Effective is effective, but most of them are controlled by themselves. Work and rest normally during use, and don't stay up late or anything. You must have breakfast. Breakfast should be 90% full, lunch 70% full and dinner 50% full. Once you eat too much, overeating will not decrease, but will increase. If you are a foodie, it may be difficult, but if you can survive these three months, the rest of your life will be great. Under normal circumstances, it won't rebound unless you overeat as soon as you use it. There are no side effects and no harm, because it is mainly for conditioning the body. The first box is for conditioning and the second box is for slimming. If your body is still healthy, you will lose weight in the first box of conditioning period. If you are too weak, you will be unlucky. You may have to rest until the third box.