He learnt from experimenting on his own life that moderation is the key to a balanced diet. No given diet is absolutely harmful but diets with very high carbohydrate and fat content should be restricted to minimum. In the end the total amount of calories taken in should be carefully watched. If a high calorie meal is consumed then one should compensatorily restrict calories at other meals. In the end to protect future generations there needs to be some control both at the consumer level as well as availability.