Eating only one meal for dinner is good for losing weight. You must eat three meals until you are full. If you only eat one meal, you will not lose weight, but also have other problems, such as gastrointestinal problems and insufficient energy supply to your brain. If you have no energy all day, you can actually eat some fruit after dinner. Eat more vegetarian food. You can eat more lunch, eat less dinner, and don't eat or drink water for an hour before going to bed.