Everyone knows the principle of calories in calories out. That’s not the issue. The issue is the huge array of factors - including economic, social, physiologic

Everyone knows the principle of calories in calories out. That’s not the issue. The issue is the huge array of factors - including economic, social, physiological (particularly hormonal) and emotional (particularly subconscious emotional) that influence the volume of calories in and out. If it was just a case of making conscious choices to consume fewer calories and expend more, there would not be the widespread problem there is. Clearly there is more to it, which is why people are downvoting you. You’re not making a point that everyone hasn’t heard before a thousand times.