One easy word to explain that : Willpower ! They have no willpower to stop eating junk and learn to exercise and eat properly or they haven't had a good lifestyle where they learned to eat properly. There is also Hypothyroidism that makes you gain a lot of weight. I have that but due to other medical problems and lot's of exercise, I lost all of it. No willpower to want to be normal weight. Junk food is just too easy to get and eat. You have to want to lose weight!
Why do fat people complain about their weight but do nothing about it? They just keep on eating bad foods and drinks.
The first answer is basically it. You have want to lose weight otherwise it won't work and you also have to have determination and motivation. My sister's friend wanted to lose weight but she kept eating junk food and it got nowhere -so now my sister is doing diets and exercise with her. And she is getting somewhere now
It's not what eat that makes you fat it's how much you eat. If a person sits there and eats all day sure it's going to be bad and you will gain weight.
Hmmm I kind of agree with the willpower, but of course it's not that easy. Rooster already mention hyperthyroidism. Some people blame low metabolism. I got really depressed for a while blaming myself for not having willpower. But it's what you chose in the beginning of the day to eat or not to eat. Skipping breakfast is bad because it makes you crave high calorie food. You need to satisfy your body with fruits, veggies, and low fat foods. Because when you get hungry, it gets really hard to make wise food decisions. Just think of the great Chinese famine. Starvation makes you do crazy things. I know this is on a lower scale, but when you don't have any more leftover carbohydrates stored on your body, it messes with your brain. So I don't really recommend restricting calories, just making healthier food choices.
With all the fast food around, it is super easy to eat more than we need. After my soccer game on Sunday I went to taco cabana and my meal was over 1000 calories. Almost half of what I needed that day. But because I'm used to eating large meals of fruit, I coulve eaten twice as much as I did at taco cabana. It's a good thing I wasn't paying or else I probably would have gotten more food. Those high fat meals don't satisfy your brain's need for carbohydrates. Fruit and rice are very good sources of carbohydrates.
Besides your body's need for carbohydrates, it also needs vitamins and minerals. Five servings of fruits and veggies a day is what is recommended. And if your body senses that you can get some vitamins from the fruit in Apple pie, you might start craving it. You just have to eat more fruits and vegetables, it will help a lot. If you only like one fruit, then that's all it takes. Just eat lots and lots. You can make sure you are getting all your nutrients on cronometer.com .