CSI Vitamin C + 12% Youth Serum

 CSI Vitamin C + 12% Youth Serum

4.4

20 reviews

85% would repurchase

Package Quality: 4.4

Price: $$$

Package Quality: 4.4

Price: $$$

INGREDIENTS

Butylene glycol, L-ascorbic acid

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on 11/23/2017 6:33:00 PM

Age: 56 & Over

Skin: Acne-prone, Fair-Medium, Cool

Hair: Brown, Other, Other

Eyes: Hazel

Excellent product. I was skeptical at first, but after just a few applications my skin looked firmer, smoother, and brighter. I have sun damage on my chest—the skin there is rougher and redder than elsewhere—and the CSI has made it look much better. I've also applied it to a burn scar on my hand that was healing slowly, and it worked wonders. My facial skin is oily, but the serum hasn't caused any problems at all. And the price is amazingly cheap for a Vitamin C product if you buy it directly from Vitacost (which often has sales, too). I usually use it twice a day as the last step in my skincare regimen; sometimes I skip it in the mornings. I've already repurchased this twice.

3 of 3 people found this helpful.



on 8/20/2017 2:52:00 PM

Age: 36-43

Skin: Normal, Fair-Medium, Warm

Hair: Brunette, Straight, Medium

Eyes: Brown

This serum is really nice - it keeps my skin really smooth, especially my undereyes. I use it at night and in the morning, after washing my face and before moisturizer. My skin feels smooth and hydrated all day. I've never been super into skin care but I'm glad the SC board recommended this. It's a great product!

4 of 4 people found this helpful.


on 7/27/2017 9:48:00 AM

Age: 36-43

Skin: Dry, Fair-Medium, Not Sure

Hair: Brunette, Straight, Fine

Eyes: Blue

I literally just re ordered this for a second time. I really like it and as I was nearing towards the end realised I definitely don't want to be without it. I am really satisfied with this for the brightening and glowy effect it offers my skin. I only use at the pm (before finishing off with darphin's intral baume) seeing I only do a splash of water in the am (and a bit of the aforementioned darphin product around the eye area and follow with mac strobe cream before make up). A bit of a tiny tingly sensation sometimes depending on the condition of my skin, smelled a lot stronger in the beginning, afterwards, it seemed to die down a bit? But it remained fine. I keep it in the drawer of my night stand. Retails for 16$ + 10$ shipping to Greece from vitacost.

2 of 2 people found this helpful.


on 6/11/2017 1:15:00 AM

Age: 36-43

Skin: Sensitive, Fair, Neutral

Hair: Brown, Straight, Fine

Eyes: Brown

I'm not new to the C serum game, and gave this a try for a couple of reasons. I had most recently been using Ole Hericksen for well over a year. I felt as of recently it really had not been doing much for my skin. Not really sure if the product had changed, or my skin simply need a stronger concentration. I had noticed this brand mentioned on the boards, and had a coupon for Vitacost house brands, so I figured it was worth a shot. At just over $16USD this is by far the least expensive C serum. The only way to get is for less is to DIY. The consistency is different that other C serums, this is thinner and almost oily feeling. My skin was not accustomed to the higher C concentration, so this did burn a bit upon application. After a few days of use, I am very impressed. This has helped my skin feel more smooth, and it looks brighter.

1 of 1 people found this helpful.


Age: 36-43

Skin: Dry, Fair-Medium, Neutral

Hair: Brunette, Straight, Fine

Eyes: Brown

This serum came highly recommended from skin care board (thanks ladies - xoxox!) It's a great Vitamin C serum for sensitive/acne/reactive folks as it has only 2 ingredients instead of a laundry list of ingredients. I use it in AM in effort to boost SPF protection. It's in an oil but it isn't too greasy and seems to sink in fairly quickly. I have dry skin. For the price you just can't beat it!

My dropper doesn't "hold" the liquid in. It drips before I squeeze bulb. That IRKS me!!! I"m hoping maybe I just got a bum bottle and my next bottle won't be like that. I don't think I've seen anyone else mentioned it.

The smell isn't great but Vit. C serums almost always are a little stinky. That just how the ingredient is.

