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Frequently Asked Questions About Weight Loss


7. What is weight cycling and is it harmful?

Weight cycling is the repeated loss and regain of body weight. When weight cycling is the result of dieting, it is called "yo-yo" dieting. A weight cycle can range from small weight losses and gains (5-10 lbs. per cycle) to large changes in weight (50 lbs. or more per cycle).

Some experts believe that weight cycling may be harmful to your health. Yo-yo dieters frequently regain fat instead of muscle which can slow down weight loss efforts in the future. Some believe that staying at one weight is better than weight cycling, even for those people who are obese. However, there is no convincing evidence to support these claims.

8. How do I spot a fad diet?

While there is no set approach to identifying a fad diet, many have the following characteristics.

  • Recommendations that promise quick weight loss.
  • Dire warnings of dangers from a single weight loss product or regimen.
  • Claims that sound too good to be true.
  • Simplistic conclusions drawn from a complex research study.
  • Recommendations based on a single study.
  • Dramatic statements that are refuted by reputable scientific organizations.
  • Lists of "good" and "bad" foods.
  • Recommendations made to help sell a weight loss product.
  • Recommendations based on studies published without review by other researchers.
  • Recommendations from studies that ignore differences among individuals or groups.
  • Eliminating one or more of the five food groups.

9. What prescription medicines are used to treat obesity?

Currently, most available weight-loss medications approved by the FDA are for short-term use, meaning a few weeks or months.

Most available weight-loss medications are "appetite suppressant" drugs. These weight loss drugs generally come in the form of tablets or extended-release capsules (pills that release medication over a long period of time). Appetite suppressants can be obtained by a doctor's prescription or purchased over-the-counter. One of the most well-known appetite suppressants is phentermine.

The long-term prescription drug Qsymia combines phentermine , the safer "phen" part of the infamously unsafe fen-phen diet drug combo. Phentermine is thought to suppress appetite by triggering release of the brain chemical norepinephrine. This suppresses the appetite by increasing blood concentrations of the appetite-regulating hormone leptin .

The other half of Qsymia is the seizure /migraine drug topiramate . Topiramate causes weight loss in several ways, including increasing feelings of fullness, making foods taste less appealing, and increasing calorie burning.

Another type of prescription weight loss drug is a fat absorption inhibitor. Xenical is the only example of this type of treatment approved for use in the U.S. Xenical works by blocking about 30% of dietary fat from being absorbed. Xenical is now sold over-the-counter as Alli.

Xenical is the only weight-loss drug approved for longer-term use in significantly obese people, although the safety and effectiveness have not been established for use of either medication beyond two years.

WebMD Medical Reference

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