There is no better way to sort through the vast array of weight loss programs than with a long term medical study. They are the best sources of unbiased information on diet plans. Not all of the popular diets have been subjected to long-term clinical studies. In fact, most have not. However, there is solid research for the Atkins Diet, Weight Watchers, Rosemary Conley Eat Yourself Slim or Slim-Fast.
Most scientific studies show that the majority of mainstream diets will lead to short-term weight loss -- as long as you stick with them. A University of Surrey study published in Public Health Nutrition in 2009 followed 300 overweight or obese participants who were using the most popular diet plans. Over the course of six months, all the participants lost a similar amount of weight (from 11 to 19 lbs), regardless of the diet they followed. This confirms what diet experts have long suspected -- weight loss is a simple formula of calories in vs. calories out, so any diet that reduces calories will help you shed pounds. Exercise is also essential to keeping the weight off. The tricky part is following the diet until you get to your goal weight. That's why finding a diet you can stick with is so important. Dieters who engage in long-term support, either in person or online, have a better chance of maintaining their weight loss than those who do not. While websites like eDiets.com have features that provide support, Weight Watchers is king when it comes to face-to-face meetings, and clinical studies show that in-person meetings trump Internet-based support when it comes to initiating and maintaining weight loss. In research studies, Weight Watchers easily gets the best ratings for long-term success. That's not because its overall plan is significantly better or worse than others. Rather, Weight Watchers' foundation for group meetings and support leads to a far lower dropout rate, and its flexible eating plan allows participants to eat what they like in moderation. In repeated studies, participants were able to stick with Weight Watchers for a longer period of time.
The Atkins Diet is opposed by the American Medical Association, the National Academy of Sciences, the American Cancer Society, the American Heart Association and the National Institutes of Health. This is mainly because the Atkins Diet plan is far outside the realm of traditional dietary advice, and the long-term effects of a high-fat diet on cardiac health are still unknown. Plenty of experts now say that low-carb diets are safe, at least in the short term, except for people with kidney problems. In the long term, low-carb dieters, like adherents of other weight-loss programs, are just as likely to lose weight if they stick to their diet, and also just as likely to gain it back when they stop the plan. All of the medical studies concluded with the same advice: the best diet is one that you can stick to.
Diet pills are generally found to be ineffective.
~ The New England Journal of Medicine