How many of you use a vitamin c serum?

It IS cheap and only lasts about 4 months before it oxidizes. Keep it in a cool dark place. It is a basic formula, if you are paying for an expensive brand, you are wasting your money. You can even buy and make yourself to save lots of bucks, but I'm just not that talented. You can buy it on amazon for $24 and it is special made upon order. It makes my skin even, and complexion sort of "glow" and it helps a tiny bit with my acne.
 
More4Me said:
I was told that the only way vitamin c can be potent to the skin is for it to be ingested (internal). External (topical) use has no effect.

I heard this also, that applying it to the skin had no affect!