They are ubiquitous and always "new" and "better" than the previous diet. The most recent craze is low-carb diets, in which one reduces carbohydrate and increases protein intake. However, carbohydrates, like protein and fat, are needed on a daily basis to maintain normal body functions.

Low-carb diet recommendations to decrease intake of donuts, white sugar, candy, regular pop, and white bread, which consist solely of simple carbohydrates, are healthful diet changes. But complex carbohydrates, such as whole wheat, rye breads, fruits and vegetables, wheat pasta, whole-grain cereals, and oatmeal are needed sources of fiber, nutrients, and energy. Moreover, low-carb diets may be contraindicated for persons with disabilities and certain health care conditions. For example, a wheelchair user who is at risk for osteoporosis from little or no weight-bearing activity is at greater risk by consuming a diet with restricted calcium intake (i.e., milk and yogurt). A low-carb diet may increase one's risk for heart disease and cancer, because of increased fat intake and decreased intake of fiber and complex-carbohydrate foods that help to lower cholesterol. It may also be contraindicated for someone with spina bifida, as a high protein diet could place excessive strain on the kidneys, as well as for someone with hypertension, because of stress on the vascular system.

A diet that includes a variety of fruits and vegetables, containing vital vitamins and minerals, will often assist in achieving desired weight loss because these foods replace more calorie-dense foods. Instead of eliminating foods from your diet, try adding 5 fruits and 5 vegetables a day.