Fat has been the most criticized food component of the last two decades. The message of many health care organizations has been the same - cut the fat. The justification for this recommendation was that excessive fat intake had been found to be associated with a number of medical conditions including heart disease, stroke, obesity, and cancer. This edict was so uniformly endorsed that many Americans thought that the secret to a long and healthy life was simply to cut fat from their diets.

However, during this time period the number of obese Americans increased dramatically. Currently the number of people in this country considered clinically obese, greater than 30% of their ideal body weight, ranges from 30-50%. Clearly, cutting dietary fat intake via the plethora of fat-free products did nothing to stem the tide of obesity in this country. In fact, in many ways, it may have contributed to the problem of obesity as well as other medical problems. Dr. Walter Willett (discussed in the heart disease section) stated that replacing saturated fat with carbohydrate can increase one's triglyceride levels and decrease the good HDL cholesterol, thereby increasing one's risk for heart disease. He states that healthy fats in the diet, such as monounsaturated and polyunsaturated fats can decrease the risk of heart disease, as well as help with obesity by increasing satiety.

Fat supplies essential fatty acids needed for healthy skin, hair, and digestion and absorption of fat-soluble vitamins (A,E,D,K). Fat can trigger you to feel full and stop eating. Fat provides 9 calories per gram. The recommendation for fat is between 20-35% of calories.

Different types of fats exist: saturated, trans fat, and unsaturated fats. Saturated fat is found in chicken skin, fat around meat, butter, and lard. Trans fat is found in hydrogenated products (unsaturated fats that have taken on a structure similar to saturated fats). Hydrogenation is a chemical process that snack food manufacturers often use to turn oils into shortening or stick margarine. Types of foods that contain trans fat include cookies, cakes, crackers, and other snack foods that can be found in any market or convenience store which do not require refrigeration. Increasing one's intake of saturated and/or trans fatty acids can significantly increase one's risk for heart disease.

The two major categories of unsaturated fat include polyunsaturated fat and monounsaturated fat. Polyunsaturated fats are found in most of the vegetable oils except for olive and canola oil, which are monounsaturated. Fish and fish oils are typically high in polyunsaturated fats. Polyunsaturated fats provide the body with omega-3-fatty acids, which are helpful in the prevention of heart disease. Monounsaturated fats are found in olive and canola oils and to a lesser degree peanut oils. In addition, avocados and most nuts and seeds are good sources of monounsaturated fats. Their use on a regular basis is associated with a lower risk of heart disease.

More Nutrition Topics