Can’t Decide Which Form Of Vitamin C To Use? This Serum Has 3!

by Gio

dr dennis gross c collagen brighten and firm vitamin c serum

Confession time: I’m using a serum with Vitamin C + niacinamide.

Shock horror!

I know, I know, you’ve probably heard something horrible will happen if you mix those two together.

You’ll get beautiful, glowy skin.

I know, not that horrible, isn’t it? Me thinks it’s time to bust some myths so you can enjoy amazing serums like Dr Dennis Gross C+ Collagen Brighten & Firm Vitamin C Serum. 

Vitamin C

Dr Dennis Gross C+ Collagen Brighten & Firm Vitamin C Serum has not one, not two, but three types of Vitamin C:

All this vitamin C helps your skin fight wrinkles, fades dark spots and gives your skin a beautiful glow.

But, it may be a tad too much for sensitive skin. My skin is used to Vitamin C so I have no problems with this serum but if it’s your first time with this antiaging superstar, take things slow and use it only three or four times a week. Once your skin has gotten used to it, build up frequency.

Related: Types Of Vitamin C In Skincare Products: What They Are And What They Do


Niacinamide is another antiaging superstar that’s part of any everyday skincare routine. This multitasker:

So why do people say it doesn’t play well with Vitamin C?

Here’s the deal: when you mix the two, the solution turns yellow. That’s usually the colour of death for Vitamin C. It means it has become useless.

Usually. Because in this case, the yellow colour is caused by the formation of Niacinamide Ascorbate. Basically, an electron transferred from Vitamin C to Niacinamide, holding them together.

But this reaction is reversible. As they travel deep into your skin, Vitamin C and Niacinamide go their merry separate ways so you don’t have to worry about this chemical reaction at all.

The best part? Niacinamide Ascorbate isn’t as useless as it seems. Studies show it can still help fight sun damage.

Related: Can You Use Vitamin C And Niacinamide Together?


The three forms of Vitamin C aren’t the only antioxidants here. Dr Dennis Gross C+ Collagen Brighten & Firm Vitamin C Serum also has superoxide dismutase, ubiquinone, quercetin…

I’m particularly thrilled to see that superoxide dismutase has made it onto the ingredient list. It’s one of those antioxidants that you come across rarely, which is a shame because it’s super powerful.

Superoxide Dismutase destroys Superoxide, one of the worst types of free radicals. Superoxide is the primary trigger of inflammation. This inflammation then turns into wrinkles and dark spots and may have trigger a bout of acne!

Give me a dose of Superoxide Dismutase pronto!


So far this serum sounds perfect, doesn’t it?

Well, there is one little nasty thing lurking in here: SD Alcohol 40-B. I guess it’s here to help the active ingredients penetrate skin more easily.

But too much alcohol can be drying for the skin. You can counteract this by applying moisturiser afterwards, which you should do anyway. I did this and had no problem at all.

But again, if you have sensitive or very dry skin, the combo of alcohol and lots of Vitamin C could irritate your skin. Be careful!

Let’s Put It To The Test: Personal Use & Opinion

Dr Dennis Gross C+ Collagen Brighten & Firm Vitamin C Serum is an orangey caramel in colour. This does NOT mean Vitamin C has gone bad. Caramel is one of the ingredients here. 🙂

The lightweight, gel-like texture sinks quickly into my skin without leaving a sticky feeling behind. I apply it just after cleansing to allow it to penetrate more deeply into my skin.

The only thing I don’t like is the scent. Dr Dennis Gross didn’t add any perfume to the serum so what I’m smelling is the natural odour of the ingredients. Let me tell you something, they DON’T smell good. But, I’d rather put up with that for a few seconds than the irritation caused by added fragrances. Just saying…

Besides, it works wonders. After a couple of weeks, I could already see my skin was more radiant than usual. My skin felt a little tighter, too. Of course, the serum can’t lift skin that has already sagged (you still need a little nip and tuck for that) but it keeps everything tight.

