Vitamins or dietary supplements will not decrease the size of your penis. But supplements of any kind should never be taken without first consulting a health care professional. Many supplements that are now available for body building and sculpting have dangerous side effects. So it is important to get good medical advice and be careful.

^ Taken from a website(better safe then sorry) of health experts. Hopefully, what I'm getting doesn't have the side effect of dick shrinkage. But I was told by a reliable workout source those particular supplements wouldn't be anything bad.