I want to eat only apples for three days in the third grade. Is there a problem with losing weight like this?

The result is stomach trouble! I am an example. I want to eat three meals and gradually reduce it. Dinner is less than breakfast and Chinese food until I feel moderate and don't want to be hungry or gain weight. Just stick to it. But pay attention to quality, or it will be harmful to your health. Ensure the intake of nutrients. Now I think the weight loss effect is good.