If you buy her a lot of apples, eat them, because apples are rich in nutrition and can basically meet people's needs. Of course, eat some vegetables every day to supplement the sodium in the body. Let her see how effective it is to lose weight in a week or two. It should work. Because a star lost weight in this way, I forgot which star it was. I read it in a hospital magazine, haha.
I hope it will help your girlfriend's plan. ...