There are essentially three different types of diet pills on the market:



Appetite Suppressants - Drugs of this class are frequently stimulants of the phenethylamine family, related to amphetamine (speed).

Fat Burners - Drugs of this type may help increase the body's metabolism and increase the burning of fat.

Fat Binders or Blockers - This type of drug reduces the amount of fat molecules that pass through the intestinal lining.

Appetite Suppressants

This class of drugs is designed to appeal to people who believe that the cause of their weight problem is too much hunger. Certain stimulants (which are sometimes addictive) will reduce the individual's interest in food - at least temporarily.

Many people turn to this type of medication to lose weight, because they believe they eat almost compulsively. The drugs promise to reduce the feeling that food is needed, thereby suppressing the psychological motivation for eating.

Studies show that appetite suppressant medications work best when combined with a weight-management program that helps you improve your eating and physical activity habits. It has also been shown that most people regain the weight they lose when they stop taking the appetite suppressant medication.

Fat Burners

Both appetite suppressants and fat burners help to regulate the appetite by acting on the hypothalamus, a part of the brain.

Fat burners also release chemicals into the brain that increase the stress response, which is sometimes known as the "fight or flight" mechanism. When this stress response is triggered, the body will burn more calories to ready itself for the perceived "danger," even though the body remains at rest.

This type of product is sometimes sold as "thermogenic weight loss formulas". Fat burners containing ephedra (a chemical very similar to methamphetamine, an illegal recreational drug) were among the first to become popular, but they were banned by the FDA due to the high rate of serious side effects and related deaths in 2004.

Fat Binders

Fat binders work by "binding" the fats in the stomach and intestines, preventing the body from fully digesting and absorbing them into the bloodstream. Naturally, this type of pill will only assist a patient to lose weight if the diet is high in fats. Some claims have been made that fat binders will also help lower cholesterol levels, but this has not been proven.

Fat binders appeal to the public because of the perceived promise that weight can be lost without a change in diet. When taking the drugs, a patient should be closely monitored by a doctor to make sure that they are absorbing enough of the fat-soluble vitamins A, D, E and K.

All diet pills prescribed by a physician, whether appetite suppressant, fat burner, or fat binder, are meant to be used by people who are morbidly obese, or who have health problems that can be made more critical by being overweight.

They are not intended for the folks who need to lose a few pounds to get into a nice pair of jeans, and few reputable doctors will prescribe them for this purpose. However, most health insurance companies will not cover weight loss drugs because of fraudulent "weight loss centers" that pushed addictive amphetamines in the 70's and 80's.

All patients using any of these drugs should be closely monitored for any possible side effects, and should also receive nutritional counseling and education so they don't regain their weight once they stop taking the drugs.

Although many supplements and diet pills are also available over-the-counter, without a prescription, people should be very cautious about using them without getting a good physical checkup, and without talking to their doctor first. A drug that is safe for one person may not be safe for another, because underlying health conditions can be made worse if the wrong drugs are taken.

Appetite suppressants containing stimulants like caffeine have been known to raise the blood pressure and heart rate, an increased risk for anyone with heart disease. Fat blockers can cause intestinal disturbances like flatulence and diarrhea, as well as causing nutritional imbalances. And some diet pills can become addictive.

Regardless of the type of diet pill a person uses, they are not a substitute for a healthy diet and an increase in healthy exercise. Without permanent changes in diet and lifestyle, most people regain their weight as soon as they stop using the drugs.