When you say low upper body fat, you mainly mean the chest. If you are a girl, you must be disgusted with your small breasts. If you are a boy, it may mean that you don't have abdominal muscles and chest muscles.

If you just want to have breast enhancement like a girl, I suggest you don't eat some foods with high fat content, which will make you fat all over. Eating more papaya and foods with high vitamin A content will help breast enhancement and body shaping, and increase the beauty of curves.

If you are a boy, I feel that if your upper body is thin, your lower body is probably not much fatter. In my life, I have indeed seen many boys skinny and feel thinner than girls. If you want to eat something to gain weight, you'd better eat something that will gain weight all over your body. After all, the human body is a whole, and it is not entirely where you want to add it. Unless you go to a plastic surgery hospital for fat filling surgery, you can make up fat where you want to be fat.

Regardless of boys and girls, the best way is to eat reasonably, supplement all kinds of nutrients needed by the body, and then actively exercise to keep fit, which will naturally achieve the effect of body shaping. Take bodybuilders who take part in bodybuilding competitions as an example. They eat a lot at a meal, but because of the large amount of exercise, the body gradually grows strong muscles after absorbing a lot of nutrients.

So, in the end, I still want to advise you to face the laws of nature soberly. We are human beings and need to follow the methods of natural science to achieve effective and healthy body slimming and shaping. It will take some time, so don't rush or give up halfway.