The conventional wisdom is that we gain weight by eating too much and moving too little. There is very little truth in that statement. Obesity is not the result of calories in versus calories out, it depends on how much time we spend storing fat compared with the time we spend burning fat.
The body has the option of fat storing and fat burning. When we eat carbohydrates, the majority are converted into sugar which is absorbed into the blood stream. Under the influence of the hormone insulin, sugar is stored as fat until all the excess is removed from the blood stream.
If we then refrain from eating, insulin switches off and the body starts burning the fat as fuel.
If, on the other hand, we eat more carbs, maybe just a snack between meals, the body immediately switches back into fat storing mode.
For most of us on a conventional western diet, we spend most of our time storing fat and little or no time burning fat.
Storing more fat than we burn is what makes us fat. The solution lies with dealing with the root cause of the problem.