Fat - is it friend or foe to the active individual? In the past, fat has been demonized by nutritionists and health care professionals alike because of its link to an increased risk for chronic disease. A high-fat diet (more than 70% of total caloric intake) does not bode well for the competitive athlete and the American College of Sports Medicine (ACSM), along with the American Dietetic Association (ADA) and Dietitians of Canada (DC), in their Joint Position Stand on Nutrition and Athletic Performance, recommend against it. But, a certain amount of fat, and from the right source, is necessary for proper functioning of your body, whether you are physically active or not. The ACSM, ADA, and DC state in their joint position stand that consuming less than 20% of your total caloric intake from fat does not enhance athletic performance. Fat should be a part of a healthy, well-balanced diet.

Why do you need fat in your diet?

• Fat is a constituent of cell membranes.
• Fat is needed in the production of hormones, such as testosterone and estrogen.
• Fat is needed for the storage of the fat-soluble vitamins, A, D, E, and K.
• It is a source of essential fatty-acids.
• It is a source of energy/fuel for your body.

What are the different types of fat?

• Saturated fats are fatty acids whose carbon atoms are saturated with hydrogen atoms. Saturated fats are typically solid at room temperature (lard, butter, etc.,). They can be categorized as long- or medium-chain saturated fats and are metabolized differently by your body. Long-chain saturated fats, found in foods such as bacon, are linked with higher LDL ("bad" cholesterol) levels. Medium-chain saturated fats, such as found in coconut oil, are metabolized by the liver to provide energy for the body and are not linked with increased LDL values. They are associated with health-promoting characteristics, such as protection against heart disease and aiding in weight loss. Some even purport that medium-chain saturated fatty acids may improve athletic performance because of the means by which they are metabolized by your body. Food sources of medium-chain saturated fats should be chosen over those with long-chain saturated fatty acids.
• Monounsaturated fats are fatty acids that have one carbon molecule that isn't bound to hydrogen. They are typically liquid at room temperature and when refrigerated, start to solidify. Olive and canola oils are examples of monounsaturated fats. When the diet is low in saturated fat, monounsaturated fats can decrease your risk for cardiovascular disease and lower your LDL levels.
• Polyunsaturated fats are fatty acids that have more than one carbon molecule that are not bound to hydrogen. These fatty acids are liquid at room temperature and when refrigerated. They include such oils as sesame and sunflower. Polyunsaturated fats have been linked with improved cholesterol levels.
• Trans fats are unsaturated fats that have been altered by adding hydrogen atoms so that they remain solid at room temperature. These include your hydrogenated vegetable oils that are found in margarine. Trans fats raise both total and LDL cholesterol levels while lowering your HDL ("good" cholesterol) values.

How much fat should you consume per day?

• Total fat consumption should not exceed 20-35% of your total energy intake, which is dependent upon your age, activity level, and body weight goals. The American Heart Association (AHA) states that if you are overweight, you should not consume more than 30% of your total daily caloric intake from fat.
• The AHA recommends that your intake of saturated fats should not exceed 7 percent of your total daily caloric intake.
• The Dietary Guidelines for Americans recommends that intake of unsaturated fatty acids should comprise approximately 10% each from monounsaturated and polyunsaturated sources of your total daily energy intake.
• Consumption of trans fats is strongly discouraged and should not exceed more than 1% of your total daily calories.

Healthy sources of fat:

• Olive, soybean, canola, sunflower, and coconut oils
• Lean cuts of meat
• Fish, such as salmon and tuna
• Seeds, such as sunflower and flaxseed
• Nuts, such as almonds

Sensibly including fat in your diet can help you to achieve optimal health. Diets extremely low in fat have been linked to depression, nutrient deficiencies, low energy levels, poor concentration, and even weight gain. Fat can be the active individual's friend when consumed from healthy sources and in the right proportions.

Resources:

American Heart Association

Food for Fitness, Eat Right to Train Right, 2004, Carmichael, C.

The Encyclopedia of Healing Foods, 2005, Murray, M.

OnFitness, November/December 2009, pp.68-69, "Fat Science."

Joint Position Statement Nutrition and Athletic Performance, The American College of Sports Medicine, The American Dietetic Association, and Dietitians of Canada