The problem with diets is that they are only meant to be a weight loss programme. Often people who diet presume that once it is over they can go back to the way they were or they soon slip back into the bad habits that caused the weight problems in the first place.
Diets give you a starting point. After that, maintenance and moderation are the key. And if there is one thing we lack in our modern society it's moderation.
The problem with obesity the world over is that the food industry is huge. Its advertising is key to making us buy their products. It's a money spinning industry which has turned food from a necessary requirement for survival to a luxury, entertainment, a past time and ultimately to an addiction.
People eat for fun not to live and that is why the diet industry is so huge because people just can't stop eating and they think that a quick fix miracle is going to undo the problem.
If you want to lose a lot of weight, by all means try a diet, but think of it as a new lifestyle choice and combine it with other lifestyle choices that are going to benefit you. And don't assume that once you have hit your goal weight that you can just start eating again as before. You will probably spend the rest of your life watching what you eat, checking that everything is taken in moderation and avoiding certain foods.
This isn't necessarily a bad thing. Most of the food we eat is not necessary. Detaching the euphoria from the food you eat works for me. If you treat food as something you need to do to be healthy and alive you can start to moderate everything. But make sure you have fun in your life. If you use food as an escapism or a kick you need to address the rest of your life. Look at your fitness levels, your routine and address your life. Because that could be part of your key to success.