If there has ever been a component of the human diet that has been debated and misunderstood, well beyond normal limits, it would have to be fats.

Media reports filled with new findings on the benefits or dangers of certain fats, and food manufactures with their claims, complicate the controversy even further. With all the negative implication of fats, we often overlook the essential role they play in so many of our body’s chemical reactions.

1) Fats provide us a substantial energy supply that may be used by the body in times of need.

2) Fats carry “fat soluble” vitamins A, D, E and K throughout the body. These vitamins, needed for good health, can’t dissolve in water, so they can’t be taken into cells without first mixing with “lipids” (fats).

3) Fats are necessary for many chemical reactions within the body. Fats are needed for proper growth in children and healthy cell membranes, including healthy skin. Fats are also responsible for the production of “prostaglandins.” These are hormone like substances that regulate a number of the body’s processes.

4) Fats make eating more enjoyable by adding aroma, flavor and texture to food, thus making it more palatable. Since fats are slow to digest, they satisfy hunger, even after proteins and carbohydrates have left the stomach. Also, fats stimulate the walls of the intestines to release a substance called “cholecystokinin,” which suppresses appetite, and helps prevent hunger.

5) Fats acts as temperature regulators. About half of one’s body fat is stored just below the skin’s surface. This is known as “subcutaneous fat.”

This layer of fat acts as insulation. That’s why thin people tend to be more sensitive to cold, while over weight people tend to be more bothered by heat. When it comes to fat consumption, only water and carbohydrates are more plentiful in the typical American diet.

According to the United States Department of Agriculture, 35 to 40 percent of calories consumed in the average American diet come from fats. Fatty acids are one of the major building blocks of fat. Fats that are made up of one or two fatty acids and a glyceride are know as monoglycerides and diglycerides. Three fatty acids plus a molecule of glycerin are known as triglycerides, which make up about 95 percent of dietary fat and 90 percent of body fat.

In this column we won’t go over the chains of carbon atoms, oxygen and hydrogen atoms, and how they behave to produce fats. The average consumer doesn’t need to know, nor could care less about the chemical sources of fats. What is important to know, for good health, is a fat’s level of “saturation.”

These three fats are usually referred to as “saturated,” “monounsaturated” and “polyunsaturated.”

The worst of these three is “saturated” fat. These fats are solid at room temperature and when refrigerated, so it stands to reason if these fats stay solid at moderate temperatures, they’ll stay solid in your blood stream too.

Saturated fats interfere with the removal of cholesterol from the blood and therefor play a role in raising blood cholesterol levels. Sources of these fats usually come from animal products like beef, pork, cheese, butter, ice cream and plant sources like coconut and palm oils.

The second type of fat, which is actually healthful, is “monounsaturated” fat. These fats are liquid at room temperatures and semi-solid when refrigerated. Monounsaturated fats are heart healthy because they help lower LDL (bad) cholesterol, while raising HDL (good) cholesterol levels. Olive oil is the best source of monounsaturated fats.

High consumption of olive oil in Mediterranean countries is believed to be one of the reasons these countries have lower levels of heart disease. Other sources of monounsaturated fats include peanut oil, rapeseed oil, hazelnuts, almonds, Brazil nuts, cashews, avocado and sesame seeds.

The third and most beneficial type of fats are ”Polyunsaturated fats.” These too, lower LDL (bad) cholesterol levels while raising HDL (good) cholesterol. Polyunsaturated fats also provide beneficial omega-6 and omega 3 fatty acids.

These fats are considered “essential,” because our bodies don’t produce them. We therefore must acquire them from our diet. Polyunsaturated fats are liquid at room temperature and when refrigerated. Good sources of polyunsaturated fats include soybean oil, corn oil, safflower oil and fatty fish like salmon, mackerel, herring and trout.

In fact, we know fish oil is liquid when refrigerated, or cold water fish’s blood wouldn’t be able to flow. Use these tips to choose the right fats for better health.

Diet or exercise question?

E-mail me at dwcrocker77@gmail.com or visit fitness4yourlife.org David Crocker of Landrum has served as strength director of the Spartanburg Y.M.C.A., strength coach S.C. State champion girls gymnastic team, USC-Spartanburg baseball team, Converse college equestrian team, lead trainer to L.H. Fields modeling agency, taught four semesters at USC-Union. David was also a regular guest of the Pam Stone radio show.