Also, diets don't work. People can lose quite a lot of weight but for the overwhelming majority, it will go back on again. Maybe not straight away, but the recidivism rate is HUGE, there is no diet that has a very good evidence base etc and it is believed that a body that has been starving lays down (and holds onto) fat faster following a prolonged low calorie diet because it assumes once the caloric intake goes up that it is "feast" time to prepare for the next famine, if that makes sense?
The irony is that most fat people will have spent FAR MORE time in their life eating a low calorie diet than naturally thin people, yet many look and say "oh, they just lack willpower", "they need to just DO IT", "it's simple" etc. The research evidence, however, is crystal clear that it is not easy and not a simple equation of reducing caloric intake.
I grew up in a house of obese people and I have seen it in action. They starve and starve for months, shift a few pounds or even stone and then it all piles back again. Plus more. I am about 7lbs overweight since having my baby but I am like a string bean in comparison to my family and believe me, starving yourself is a recipe for laying down TONS of weight. The worst regain always happened after radical diets e.g. Cabbage Soup and other very low calorie diets.
I never dieted before I was in my early twenties and then I did to lose some cosmetic pounds (to go from, say, a BMI of 22.5 to a BMI of 20). Worst mistake I ever made, it reset my natural "resting" weight to about a BMI of 24.
I am seriously thinking about giving up dieting because I really think, long term, starving yourself leads to WEIGHT GAIN vs weight loss. And misery.