If you know anything about physiology and psychology this really isn't surprising. Firstly, low calorie diets put your body into a starvation mode. You are eating so little that the body has to take emergency action in order to protect itself - it thus slows down your metabolism to reflect the reduction in calories, eats into your muscles to feed itself, and begins storing fat rather than burning it.
This is natural self-preservation - the body always works for its own survival, in this case acting to ensure that the brain and vital organs get sufficient calories to continue functioning.
While this is happening, your mind is also under stress. Most diets are very restrictive, requiring immense sacrifice and will power to stick to them. When eventually you crack and give up, your body is burning fewer calories per day than when you started, so as soon as you return to your pre-diet eating patterns, you will gain even more weight.
What can you do?
So if dieting doesn't work, what does? No surprises here - the researchers noted that "exercise may well be the key factor leading to sustained weight loss. Studies consistently find that people who reported the most exercise also had the most weight loss."
So if you want to lose weight, the recipe is simple - exercise appropriately, and base your diet around lean protein, fresh fruit and vegetables, and whole grains.
Your weight loss won't be instant, but it will be sustained, and it will be healthy.