Fat Facts and Fads

American Fitness, May, 1999 by Nancy Clark

Contrary to previous notions, incorporating the right types of fat into your diet can actually improve your performance--mentally and physically.

Confusion abounds regarding dietary fat. A few years ago, we were told to avoid fat like the plague. Today we hear balancing fat into our diets is OK. This article will help clarify some facts about fats.

What is the role of fat in the athlete's diet?

A concentrated source of energy, fat helps athletes who expend high amounts of energy to fuel themselves adequately. Without dietary fat, consuming enough calories to maintain strength and stamina can be difficult.

In addition to providing calories, dietary fat is needed to replenish intramuscular fat stores (fat stored within the muscle and used to fuel extended exercise). A study with runners who ate equal amounts of calories from a low fat diet (15% of total calories) or a higher fat diet (38%) performed better with higher fat intake. This improvement is likely related to better intramuscular fat stores. The runners did not gain weight, dispelling the popular myth "eat fat, get fat." They also experienced a positive increase in their "good" HDL cholesterol.

Dietary fat is also important for mental health. Lack of certain essential fats (fats your body can't produce) have been associated with depression. These essential fats (found in fish, canola oil and flaxseed oil) are an important component of nerve cells. Too little can affect brain/nervous system functions and contribute to depression.

If I eat fat, will I get fat?

Yes, excess calorie and fat intake will allow your body to collect fat. But fat that fits within your daily calorie allowance gets burned. Some people are better able to lose body fat when they eat a little fat with each meal because fat satisfies and curbs the appetite. Fat takes longer to digest than carbohydrates and helps keep you from feeling hungry.

If I eat fat, will I increase my risk of heart disease?

The answer depends on what kind of fat you eat. For health reasons, you want to eat more unsaturated liquid fats found in plants, nuts, oil and fish rather than hard saturated fats found in meats, butter and other animal foods. When appropriately included in the diet, unsaturated fats do not elevate your risk of heart disease. Also, limit processed foods such as crackers, commercially baked goods and stick margarines that list partially hydrogenated vegetable oils among the ingredients on their food labels. Hydrogenation converts the "good" oil into harder fat, which has characteristics of saturated fats.

Heart disease is associated with not only dietary fat but also serum triglycerides, which are fats that circulate in the blood stream and provide energy for your body. They are elevated by dietary factors (particularly fatty foods, excess sugary foods and alcohol). People who have a high carbohydrate diet --including excessive hard candies, fat-free cookies and fat-free frozen yogurt--often have high triglyceride levels. It's better to satisfy your appetite with healthful fat calories than avoiding all fats, which can leave you feeling unsatisfied and hankering for sugar. If you have elevated triglycerides, you can likely lower them by eating more fish rich in unsaturated (omega-three) fatty acids, drinking less alcohol, losing weight (if you are overweight), eating less refined sugar and exercising regularly.

How much dietary fat is too much?

The typical American eats a diet with about 34% of calories from fat. The American Heart Association recommends a diet which slightly restricts total fat to less than 30% of calories, and saturated fats like meats and cheeses to less than 10% of calories.

Health-conscious athletes sometime believe if low fat is good, than no fat is better. This may not be the case. A one-year study of men with high cholesterol examined the cholesterol-lowering effects of diets with 30%, 26%, 22% or 18% of the calories from fat. Moderate fat restriction (26% fat) resulted in changes similar to the attempted 18% fat diet. Those who aggressively restricted their dietary fat intake incurred two worrisome changes:

* Higher triglycerides

* Reduction of the "good" HDL cholesterol

Therefore, the extra effort to severely restrict fat may be less beneficial and counterproductive.

What about the very low fat diets promoted by doctors Dean Ornish and Nathan Pritikin?

Yes, those diets have reduced heart disease--but the people simultaneously lost weight, consumed abundant fiber-rich foods (fruits, vegetables, legumes, beans, whole grains), meditated and exercised. This package seems to be the key to success --instead of the low fat diets with too many refined sugar foods and little to no weight loss.

What's an easy way to reduce dietary fat?

Please note that "low fat" differs from "no fat." A low fat diet with 20 to 30% of total calories from fat allows most active women to intake 40 to 60 grams of fat per day and most active men to intake 50 to 70 grams of fat per day. By choosing fewer fatty meats, greasy chips and added fats, you'll reduce your fat intake to a healthful level. This change can also create the calorie deficit needed to lose weight and enhance your heart's health. If you do not want to lose weight, add back calories--either with extra fruits, grains and low fat dairy or olive oil, nuts, peanut butter and other unsaturated fats.