Fats, Fish Oil and Omega-3-Fatty Acids

Medical Author: Dennis Lee, M.D.
Medical Author: Gregory Thomas, M.D.

What is fat?

Fat (also known as lipid), is one of the three classes of nutrients; the other two are proteins and carbohydrates. The major function of fat is to provide energy for the body. Pound per pound, fat contains more energy (calories) than protein and carbohydrates. There are three types of fat:

  1. triglycerides,
  2. cholesterol, and
  3. phospholipids.

Triglycerides are where most of the fat calories are stored. In addition to providing energy, fat also serves other functions, for example, cholesterol and phospholipids are components of cell membranes and sheaths surrounding nerve cells. Cholesterol is also important for the production of bile acids and other hormones (such as sex hormones and adrenal hormones).