The only things I know about supplements come from what we give our horses at the barn. But I think what I will tell you can apply to people as well. We order supplements based on the needs of each individual horse. This means that not all the horses get the same kind of supplements, or sometimes not even the same amounts if they are getting the same things. Some horses need supplements to make them look better: be it for their coats, manes and tails, or for weight control. Others need things for their health such as vitamins they, for some reason, have a hard time getting from what we feed them regularly. So take this into consideration, what may be right for one horse, will most likely be entirely wrong and possibly even unhealthy for the one the next stall over.