It's estimated than more than 54 million Americans are on a diet. In the search for "a magic bullet" that will help them lose weight quickly and effortlessly, many try various fad diets. But do they work?

The experts say no. They are a short-term, quick-fix approach, and they don't work over the long term. They tend to overpromise results and they fail to deliver. Here are some tips for spotting fad diets:

• They claim or imply a large or quick weight loss of more than 1-2 pounds/week. (In fact, slow, gradual weight loss increases the chance of weight loss success and of keeping weight off over the long term.)
• Promote magical or miracle foods. (No foods can undo the long-term effects of overeating and not exercising or melt away fat.)
• Restrict or eliminate certain foods, recommend certain foods in large quantities, insist on eating specific food combinations, or offer rigid, inflexible menus.
• Imply that weight can be lost and maintained without exercise and other lifestyle changes.
• Rely heavily on undocumented case histories, testimonials, and anecdotes but have no scientific research to back claims.
• Contradict what most trusted health professional groups say, or make promises that sound too good to be true.

All of the experts agree that the best way to lose weight is a combination of restricted calories and increased physical activity, with a goal of slow but steady loss of 1 - 2 pounds a week.

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