If you've tried every calorie-restricting diet out there but still can't keep the weight off, there's a reason: Diets don't work.

Over time, the majority of dieters regain any weight they may have lost, according to researchers who pored over a slew of diet studies recently. So instead of counting calories . . .

Eat for Good Health
The concept that you can permanently shrink yourself by temporarily eating less is mostly bunk -- for most of us. In fact, the health benefits of short-term weight loss still need to be closely examined. Instead, your goal should be to eat nutritious foods that make you younger -- and make that a lifelong habit. The good news? Your waist may shrink as a fringe benefit.

Getting Started
Kick-start your lifelong healthy-eating habits with these tips:

• Focus on your waist, not your weight. (Learn why your waist size is key to a younger RealAge.)
• Eat three main meals, plus snacks, so you're never hungry. (Sign on to use this online meal planner and shopping-list generator.)
• Don't buy anything with more than 4 grams of saturated fat or 4 grams of any sugar (especially high-fructose corn syrup) per serving.
• Strive for a rainbow of colors in your meals. Here's how to do that.
• Eat a little healthy fat -- like a handful of walnuts -- about 20 minutes before a meal. It will take the edge off, so you won't be tempted to overeat. (Here are some good pre-meal options.)
• Eat a fiber-rich breakfast every day. (Check out RealAge's picks for the best morning meals.)
• Walk every day for 30 minutes. (Compare your walking successes with an online fitness buddy.)

Get more tried-and-true waist-management strategies from RealAge experts Michael Roizen, MD, and Mehmet Oz, MD.