What Causes Wrinkles?

In younger skin, cells called fibroblasts are highly active, producing a rich, organised matrix of collagen and elastin. As we age, these fibroblasts naturally slow down, and specific enzymes (called MMPs) begin to break down existing collagen faster than it is replaced. This gentle shift in your skin’s deep structural matrix is what creates the fine lines and wrinkles that map your life's journey.

What Causes Loss of Firmness?

Think of healthy elastic fibres like tiny rubber bands that help your skin snap back. But with cumulative sun exposure, UV rays can alter how our cells function, causing our fibroblasts to produce less resilient elastin. Instead of clean, recoil-ready fibres, the elastin accumulates into a disorganised network. This structural change reduces the skin's ability to bounce back, leading to a natural relaxation or sagging.

Tested at the Cellular Level — The Manchester Patch Test Assay & Spatial Transcriptomics

The Process: Manchester Patch Test Assay: Intra-subject controlled, double-blinded study on human volunteers with skin biopsies taken and biomarkers examined under microscope. Validated & bench-marked against prescription product. Spatial Transcriptomics: After the patch test, the skin biopsies from treated and untreated sites are sliced wafer-thin and placed in the Xenium machine. It tags and images the RNA for 300 genes to show which genes switched on, in which cells, and exactly where in the skin. The Purpose: Manchester Patch Test Assay: Rapidly models 6 months of use on live human skin. Spatial Transcriptomics: Provides a precise map of how the product changed skin biology at the cellular level. The Result: Scientifically proven to increase fibrillin deposition in human skin 32% higher relative P4HA2 transcript abundance in superficial fibroblasts; increased in 5/5 donors in spatial transcriptomics Approximately 2.4-fold higher expression of the antioxidant enzyme gene SOD3 in spatial transcriptomics.

Measured on the Surface — Clinical Trial

The Process: 32 people have baseline professional Visioscan & Skin Gloss Metre in controlled conditions to measure wrinkle depth & brightness, images are taken before using the product, at 7 days, 28 days and 56 days. Computer-measurements are taken and compared to the baseline. The Purpose: A good study to see if visual improvements are obtained from use of the product. The Results: Clinically proven to reduce the appearance of fine lines & wrinkles from day 7 Clinically proven to deliver an immediate boost to skin radiance maintained at 56 days

Perceived in the Mirror — Consumer Trial

The Process: 45 people are provided with the product to use for 28 days, volunteers are asked questions about their experience at 0, 7 days, and 28 days. The Purpose: This study is useful to understand volunteers' experience from product use, while it lacks rigorous scientific credentials, it helps to ensure that a person's experience aligns with the scientific results. The Results: 91% experienced brighter skin within 7 days. 87% said skin appeared firmer and more plump after use. 73% said they would switch from their current vitamin C product.

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Pro-Helix C

Name: Pro-Helix C
Brand: The Skin Diary
SKU: TSD-PHC
Price: 1330.00 SEK
Availability: InStock

Pro-Helix C

Collagen Peptide Brightening Serum

18 total reviews

Targets skin’s lost elasticity for firmer, brighter skin.

A luxurious milky serum that goes beyond typical vitamin C. In a single morning step, discover clinically proven brightening from the first application with cellular renewal for firmer, more elastic skin. In a pH neutral formula; gentle enough for sensitive skin.

Immediate & lasting radiance: Clinically proven to increase skin brightness.
Visibly reduces fine lines & wrinkles: Reduction in the appearance of fine lines and wrinkles in 7 days.
Restores skin firmness: Increase in elastic fibres in cellular testing.
Suitable for sensitive skin: Dermatologically approved pH neutral formula.

Free gift with this purchase

Firming Tool Worth 200 kr

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Pro-Helix C

1 330 kr

KEY BENEFITS

Brighter, More Radiant Skin

Clinically proven to deliver an immediate boost to skin brightness. 94% showed brighter skin within 7 days.^[1]

Reduces Fine Lines & Wrinkles

Clinically proven to reduce visible fine lines and wrinkles in as little as 7 days^[2]

Improves Skin Firmness & Elasticity

Human skin biopsy study showed a significant increase in elastic fibres. 87% of participants said their skin appeared firmer and more plump after four weeks of use.^[3]

Protects Collagen

2.4x boost in key antioxidant defence. Helping protect collagen from environmental stressors.^[4]

View Citations

[1] Proven via independent clinical study using a skin gloss meter test of 35 people at 7, 28, and 56 days.[2] Proven via independent clinical study of 35 people at 7, 28, and 56 days.[3] Independent Manchester Patch Test assay biopsy study of human skin found a significant increase in fibrillin, a key protein of the skins elastic fibre network. In a separate independent consumer study of 45 people over 28 days 87% of participants experienced firmer more plump skin.[4] SOD3 gene expression in basal keratinocytes. Spatial transcriptomic analysis of human skin biopsy.

"We have evidence of a measurable structural change within human skin, and that's where the story becomes quite different from a conventional vitamin C serum."

