The real cause of obesity is an abundance of sugars, grains and other high carbohydrate foods. These are converted to sugars in the body.
A diet high in cheap, starchy, sugary, processed foods is the quickest way to become obese.
Eating too many carbohydrates causes your insulin levels to rise, sending your body a hormonal message telling it to store fat, while holding on to the fat that is already there. So not only will excess carbohydrates make you fat, they will also make you stay fat. Limiting sugar, grains and other high-carb foods is crucial to moderating this insulin response.
Eighty percent of your ability to reduce excess body fat is determined by what you eat. The other twenty percent depends on proper exercise, lifestyle habits and genetic factors.