(HealthDay News) -- Fad diets are weight-loss plans that promise quick, dramatic weight loss.

Fad diets rarely help with long-term weight loss, and can even be dangerous to your health, the American Academy of Family Physicians says.

Here are the AAFP's suggestions for how to recognize a diet that promises more than it delivers:

• Diets that promise to help you lose more than one to two pounds a week.
• Diets that promise weight loss without a healthy diet low in fatty foods.
• Diets that base claims on "before and after" photos that show dramatic weight loss.
• Diets that pitch testimonials from users or so-called experts.
• Diets that focus on only one type of food, and don't encourage a healthy, balanced diet.
• Diets that require you to spend a lot of money on pills, seminars or prepared foods.