It's a common problem these days: obesity. I have even seen some children as young as ten who are obese. It's really quite sad, but I believe that obesity is caused by a lot of factors, such as the genes and the person's lifestyle (diet and exercise). I'm no expert, it's just what I have read in some of the articles. Of course, there could be other causes, like an underlying disease, or something. Lots of factors, but the most obvious one would be the diet. For me, anyway. :)
Some people have tried dieting and it never worked for them. I believe it's because they were not able to sustain it after losing a couple or so of pounds. You can accomplish weight loss success with the best diet plans, but equally important must be the discipline to stay on it!
I have a very good friend who tried those different diets, and she did manage to lose some significant pounds off her weight. Sad thing though, is that after losing those pounds she went back to her usual lifestyle again! She's trying to lose weight again, and so I have told her about this site, Weight-Loss-Diet-Help.com, where she can choose from the different diets that would suit her best. I have found some really good sites there, like Medifast, Weight Watchers, South Beach Diet, and more.
Last I heard from her was that she did visit the site and plans to start with another program again. I really do hope that she'll stick with it this time; I'm hopeful. :)