I knew a Doc who had a patient come in wondering how they got so fat because they were deathly afraid of food, eating only two slices of bread a day. The Doc was as confused too so he asked him if he drank any tea or coffee, to which he replied tea. The Doc asked him whether he had sugars or milk in his tea, to which he replied two sugars. The Doc asked him how much tea he drank a day, to which he replied 40 cups. This identified the issue very quickly
Another one, though I don't know this Doc at all had the same issue but with a guy who just ate loads and loads of satsumas. His line of thinking was that eating satsumas is good for you, so eating more = more good
Overeating will lead to being fat because it is overeating, by definition you are eating more than you use in physical activity so that excess will be stored as fat, sugary and fatty foods will get you faster yet there's not a food that if you overeat it you'll be good
Pls no one try sixty satsuma diet