A calorie is a calorie, no matter where it comes from. Most weight-loss diets help you to restrict calories in one way or another. Ideally the new routine gets you to eat less, eat healthier and exercise more. Seems simple, right? It is, in theory.

Your weight remains stable when you eat the same number of calories you use up. So, in theory, if you eat well and exercise - and in the process burn more calories than you consume - you lose weight.

But in practice it’s easy to run into roadblocks. Adopting healthy eating and exercise habits can be difficult. It takes time and effort to work physical activity into your daily routine. A good diet can be your road map to safe and effective weight management. Conversely, a poor diet can leave you spinning your wheels - or, even worse, pose serious health problems.

Components of an effective weight-loss program must include:

  * A healthy diet that helps you select, prepare and eat healthy foods.
  * An exercise plan that helps you increase your activity throughout the day as well as incorporate a more rigorous exercise period several times every week.

Weight-loss programs come in many forms today. Some prey on the desire for a quick fix, and some of these diets do help you lose weight quickly - at least for a while. But maintaining a healthy weight isn’t something that most people can manage quickly and maintain over the long haul. It’s a process, and it can be tough, but it’s not impossible. If you’re ready to commit to lifestyle changes - eating healthier and being more physically active - then you’re well on your way to achieving a healthier weight.
Weigh the facts - avoid the fads

The benefits of living at your healthy weight are numerous. You’ll look better and feel better, and you’ll probably live longer, too. But it’s important to find a program that’s safe and works effectively. Do some research before jumping into a new diet routine. If you have questions, talk to your doctor or nutritionist.

If you’re considering a new weight-loss plan, evaluate it by the following statements to see how the program holds up. If one or more of these apply, raise a red flag.

  * Promises of a quick fix
  * Dire warnings from a single product or regimen
  * Claims that sound too good to be true
  * Simplistic conclusions drawn from a complex study
  * Recommendations based on a single study
  * Dramatic statements that are refuted by reputable scientific organizations
  * Lists of “good” and “bad” foods
  * Advice given to help sell a product
  * Opinions based on studies published without peer review
  * Recommendations from studies that ignore differences among individuals or groups

Here, in alphabetical order, is a bird’s-eye view of some popular weight-loss plans - with a look at their premises, their founders or main backers, and what the scientific evidence shows. Take a look at each and use the list to figure out which are the healthiest programs to follow. Then talk with your doctor about a weight-loss program that’s right for you.

The list is divided into two categories - weight management programs and diets, an important distinction to make. A diet helps you decide what and how much to eat, while weight management programs often include physical activity and behavior change in addition to your dietary plan.
Weight management programs

  * Body-for-Life (Bill Phillips)

    Premise: A 12-week fitness plan in which you eat a high-protein diet and exercise regularly. Phillips, a bodybuilder and entrepreneur, emphasizes portions, not calorie counts. You eat six meals a day - each meal consisting of one portion of protein and one portion of carbohydrates - and add a vegetable to two of the meals. Once a week, you’re allowed a “cheat” day to splurge on your favorite foods.

    Facts: This program’s success is based on testimonials and anecdotal evidence. Although Body for Life emphasizes low-fat foods, the diet doesn’t consist of enough variety for a truly healthy diet to meet all of your nutritional needs.

  * Lifestyle Program (Dean Ornish, M.D.)

    Premise: Combines vegetarian and low-fat diets. Encourages high-fiber foods and limiting processed foods, such as cheese. Also recommends a daily exercise program. Dr. Ornish is the founder, president and director of the nonprofit Preventive Medicine Research Institute and has published numerous books about reversing heart disease through diet and exercise.

    Facts: There’s moderate evidence that cholesterol levels may decrease and that this diet is effective for weight loss. It combines - as all effective weight-loss programs do - a healthy eating plan with regular physical activity. There’s also good evidence that it can treat and possibly prevent heart disease, though some people have questioned its practicality. Many people can’t follow a 10-percent fat diet long-term.

  * Mayo Clinic Healthy Weight Pyramid (Donald Hensrud, M.D.)

    Premise: Studies show that both volume and weight of food play a role in feeling full. By choosing low-calorie energy-dense foods - large volume, large weight, but not many calories - you can still eat the same amount of food you’re accustomed to eating and be full on fewer calories.

    Facts: When you consume more foods that are low in energy density, it actually becomes more difficult to consume large amounts of calories. This promotes weight loss. Coupled with improved activity habits and behavior change, this approach focuses on improving health - and weight - over the long-term. This program emphasizes foods that are low in energy density: fruits and vegetables and healthier choices within each of the five food groups. Daily physical activity is emphasized for its role in both managing weight and improving health.