The puzzle of Vitamin C serums - CSI Vitamin C + 12% Youth Serum review!

By Tina A. - November 14, 2013

Far be it from me to analyze the importance of Vitamin C in one's skincare routine: a ton of skincare experts out there have already praised its many benefits, which include a brighter complexion, free radical elimination, and stimulation of collagen production. What the experts don't really say though, is just how hard the quest for a good Vitamin C serum can be, especially since we're dealing with an ingredient that needs to be researched quite a bit beforehand!

So let me sum up the basics for you:
a. Vitamin C comes in a lot of forms, the most potent of which is considered to be L-ascorbic acid.
b. You need a high concentration of Vitamin C in your skincare item, if it's to actually make a difference. Anything less than 10% is considered inadequate.
c. Vitamin C "expires" quickly, if not stored properly. It should come in tinted glass bottles, that prevent its degradation from light exposure (you would know that it's gone bad if your product has changed color to a more yellow/brown shade).

To all that above, let me add a personal d: there's not a lot of brands that make pure Vitamin C serums, especially not in Europe, and when they do, they charge quite a lot. It seems that the U.S. market carries a wider variety of such products, so that's exactly where I looked for mine.

CSI (Cosmeceutical Sciences Institute) Vitamin C + 12% Youth Serum thankfully ticked all the boxes! It's a 12% Vitamin C serum, and it's only two ingredients are butylene glycol and L-ascorbic acid. Now, I've read somewhere that butylene glycol (a solvent mainly used for oils) is considered an irritant in large concentrations, but, so far, my very sensitive skin hasn't complained - and when I say very, let me remind you that I'm the kind of minority that doesn't get along with Caudalie Beauty Elixir, so, that says something!

My preferred method of using it, is applying 3-4 drops in the morning all over my face*. I let it absorb for about 15 minutes (apparently that ensures maximum capacity, probably cos you're not diluting the product straight away) and then continue with my moisturizer/spf. It's a clear and practically scentless formula with a somewhat oily texture, though not greasy, which I believe keeps my face better moisturized throughout the day: on days when I don't use this, my makeup doesn't seem to hold up as well. And after a couple of weeks of use, I can tell that my post-breakout scars seem to fade a lot quicker, while a sun spot that I've had for years is a lot less obvious. Unfortunately, I can't speak about new collagen formation, but it seems that my skin is in overall better shape when I use this!

I enjoy using this product, and unless I stumble across another serum that intrigues me more, I plan to repurchase. So far, I rate it higher than the Apivita Radiance Serum (green bottle), which, while it does give you better skin, in all likelihood doesn't achieve that through it's Vitamin C concentration.

*Contrary to popular belief, Vitamin C is not a PM-only skincare ingredient: in fact, using it underneath a sunscreen (or a moisturizer with spf) provides an even better protection against those nasty UV rays!

Hope this was helpful!
Let me know what your experience with Vitamin C products has been in the comments!

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  1. As speaking I remember my La Roche Posay Vitamin C eye cream that it did make a huge different for my under eye black sircles, and havent find something so drastic again. This serum sounds just perfect for my imperfections(small acne scars or whatever) and I just love Vitamin C!!!! Thanks for the amazing Review and the further wallet damage doll!!! <3

    1. @Irene Blushing Loves: Thank you for that recommendation, I'm looking for a good eye product like crazy! And yes, Vitamin C is one ingredient that one simply must include in their skincare routine! :)

  2. This is very helpful! I live in Florida and have sensitive skin, so I need all the protection from the sun that I can get. What does "12% youth serum mean?"

    1. @L Olsen: 12% means that the concentration of Vit C in the formula is 12%, as for "Youth Serum", that's simply what the brand decided to name the product!

  3. I am actually a HUGE fan of that Apivita serum but am now curious about this one.

    1. @Marina(Makeup4all): Yup, I remember us exchanging tweets about the Apivita one! I like it too, but I think the results are mainly from the other ingredients, not the ascorbyl glucoside (which I believe is not a very potent form of Vit C to begin with)!

  4. I just ordered this last night and cannot wait to try it.


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