I remember a recent study that claims skin exposure to the sun is necessary/needed to burn fat. I'll try to find it and update this comment. Edit: this seems t

I remember a recent study that claims skin exposure to the sun is necessary/needed to burn fat. I'll try to find it and update this comment. Edit: this seems to be the study https://www.nature.com/articles/s41598-017-16689-4 https://www.nature.com/articles/s41598-017-16689-4 The gist of it is that sunlight shrinks fat cells, but I might be oversimplifying it