Quack Diet Red Flags

Warning: Quick weight loss! No effort required!

By Jeanie Lerche Davis
WebMD Weight Loss Clinic - Feature

Reviewed By Brunilda Nazario, MD

Lose that weight -- you know you should. But the sheer numbers of weight loss programs sometimes confuse the issue.

The cabbage diet! The rice diet! The blood type diet! Atkins! South Beach! No carb! Low carb! There's even a Jesus diet (sans loaves and fishes).

"People who want to lose weight are a very vulnerable group because they're very frustrated," Kathleen Zelman, MPH, RD/LD, director of nutrition for the WebMD Weight Loss Clinic, tells WebMD. "Weight loss is hard, and everybody is looking for a silver bullet."

How can you discern which weight loss claims are true or false? Here's some advice from Zelman and from the Federal Trade Commission:

Does the diet promote rapid weight loss?

That's a clear signal it's unrealistic, says Zelman. When you start a diet, water weight is the first to go, she explains. If you lose much more than two pounds a week, you're drawing from both fat and muscles. That's not good, because muscle is one big factor that controls your metabolism. If you lose muscle mass, your metabolism will slow down. That's how the yo-yo cycle begins -- and that's one reason why some diets don't work, she explains.

"That's why we advocate losing weight slowly and gradually, so you're losing one to two pounds per week," Zelman says. "You're eating more food than diets allow, but you're tapping into stored fat more efficiently."