Medik8 C-Tetra Lux Vitamin C Serum: a Guru Score of 69%

What the gurus are saying.

Every take we've logged from this product's reviews across YouTube. Click any row to watch the moment they said it.

All takes Yay takes Nay takes Mixed takes Hide sponsored

~Nay

"I did try the C-Tetra Luxe one, which is a richer oil and contains 14% tetrahecyldecyl ascorbate. I'm just not the biggest fan of oily textures. [...] I had no irritation whatsoever with it."

All 2 takes from Doctor Anne

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"I did try the C-Tetra Luxe one, which is a richer oil and contains 14% tetrahecyldecyl ascorbate. I'm just not the biggest fan of oily textures. [...] I had no irritation whatsoever with it."

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"The Medik8 C-Tetra Lux is a vitamin C serum, but I actually don't like that one as much. It is more on the oily side and it contains a vitamin C derivative, not ascorbic acid. It is one I'd rather reach for in the winter when I want something a little richer."

The Budget Dermatologist

724k subs

~Yay

"The biggest selling point in this is the vitamin C component. Now I will say the other main difference between these two, the 14% this is an oil-based serum. So if you are not used to or not looking for an oil-based type of serum this might not be for you. I actually like it. I like to use this at night, which vitamin C works at night. But the serum is so hydrating and just restores my skin and prevents dryness so well. So I like to use this one at night actually."

All 4 takes from The Budget Dermatologist

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"The biggest selling point in this is the vitamin C component. Now I will say the other main difference between these two, the 14% this is an oil-based serum. So if you are not used to or not looking for an oil-based type of serum this might not be for you. I actually like it. I like to use this at night, which vitamin C works at night. But the serum is so hydrating and just restores my skin and prevents dryness so well. So I like to use this one at night actually."

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"This next vitamin C by Medik8 C-Tetra Lux is an amazing option that has the derivative Tetrahexyldecyl ascorbate form of vitamin C. When you apply this to your skin it gets converted to L ascorbic acid. The wonderful thing about this derivative is that of all the inactive derivatives from my research and in my opinion will get you the best results with the lowest chance of irritation."

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"This is one of my all-time favorite THD ascorbate forms of vitamin C. It's the C-Tetra Lux by Medik8, it has 15% or 14% THD ascorbate in it and it has vitamin E in it and some other great antioxidants. What's different about this one is the consistency, this is an oil-based serum which is much different than we're used to for our typical water-based serums. So I actually love to incorporate this one in my routine at night, it's more of a face oil so it's definitely more like moisturizing."

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"It's a very different vitamin C serum that I have personally ever used before. Some people would agree with me that it's amazing and they love it, and others might feel like it's just not for them. [...] This is a vitamin C that is an oil-based serum, so this is going to go on the skin like a skincare oil, which I have not used a lot before, so it took some getting used to for me. I actually have put this into my nighttime skincare routine because it is an oil."

What the evidence says.

Independent of what the gurus think, this is what the published research supports about the main active ingredients here.

Vitamin C

Topical vitamin C is an antioxidant with reasonable evidence for dullness and uneven tone. It breaks down in light and air, so how a product is formulated and packaged matters as much as the percentage on the front.

Source: DermNet

Humectants and emollients

Ingredients like these draw water into the surface layers and slow how fast it leaves. The evidence is for comfort, softness and hydration rather than for changing the structure of the skin.

Source: DermNet

Vitamin E

Vitamin E is an antioxidant, and it is often in a formula to keep the other ingredients stable rather than as the active itself. It pairs well with vitamin C, though on its own the evidence for visible change is limited.

Source: NIH, National Library of Medicine

Frequently asked.

What is Medik8 C-Tetra Lux Vitamin C Serum?

A vitamin C serum from Medik8 in the C-Tetra Luxe line, formulated with a stable, oil-based vitamin C to brighten and hydrate skin.

Is Medik8 C-Tetra Lux Vitamin C Serum worth it?

The gurus mostly approve it, but with enough reservations to keep it in the middle at a Guru Score of 69%.

What is Medik8 C-Tetra Lux Vitamin C Serum's Guru Score?

Medik8 C-Tetra Lux Vitamin C Serum holds a Guru Score of 69%. That is our read on how warmly the experts talk about it, based on the verdicts of 2 expert reviewers we have collected.