Vitamin C serums are notorious for being difficult to keep stable and potent. This one really gets high marks for its stability. I have previously used PC C15 and it always seemed to start changing colors before i used up bottle (not to mention it costs $30 more). I also use The Ordinary C23 at night (not every night). I REALLY like this one, faded some spots on me quickly. It's formula is unsuitable for day time. So this CSI fits the bill for me.

Purchased from Vitacost.

2 of 3 people found this helpful.


on 5/20/2017 6:53:00 PM

Age: 36-43

Skin: Dry, Fair, Cool

Hair: Blond, Straight, Medium

Eyes: Blue

Liking it! I believe a good C serum should be part of any anti-aging routine, so when this came so highly recommended by the experts on the skincare board, I was on board. To begin with, it is an L-ascorbic acid serum (LAA), which is usually unstable. However, this formula is special because it is anhydrous (no water). It is usually water which causes LAA to oxidize and be ineffective. The CSI serum has only two ingredients, Butylene glycol and L-ascorbic acid, so if you have sensitive skin and seek a limited ingredient product, this may be for you. It seems so stable, that I can order a few bottles a once and it doesn't go bad, remaining clear and fresh in the bottle with no need to refrigerate. I did like Nufountain's c20+ferulic, however even when stored carefully, it would often oxidize before I could finish a bottle, which was an annoying waste. Getting back to CSI. So does it deliver? Well, I have used it consistently for about 2 months and have found that seems to help lighten some hyperpigmentation and give more even skin tone. The results aren't stunning, but I have never had a life (or skin) changing experience with an antioxidant serum. I think the idea is to use it consistently as a preventative measure. It is supposed to help collagen strength prevent wrinkles and sun splotches, which I am all for even if the results don't show up over night. Anyway, this stuff did't cause me any dry or peely skin, which surprised me because I have very dry skin and have had that experience with other brands (Silk Naturals, for example). The consistency feels a bit oily and spreads easily, but it dries within a few minutes. Sunscreen and makeup can be applied over it with no product balling. It does cause a warm sensation when first applied, but not burning, so I am not bothered. Haven't broken out from it, but I'm not acne prone. My one complaint (ergo the lippie off) is that this stuff turns my skin yellow at night. It's not a disaster because it rinses off in the morning, and I've been informed that it just means the product is doing it's job and and has oxidized on my skin during the night, which is not harmful to the skin. However, I don't really love the being turned yellow factor, and I'm suspicious that it means it is oxidizing so fast as to not be able to do its job of scavenging free radials. Also, I noticed that it turned the collar of my bathrobe yellow, so that's not awesome. The price point, about $16.00 on Vitacost, is obviously very reasonable. For the moment, I am overall happy with the price and results and will repurchase.
Edit: I will not repurchase. I noticed my skin was getting noticeably yellow from this stuff. When I stopped using it, the yellowness stopped. IDK if this is an effective antioxidant, but I don't want a skin care product to make me look like I have hepatitis. It seems to work for lots of other people, so I am not taking any more lippies off. Maybe it just didn't work out for my skin. PM me if you know an awesome C serum because I am moving on.

4 of 4 people found this helpful.


on 10/14/2016 10:11:00 AM

Age: Unknown

Skin: Oily, Fair, Neutral

Hair: Brown, Wavy, Fine

Eyes: Hazel

This serum has been an absolute life saver for my skin! I've tried vitamin C serums in the past, & they have irritated my skin something terrible. I am 2/3 through this bottle & have already repurchased this one. No irritation whatsoever! Thank you to the skin board; otherwise, I would've never known about this perfect (for me) serum. It leaves my skin glowing, but not in an oily way, & my acne scars have faded to nothing. It really is unbelievable...

5 of 5 people found this helpful.