The good cocktail of antiaging ingredients fights wrinkles and boosts collagen, keeping your skin in good, youthful condition. There’s enough Vitamin C here to lighten your dark spots as well but I can’t vouch for it personally. I’m lucky I don’t have any yet. I’m planning to keep it that way. 😉

Available at: $78.00/£72.00 at Nordstrom and SpaceNK


Ingredients: Water, Glycerin, 3-O-Ethyl Ascorbic Acid, Niacinamide, Glycereth-7 Triacetate, Lactic Acid, SD Alcohol 40-B, Hydroxyethylcellulose, Dimethyl Isosorbide, Ascorbic Acid, Collagen Amino Acids, Superoxide Dismutase, Glycine, Carnitine HCl, Ubiquinone, Hexylresorcinol, Emblica Officinalis Fruit Extract, Hydrolyzed Soy Protein, Tetrahexyldecyl Ascorbate, Isoquercetin, Mandelic Acid, Pueraria Lobata Root Extract, Curcuma Longa (Turmeric) Root Extract, Phytic Acid, Citric Acid, Tetrasodium EDTA, Sodium Citrate, Butylene Glycol, Xanthan Gum, Polysorbate 20, T-Butyl Alcohol, Sodium Hydroxide, Polysorbate 80, Denatonium Benzoate, Benzyl Alcohol, Phenoxyethanol, Sodium Benzoate, Potassium Sorbate, Caramel.

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gt May 21, 2018 - 6:02 pm

Some reviewers say that it was difficult to use for daytime because it took too long to absorb or to use under makeup. Did you have that issue?

Gio May 27, 2018 - 7:05 am

GT, no I didn’t. But then, I always wait a few minutes between application of each skincare product. I also don’t use foundation anymore, just concealer these days.

Rebecca August 24, 2018 - 11:34 pm

I haven’t used Vitamin C products much but I went ahead and took the plunge with this one. Scent doesn’t bother me and I don’t have issues with putting makeup on over it, but every time I use it, my cheeks get flushed. I tried mixing just one drop into my moisturizer and it still happened. Should I stick with it, perhaps in the evening, and see if my skin adjusts, or should I switch to something gentler? It doesn’t seem to be actually irritating my skin, but the redness sticks around for awhile and then I have to cover it with more makeup.

Gio September 7, 2018 - 12:22 pm

Rebecca, mmmm, mixing vitamin C with niacinamide like this serum does is safe for most people. But there’s a small minority that reports your same problem. Try switching to a vitamin C serum without niacinamide and see if that helps.

Jane September 18, 2018 - 12:36 am

I’ve been having the same issue with this product- my cheeks immediately flush and remain red for 15 minutes or so. I tolerat other vitamin c products well (Like hylamide C25 booster)- so maybe it’s the combination of C + niacinamide for me. That said, once the redness dissipates, my skin looks great!

Separately, do you use this in the AM? I worry about the lactic acid – I try to avoid exfoliating in the AM but I also like to use C in the AM…and this contains both!

Gio September 19, 2018 - 11:06 am

Jane, if you get the flushing, I’d switch to something else without lactic acid you can use in the morning. In your case, it’s best to use vitamin C in the morning and niacinamide at night.

Jane September 30, 2018 - 4:01 pm

Follow-up: I think I figured out the issue. I was using this right after my PC resist toner, which is high in niacinamide. I was probably going crazy on the niacinamide given that it was among the top few ingredients in both products. When I use the serum alone, flushing gone.

Rebecca CONNELLY September 11, 2018 - 11:09 pm

Thanks–I have been sticking with it and not massaging it in, but rather patting it in, and it seems to be getting better. And I’m trying to get rid of my cheesecake picture and replace it with a real one, but I’m not sure what’s going on!

Gio September 13, 2018 - 4:55 pm

Rebecca, the avatar images comes from Gravatar. If you have an account there with this email, change the profile picture and it should be fine. 🙂

Rebecca Connelly September 11, 2018 - 11:21 pm

Let’s try again with an updated email!

Gio September 13, 2018 - 4:52 pm

Rebecca, 🙂

Gio October 4, 2018 - 7:40 pm

Jane, I’m replying here because we’ve run out of space up there. Glad you were able to figure out the issue.

Jane November 3, 2018 - 3:36 pm

One more question! Do you know if “3-0 Ethyl Ascorbic Acid“ (DDG product) is the same ingredient as “Ethyl Ascorbic Acid” (in Hylamide/Niod product)?

Gio November 23, 2018 - 9:44 am

Jane, yes they are. 🙂


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