Whenever I see skin products advertising all of the vitamins they contain and the hair and skin benefits, I think to myself, "yeah, but how much do they help you if you wear them. Don't you need to eat them?"
I decided to do some research online to see if there was any scientific evidence that showed that vitamins could benefit your skin when applied topically. I was surprised when I actually found out that the basis for adding vitamin C to skin care products was a Duke study that had found a reduction in sun spots on the backs of hairless pigs with application of vitamin C.
So to get great skin we need to not only get enough vitamins in our diet, but we can also benefit from vitamins in our skin care products. Vitamins are very tricky though. Many vitamins are light sensitive and easily oxidized with exposure to air. Look for opaque packaging and for a container that minimizes the product's exposure to air. I have heard many people criticize anti-aging creams that are in twist top jars. The product may be potent with the first few uses, but with repeated exposure to air, becomes less effective.