Fatty Acid

Fatty acids are carboxylic acids with long aliphatic chains, which can be either saturated or unsaturated. They are a key component of the lipids that make up cell membranes and are also important for energy storage. Fatty acids are derived from triglycerides or phospholipids. When they are not attached to other molecules, they are known as "free" fatty acids.

Structure

Fatty acids are composed of a chain of carbon atoms, with a carboxyl group (COOH) at one end. The carbon chain can vary in length, and may be saturated (with no double bonds between the carbon atoms) or unsaturated (with one or more double bonds). Saturated fatty acids are solid at room temperature, while unsaturated fatty acids are liquid.

Types of Fatty Acids

There are many different types of fatty acids, but they can be broadly divided into two categories: saturated fatty acids and unsaturated fatty acids.

Saturated Fatty Acids

Saturated fatty acids have no double bonds between the carbon atoms. This means that they are fully "saturated" with hydrogen atoms. Examples of saturated fatty acids include palmitic acid and stearic acid.

Unsaturated Fatty Acids

Unsaturated fatty acids have one or more double bonds in their carbon chain. These double bonds can cause the fatty acid molecules to bend, preventing them from packing together tightly and making them liquid at room temperature. Examples of unsaturated fatty acids include oleic acid and linoleic acid.

Functions

Fatty acids have several important functions in the body. They are a major source of energy, as they can be broken down in the mitochondria to produce ATP, the body's main energy currency. They are also used to build cell membranes and for the synthesis of hormones and other signaling molecules.

Dietary Sources

Fatty acids are found in many foods, including meat, dairy products, and oils. The body can also synthesize most fatty acids from carbohydrates and proteins, although there are two fatty acids, linoleic acid and alpha-linolenic acid, that must be obtained from the diet.

Health Effects

The type and amount of fatty acids in the diet can have significant effects on health. A diet high in saturated fatty acids can increase the risk of heart disease and stroke, while a diet rich in unsaturated fatty acids can have protective effects.