I suspect the concern may have to do with the amount of vitamins/minerals taken radomly in isolation. This should be made clear.

What is known is that antioxidants demolish free radicals. Vitamin C eg demolishes the free radicals that caus inflammation. However when an antioxidant nutralizes a free radical it becomes itself a free radical. If you consume a range of antioxidants you have more of a balance so thaa cycle so to speak is set up . The best way to do this is with food as food has unique combinations of nutrients which often work synergistically (that is the benefit together is greater than the sum of its parts).
If you are unable to manage a very nutritious diiet, I think a wise way to go is to seek advice and not just choose random supplements. This is just my thoughts. Personall I've developed an "eat smart" plan to help me with symptoms of CRPS/RSD.
jeisea
http://www.crps-rsd-a-better-life.blogspot.com