Why are fats important?
Plants and animals cannot live without fats. The fats in seeds provide energy for the plants to germinate. In animals (including us), fats are an essential part of cell membranes, and are used for the production of some hormones and other regulatory molecules. Fat tissue just under our skin helps regulate body temperature. If that were not important enough, a complex process involving glucose (see page 4) breaks down fatty acids to generate the constant stream of energy we require to keep our bodies functioning and moving.
In the foods we eat, fats contribute to mouthfeel and our perception of flavor, and they are necessary for the absorption of fat-soluble vitamins (A, D, E, and K).
Isn’t eating too much fat bad for us?
This statement is an oversimplification of a complex issue. Let me tackle some key points:
First, let’s talk about body weight. Eating too many calories, regardless of whether they come from fat, carbohydrate, or protein, causes weight gain. A calorie is a unit of energy. While protein and carbohydrates have four calories per gram, fat has nine. (For the record, alcohol has seven calories per gram.)
A diet high in fat may therefore lead one to eat more calories in a shorter period of time than eating a diet high in protein or carbohydrate. When we look at large groups of individuals, however, total fat intake (high or low) does not seem to relate to body weight. It’s total calories that matter, regardless of which macronutrient they come from.