Skincare Review | OST Original Pure Vitamin C20 Serum
I was really excited to finally get my hands on a bottle of O.S.T. Vitamin C20 Serum. It’s been on my wish list for a long time. I’m a big fan of Vitamin C as a skin care ingredient in general, but stopped using it last year when I started using tretinoin (generic Retin-A). It’s generally advised not to mix tretinoin and Vitamin C in a single routine, though, if your skin isn’t sensitive (and you’re not spending a lot of time outdoors), it can be okay to use Vitamin C in the morning and tretinoin at night. It took a while for my skin to get used to the tretinoin, and my skin was very sensitive during that time; I just didn’t think my face could handle both. My skin is now used to the tretinoin, and I just switched to the micro-gel version (which I find to be much gentler), so when I had the opportunity to try this serum, I said, “Get on my FACE, Vitamin C!” Okay, I didn’t say that. But I thought it, and I still think it every morning, as I’m applying this serum.
WHAT IS IT?
O.S.T. Original Pure Vitamin C20 Serum ($25) is a Vitamin C powered serum that claims to exfoliate, brighten skin, fade acne scars/post-inflammatory hyperpigmentation (PIH), and remove blackheads.
Water, Ascorbic Acid, Ethanol, Sodium Lactate, Butylene Glycol, Glucose, Camellia Sinensis Leaf Extract, Rosa Davurica Bud Extract, Carthamus Tinctorius (Safflower) Extract, PEG-60 Hydrogenated Castor Oil, Sodium Hyaluronate, BIS-PEG-18 Methyl Esther Dimethyl Silane, Diethoxyethyl Succinate, Ammonium Acryloyldimethyltaurate/VP Copolymer, Xanthan, PEG-180, Gluconolactone, Beta-Glucan, Citrus Aurantium Dulcis (Orange) Oil, Zinc PCA, Panthenol, Niacinamide, Glycerin, Tocopherylacetate, Lecithin, Caprylic/Capric Triglyceride, Ubiquinone, Diisopropyladipate, Phenoxyethanol, Methylparaben
The ingredient list looks okay at first glance, as this serum does contain a multitude of good skin care ingredients. There are also some things about this ingredient list that I find confusing, but I’ll get to that in just a minute. First, the highlights:
Ascorbic Acid – Ascorbic acid is the source of Vitamin C in this serum, and it accounts for 20% of the serum. As a general rule, you want at least 10% for an effective formula, 15% is better, and 20% is pretty great. Topical Vitamin C has been scientifically proven as an effective topical treatment for a variety of skin conditions, including acne, reduction in photodamage, fading of scars, and strengthening the skin’s barrier function. It also promotes collagen production, and is often marketed as an anti-aging ingredient for this reason.
Unfortunately, Vitamin C in general is not very shelf stable. It’s extremely sensitive to light and oxygen; overexposure to either one of those things will cause it to oxidize rapidly, at which point it loses its efficacy. This is why it’s important for Vitamin C to be packaged in dark colored or opaque bottles – a clear bottle would render the product ineffective fairly quickly. It’s also important to use up a Vitamin C product within a a reasonably short span of time – 3 months is a good rule of thumb, but if your Vitamin C product darkens at any point, it’s time to stop using it. A darker product means it has oxidized.
There are many different sources of Vitamin C; Ascorbic Acid (which also happens to be an AHA) only represents one of them. Unfortunately, it’s not the best choice to be used topically. It’s effective, but it is a little less stable, and it is more likely to cause irritation than other C sources such as C-ester or magnesium ascorbyl phosphate (MAP).
If you’re interested in reading just a small sampling of the scientific studies surrounding Vitamin C as a skin care ingredient, here are some good places to start:
However, I am a bit confused about Niacinamide’s presence in this formula, as it is typically known to be incompatible with Vitamin C, especially in the form of Ascorbic Acid as it appears in this serum. Niacinamide and Vitamin C cancel each other out when mixed with one another in water-based solutions – which is what this serum is. Because Niacinamide is so low on the list of active ingredients in this formula, I’m guessing it’s not present enough to cancel out the efficacy of the Ascorbic Acid, but I am wondering what its role is in this serum. If any cosmetic formulators happen to be reading this and can shed some light on why Niacinamide is included in this formula, I’d love your insight!
Ubiquinone – Better known as CoQ10, Ubiquinone is an antioxidant that can help increase collagen production when present in large enough amounts. Ubiquinone is pretty low on the ingredient list in this particular formula, however, so once again, I find myself asking why it’s been included.
It’s worth mentioning that this formula also contains alcohol (which appears as “Ethanol” in the ingredient list). The alcohol is the only major red flag in the O.S.T. Vitamin C20 Serum according to COSDNA, where the ingredient ranks a 3 out of 5 as a potential irritant. I’ve mentioned here before that there are a large number of people who believe that alcohol is harmful to the skin in any amount and in any formula. There is also a line of thought that when included in a well-formulated product, it is a beneficial ingredient because it increases the absorption of other skin-healthy ingredients. Based on the research available, which is best summed up in this FutureDerm article, I’m personally inclined to fall into the “alcohol can be good in a well-formulated product” side of the great debate.
There are a few things I wish I could change about this serum: I wish it didn’t contain Niacinamide because of its incompatibility with Ascorbic Acid, and I wish it didn’t cause any sensation when I apply it. If I had my way, I would also probably forego the alcohol in this formula, even though I’m not entirely averse to alcohol as an ingredient in the right product.
All that said, my results from using the O.S.T. have been spectacular! When I began using this serum, I had some very visible hyperpigmentation spots on my right cheek that had been lingering for weeks with little to no fading. After the second week of using the O.S.T. Vitamin C20 Serum, I noticed they had faded dramatically, and by day 28, they were almost gone. My overall complexion also looked visibly brighter after about a week of use, and my overall skin texture appears smoother now than it did a month ago, especially in my nose area. I’m fortunate not to have very large pores or any blackheads, so I am unable to comment on whether this serum helps with either of those issues.
– Highly effective against acne marks/post-inflammatory hyperpigmentation (PIH)
– Improves skin texture
– Effectively brightens skin tone
– Packaged in a dark bottle to delay product oxidation
– Smells like fresh oranges
– Contains a high amount of Vitamin C
– Tingles a bit during application
– Contains a couple of questionable ingredients
– The Vitamin C source is just okay for topical application
Skin & Tonics Rating:
Performance: 5/5 – Very effectively fades acne marks, improves skin texture, and brightens as promised
Quality: 3/5 – The packaging is okay, but would be better as an airless pump. Overall ingredient list could use some improvement.
Value: 5/5 – Very well priced for such a highly effective product