First of all, you can hint at her with a topic. For example, if you see a group of people in the street, you can say that they are fat. You can tell your wife that those fat people are really ugly. Then I think he will notice that she may imagine her weight problem. I think she will know whether he is fat or not. Since you said so, she shouldn't directly say that you are calling her fat. ?
I think your wife will know herself, too. She won't even notice. If she asks you at this time, do you think she looks fat? At this time, you should answer skillfully. If you want to be vague, you can say that she has become fat now, and you can say that she may be fat. ?
Not bad. You can ask her to weigh it. Women don't like being fat either. When she finds herself fat, she will naturally lose weight. This is one of the ways. ?
Another way is that you can dig up your old photos, but she was still very thin. When she comes, you should pretend to look at the photos and ask her to come and have a look. ?
At this time, you can also pretend to mention her previous figure. When she sees her former self, she may think of her present self, and she should realize it herself. ?
Generally speaking, girls should try to lose weight when they find themselves fat. At this time, you gently told your wife to lose weight, and your goal was achieved. ?