Lipids, often referred to as fats, are one of the four macromolecules required by all living organisms. The Elmhurst College Virtual Chembook states that the primary function of lipids is to store energy for later use.
The Elmhurst College Virtual Chembook splits lipids into two classifications: those found in the blood and those stored in adipose tissue. Lipids in the blood are metabolized for use in cellar functions or used to synthesize brain and nerve tissues. Stored as adipose tissue, lipids provide protection by cushioning vital organs, act as structural support and insulate organisms from temperature fluctuations and heat loss.