Review: OST C20 Original Pure Vitamin C20 Serum

Review OST C20 Original Pure Vitamin C20 Serum

I was very much in two minds as to whether I was going to post up my review — bloggers (and Redditors on the Asianbeauty subreddit) give it such unanimous praise that any negative review would garner total outrage I feel. I also didn’t actually intent to write anything about it, so please excuse the lack of ingredients and photos (just Google for them). I tend to abandon products that don’t quite agree with me quickly; they get passed on to friends or my mum, or they go straight to the bin. I think life is too short to struggle along with a sunscreen that leaves the skin sticky or a serum that smells of meat.

I don’t have any strong dislike for the OST C20 Original Pure Vitamin C20 Serum, just “meh”. This serum from Korea has been formulated to brighten, refine, and even skin tone using 20% vitamin C (ascorbic acid). Once the bottle has been opened (lid replaced with pipette) it must be stored in the fridge to keep the serum stable and effective. Company says its shelf life is a year and once it has been opened, it should be finished within 12 months.

The serum is light and non-greasy, but it has a sticky finish. You can feel it on the surface even after half an hour or so. It doesn’t bother me — any products I apply after take away the stickiness. This smells strongly of oranges. Orange scent in vitamin C serums is quite a cliché for me to the point that I really do not enjoy the smell of it. It doesn’t help a lot of household cleansers also have the same scent. But it’s not at all unpleasant. The serum feels like the skin care equivalent of a pep-up shot of coffee. There is a slight tingling upon application and a tightening feeling. Nothing uncomfortable. I don’t really have dark patches to fade, but after applying a generous amount morning and night for just short of 3 weeks, skin looks fresher, brighter, and somehow paler (even though I have no tan to fade).

My major gripe with the serum is that it is not stabilised. While ascorbic acid is a potent antioxidant, it is highly unstable. It breaks down upon exposure to air and light, slowing turning it dark amber (in other words, no longer fresh and not very effective). The colour of ascorbic acid serum should be clear up to a dark champagne — my C20 Serum was already slightly yellow when I first opened the bottle despite that it was manufactured just a month ago! After having it for 3 weeks, it changed to orange. The production and expiration dates printed on the bottom of the bottle seem absolutely arbitrary. Is it me, or does that seems awfully short lifespan even for ascorbic acid serum? My Melano CC Intensive Anti-Spot Essence (also uses the same form of vitamin C) is still crystal clear after a few months with no sign of it oxidising. The Paula’s Choice Resist C15 Super Booster trial size bottle I have is still fine after a few weeks.

I probably wouldn’t buy the OST C20 Original Pure Vitamin C20 Serum, despite it being effective, but that doesn’t mean that I didn’t like it. It just didn’t impress me enough to rush online and re-order when there is a half a bottle of oxidised serum sitting in the bin. This mad dash against time to finish the serum before it changes just isn’t worth it when there’re a myriad of other better formulated vitamin C serums in the market. “Meh.”

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