There is no specific time for this, is there? Everyone's physique is different. Some people will exercise and pay attention to their diet, which may be more effective. Or it may not be obvious that some people are not fat and want to be thinner, but the fatter they are, the more obvious they may be. Generally, the side effects of instant products are relatively large, so it is suggested to combine exercise with reasonable diet. Not bad. My friends are using it, too.