They essentially add vitamins and things,which isn't necessary with a good diet.Not sure what the ingredients are but not having an ingredients list is very risky considering there is absolutely no guarantee that they may contain unsafe things or unhealthy things
If you have the ingredients on the packaging it might help to understand,but I don't like unclear labeling personally like when companies say "vegetables" and things like that without verifying which ones they are since you have no idea what may be in them.