Have You Heard of the 80 / 20 Rule?
Calories do not matter because calories in do not equal the calories out. You will be on a yoyo diet which will leave the individual on a diet feeling that he is a failure and very insecure.
Bio-individuality what works for one does not necessary mean that it will work for the other.
What is important to take note of is the 20/80 rule where 20 % should be comprising of exercise and the other 80 % should be the quality of food you eat. This is where the true results come from.
If your diet consists of a lot of processed food then your body converts it to sugar, your insulin goes up to neutralize it so your blood sugar drops. That makes you hungry again. You feel miserable and you eat again. More sugar and processed food and the yo yo begins. You start to put on weight because the body does not know what to do with this unhealthy food and stores it in your fat cells. As a result your weight goes up.