Supplements For A Diet Program

Diet supplements are part of a broader class of nutritional products designed to promote weight loss. Supplements have gained mass popularity as concerns mount regarding the health risks associated with excess weight, but there is little evidence diet supplements taken without an accompanying balanced diet and regular exercise program will be effective long term. Diet supplements are divided into two categories -- lipase inhibitors and appetite suppressants. Lipase is the human enzyme that breaks down dietary fats in the intestine to permit their absorption into the body. Five supplements are prominent in the nutritional products market.

Orlistat

Orlistat is a lipase inhibiting chemical compound that prevents approximately one-third of dietary fats from entering the body; the fats that are not broken down are passed through the intestines and eliminated. Orlistat is marketed as Alli (non-prescription formulation) and Xenical (prescription). It is approved for use as a diet supplement by the U.S. Food and Drug Administration. Orlistat is an effective supplement for morbidly obese persons (Body Mass Index over 30) who have experienced difficulty losing weight through diet and physical exercise alone.

Sibutramine

Sibutramine is an appetite suppressant sold as the prescription medication Meridia. Approved by the FDA, sibutramine is a chemical that suppresses activity in the hypothalamus, the brain region responsible for appetite control. Sibutramine encourages the hypothalamus to simulate a feeling of greater stomach fullness immediately after eating, thereby reducing the patient's desire to eat more. Sibutramine is most effective as a component of a weight loss program that includes a healthy balanced diet and regular physical exercise. It is not recommended for persons with a history of cardiovascular disease.

Hoodia

Hoodia gordonii is a spiny, leafless plant species that grows naturally in arid regions of southern Africa. A succulent, hoodia has a reputation among indigenous Africans as an appetite suppressant. In recent years, hoodia extract attracted worldwide attention as a commercial diet supplement. Despite intensive testing and research, there is little credible scientific evidence that hoodia has any long-term effect on appetite suppression or weight loss.

Caffeine

Caffeine is a central nervous stimulant found in many modern foods and beverages. There is some scientific evidence that caffeine supplements suppress appetite, promote greater utilization of stored body fat as energy and stimulate thermogenesis, the chemical process through which the body produces heat when food is digested. For these reasons, caffeine may contribute to short-term weight loss; it is not a proven long-term diet supplement. Caffeine is also a diuretic, promoting increased urine production that may temporarily reduce body weight through fluid loss. The side effects associated with caffeine consumption (irritability, poor sleep and anxiety) also make it a poor supplement choice.

Carnitine

Carnitine is an endogenous chemical (originating in the human body) produced in the liver from amino acids lysine and methionine. Carnitine transports essential fatty acids used to generate human energy from the bloodstream into the mitochondria, the "engine room" that powers every human cell. Like many popular diet supplements, carnitine enjoys commercial appeal without the support of any significant evidence that it is an effective diet supplement. Carnitine has no known side effects.