A final important consideration when it comes to supplementation is the psychological influence of the supplement. Some people feel that taking a supplement helps them to perform better. The placebo effect is when a person's belief that something has an effect results in a real physical change. For example, when someone gets confidence from taking a supplement, even if there is no proof of that supplement's impact, discontinuing use of the supplement may have a powerful effect on the person's state of mind. It may, in fact, be detrimental to his or her physical performance. In cases such as these, the continuation of the supplement is fine as long as it poses no serious health threat to the taker.