Weight gain through fat calories:
In scientific studies, researchers have found that in a high-fat diet, some individuals gain weight as expected, while others seem resistant to fat calories and maintain their weight. Upon deeper investigation, genes were identified as responsible for blocking excessive fat uptake from food. When these genes work effectively, they prevent the body from absorbing excessive fat, and the calories end up in the toilet. Individuals with genetic defects in these genes react differently. The fat-uptake protection is lost, and the body absorbs all available fat, resulting in weight gain.

Weight gain through carbohydrate calories:
Similar to fat calories, carbohydrates do not affect everyone in the same way. Some people seem to gain weight through excessive carbs, while others are resistant to them. Again, scientific studies have identified genes involved in this process.

Weight loss through exercise:
Studies with a large group of participants following the same exercise program over several months have observed an interesting effect: participants can be classified into two groups, responders and non-responders. Non-responders appear to lose between 3 and 6 times less weight through the same exercise program than responders, and the genes responsible for this effect were identified.

Weight loss through calorie reduction:
Also, eating fewer calories appears to affect people differently, and genes seem to be the ones to blame. While some people lose weight quickly, less genetically fortunate individuals lose 3 times less weight with the same reduction in calories.