Safety Issues Of Low-fat Diets

For much of the last half of the 20th century, the medical establishment recommended low-fat diets as a prudent way to lower the risk of heart disease and weight problems. In the early 21st century, researchers began to appreciate the distinction between fats that promote health and fats that undermine it. It turned out that indiscriminately low-fat diets were not effective and might even be harmful. Dr. Steven Nissen, vice chairman of cardiology at the Cleveland Clinic, told ABC news that, "Extremes of diet don't seem to be particularly healthy." He also warned against "subscribing to ultra low-fat fad diets".

Good Fats and Bad Fats

The Harvard School of Public Health points out total dietary fat levels are not linked to disease or even to body weight. It is the type of fat in the diet that makes a difference. Trans fats and saturated fats are considered "bad" fats. They have been linked to heart disease, for instance. Monounsaturated and polyunsaturated fats are considered "good" fats. They help protect against heart disease.

Some Fats Are Necessary for Good Health

If a low-fat diet results in too little intake of "good" fat, it could negatively affect your health in many ways because fat is a vital nutrient. Hormone levels and immune responses depend on substances derived from fat. Seventy percent of the brain is fat; it insulates nerve fibers. Cell membranes could not enclose cells without fat. Interfering with fat in any of these systems could result in deficiencies that could weaken your body. According to Family Education, unwisely restricting healthy dietary fat can induce hormone imbalances in women, cause fertility problems and result in dry skin and hair.

Poor Food Choices On Low-Fat Diets

Dieters following a low-fat diet may be tempted to compensate for their lower fat intake by eating significant amounts of processed foods labeled "Fat Free" or "Low Fat." The ingredients listed on the nutritional labels of these products in many cases reveal high levels of sugar in its various forms and additives. Furthermore, avoiding some foods because they contain fat could result in protein deficiency.

Special Needs

Writing in the March 2007 American Heart Association's journal "Circulation," Alice H. Lichtenstein and her colleagues note that, "...some population subgroups, such as growing children, pregnant women, lactating women, and the elderly, have special needs for essential fatty acids and caloric density." Poorly designed, very low-fat diets are unlikely to meet these needs.

Depressing News

Low fat diets may even make you a bit more angry and hostile than normal. A small study involving 20 men and 20 women published in the British Journal of Nutrition in March, 2007, concluded that, "...a change in dietary fat content from 41 to 25% energy may have adverse effects on mood" according to anger-hostility ratings taken one month after the change in diet.