Age: 30-35

Skin: Combination, Fair, Neutral

Hair: Brunette, Curly, Medium

Eyes: Brown

No one is more shocked than I am at how much I've been enjoying this serum! I had in my mind that my skin simply couldn't tolerate L-AA, at any percentage or frequency, after the two serums that I tested in the past left me a little clogged up and majorly irritated. But I was wrong - I just had to find the right one. This never would have crossed my radar if it weren't for the skin board so I'm thankful for them. I won't be looking any further.
My skin is complicated (to say the least..). Combination, clog prone, SD that flares its ugly head if I'm not careful, aging, sensitive, reactive (hives, dermatitis/eczema), very prone to dehydration (yet rebels just as badly if it's overly moisturized). *Eye roll*
I began using this on July 15, so I'm right around the 10 day mark and have nothing but positive words to report. I do plan to update my review after a good amount of time has passed using this serum though. I don't have a ton of sun damage or major PIH to fade, just noticeable uneven-ness in my skin tone that annoys me to look at when I'm not wearing makeup.
I began using two drops - two times a day, and the first 3 days it stung a little (not terribly, but it caught my attention) so, since I rotate other actives (AHA, BHA) in the evenings, I decided to back off of using this in the evenings and just apply in the A.M. until my skin gets a little more used to L-AA. It's been working well. It doesn't irritate or break me out. Praise the heavens. I instantly noticed my skin looks smoother and more firm as well (wasn't expecting that) - a pleasant surprise.
It does have a specific smell to it (it's the glycol) - It's certainly not terrible but it is noticeable if you're not expecting it. This does fade immediately after applying though.
It's not oily, it's not drying - it's not even noticeable that it's there on my skin.
When I tried to apply it to dry skin, I found it can be difficult to spread around only using the suggested amount of 2-3 drops, so I've found dampening my face before applying fixes this. I wait several minutes (until it all dries down) to apply any moisturizing products overtop.
Such a minimal ingredient list (a heaven send for those of us who are sensitive but don't have negative reactions from butylene glycol) and a more than fair price point (around $17 from vitacost.com). I'm happy with it and would definitely recommend this.

8 of 8 people found this helpful.


Age: 19-24

Skin: Acne-prone, Fair, Cool

Hair: Brunette, Wavy, Fine

Eyes: Hazel

I've been using this serum for a few weeks now. I'll start with a bit of my skin background for reference.

I have extremely clog prone skin. Most things clog me and this really limits the skincare I can use. I've tried many different vit C serums in the past which all either broke me out, irritated me, or did nothing. A few months ago I tried the Nufountain 20% with ferulic which broke me out quite badly and I gave up on vit C serums for a while after that. I most recently tried the Hylamide C25 which I do still like and use a few times a week, and you can go read my review on that serum to see what I think about it in depth. Even though I like the Hylamide, it can be drying when used every day and I wanted to continue to try other C serums. The CSI was kindly recommended to me by BarbiH who has a similar clog-prone skin type to myself.

This serum has only 2 ingredients, butylene glycol and l-ascorbic acid. Your ability the use this serum will depend almost entirely on if your skin tolerates butylene glycol or not. For many sensitives and acne prones who's skin can't handle a long ingredient list this serum is a worthy option.

The serum is completely clear and anhydrous and very stable like the Hylamide. While the Hylamide had a thinner, dry oil-like texture the CSI also feels somewhat oily but is thicker in consistency and somewhat moisturizing (on my skin). You only need a few drops and it dries down fairly quickly.

I have not experienced any sensitivity or tingling with this serum. I believe this is because my skin is able to tolerate higher levels of C like the much stronger Hylamide, as well as 15% and 20% concentrations of l-ascorbic acid. This serum is only 12% which is why I think it would be a great option for sensitive skinned people, or those who are trying vit C for the first time.

I've been using this serum in the morning over my other fave aox serum (PSF Berry Beneficial serum) and under sunscreen and again at night over the PSF and under my HG moisturizer, argan oil. I'm not clogged or broken out and my skin looks uniform in tone and glowy. While the Hylamide had a much stronger brightening, lightening and skin refining effect the CSI provides a more gradual glowy and brightening effect on my skin. I'm really loving it and I think it's becoming a staple in my routine.

Overall, I'd recommend the CSI to sensitive skinned folks, first time C users, easily clogged people, and those on a budget (this is the most wallet friendly C serum I've used, it's normally less than 20$ on Vitacost).

19 of 19 people found this helpful.


Age: 30-35

Skin: Acne-prone, Medium, Warm

Hair: Brown, Wavy, Medium

Eyes: Brown

My skin is very finicky but this does not cause me any breakouts at all. I have combo skin and I noticed my skin looks a lot smoother, hydrated and tightens my pores! I was not expecting any of these things. It works to fade spots but slowly. Its very inexpensive. I'm currently only using this at night but will be adding this to my daytime routine as well. You only need a few drops but it does dry down after about 15 minutes with no stickiness. This product has made me content. I would definitely recommend it.

5 of 5 people found this helpful.


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