protective cushioning for vital organs.
It also helps regulate body temperature and is needed for hormone production and regulation. Fats also add flavor to foods and provide many of the textures we find desirable. Fats tend to give a longer feeling of fullness after being consumed because they are slow to digest. There is a growing concern about high fat diets because they have been linked to increased risk of colon, breast, and prostate cancers, and many other diseases. Eating too much fat increases the risk of obesity which is a risk factor for some cancers, heart disease, hypertension, and diabetes.