size 0 concept and crash dieting?

I have been on a "diet" for years now. It's not seriously to lose pounds/lose weight but to become healthy. I try to eat less fatty foods, less junk foods, less sweets and more foods that are healthful to my body like vegetables, fruits and also the right portion of meat and carbohydrates. I also exercise often and have read a lot about diets. I know that crash dieting does not work. It is impossible to lose more than two pounds a week in a healthy way. Also, I know that diet isn't enough if you really want to lose weight, you have to exercise enough. Thanks for the response on my discussion!