Dr. Clare Kiely

CONSULTANT DERMATOLOGIST

SWITCH ON MORE THAN GLOW

Proven Results

Rigorously tested across all three dimensions of our Cell-to-Surface™ standard

SKIN RESULTS FIBRILLIN

BEFORE AFTER 4 WEEKS
BEFORE AFTER 8 WEEKS
BEFORE AFTER 8 WEEKS

1 3

BEFORE AFTER

SEE THE DIFFERENCE RESULTS BEYOND VITAMIN C

TESTED AT THE CELL

32% increase in key collagen-forming gene

2.4x Boost in key antioxidant defence.

MEASURED AT THE SURFACE

7 Days Significant reduction in wrinkles in as little as 7 days. 94% Clinically proven brighter skin in 7 days

PERCEIVED IN THE MIRROR

87% Noticed visibly firmer skin

Why Switch From Your Current Vitamin C Serum?

Pro-Helix C goes beyond glow alone

L-Ascorbic Acid (Gold Standard)Pro-Helix C

Improves Brightness

94% of Pro-Helix C clinical trial participants showed brighter skin within 7 days

Protects Collagen

Vitamin C contributes to normal collagen formation for the normal function of the skin.

Provides Antioxidant Protection

Vitamin C is the most plentiful antioxidant in human skin. It protects against environmental stressors by donating electrons to neutralise free radicals. Pro-Helix C takes this further showing a 2.4x boost in key antioxidant defence signals created by the body.

Increases Elastic Fibres for Visibly Firmer Skin

In a human skin biopsy study, Pro-Helix C showed a significant increase in elastic fibres, namely fibrillin.

Formulated for Sensitive Skin

Pro-Helix C uses a combination of THDA vitamin C and acetyl-zingerone to create a lipid-soluble form of vitamin C that is stable. This means we have been able to formulate the product at a neutral pH with no added fragrance, which doesn't cause irritation to sensitive skin and doesn’t block pores.

Powered by Collagen-Signalling Peptides

Pro-Helix C combines two peptides: one that signals collagen repair and another that switches on the growth-factor pathway directly for firmer, more elastic skin.

More Than Vitamin C.

BRIGHTEN

15% THDA Vitamin C

The lipid-soluble form. Highly stable, well tolerated, and it penetrates properly rather than sitting on the skin's surface.

REBUILD

4.5% Dual Peptide Complex

Two complementary signals telling your skin to build new collagen - not just protect the old.

PROTECT

0.5% Acetyl Zingerone

The bodyguard. Most antioxidants are depleted the moment they neutralise a free radical. This one keeps going; protecting your collagen for hours after you apply it.

View the full INCI

Aqua, Tetrahexyldecyl Ascorbate, Glycerin, Dipropylene Glycol, Simmondsia Chinensis (Jojoba) Seed Oil, Dicaprylyl Ether, Maltodextrin, Glycine Soja (Soybean) Seed Extract, Acetyl Zingerone, Palmitoyl Tripeptide-5, Collagen Amino Acids, Squalane, Tocopheryl Acetate, Sodium Hyaluronate, Lecithin, Ethylhexylglycerin[1], Sorbitan Isostearate, Hydroxyethyl Acrylate/Sodium, Acryloyldimethyl Taurate Copolymer, Sodium Acrylates Copolymer, Polysorbate 60, Phenoxyethanol, Citric Acid

DEEP RESULTS TAKE TIME TO BUILD

What to Expect

1 Week

Within 1 week, your skin will appear more radiant with a healthy-looking glow.

1 Month

By 1 month of continued use, you will start to see early visible improvements. Your complexion appears brighter, more even and refreshed. Daily antioxidant support helps defend against environmental stressors that can contribute to dullness and uneven skin tone.

3 Months

By 3 months your skin is building resilience so it feels firmer and smoother. Fine lines appear less noticeable, while the complexion looks visibly plumper and more luminous.

6 Months

As 6 months of use come around, you'll feel and see the full cumulative effects: skin appears noticeably firmer and more elastic, with improved overall radiance and more even-looking tone. Your complexion looks healthier, brighter and more youthful.

FAQs

How to Use

Apply evenly to the whole face every morning before your sunscreen.

What texture is it?

Pro-Helix C is a lightweight, fast-absorbing milky serum texture that layers seamlessly with sunscreen and makeup.

Does it cause irritation?

No. Pro-Helix C has been dermatologically tested and approved. Clinically proven non-comedogenic. Suitable for even sensitive skin.

How long will it take to see results?

Consistency is key with any topical skincare product. So it's important to commit to daily use for best results.

Within 1 week, your skin will appear more radiant with a healthy-looking glow.

By 1 month of continued use, you will start to see early visible improvements.Your complexion appears brighter, more even and refreshed. Daily antioxidant support helps defend against environmental stressors that can contribute to dullness and uneven skin tone.

By 3 months your skin is building resilience so it feels firmer and smoother. Fine lines appear less noticeable, while the complexion looks visibly plumper and more luminous.

As 6 months of use come around, you'll feel and see the full cumulative effects: skin appears noticeably firmer and more elastic, with improved overall radiance and more even-looking tone. Your complexion looks healthier, brighter and more youthful.

5 stars: 18 (100%)
4 stars: 0 (0%)
3 stars: 0 (0%)
2 stars: 0 (0%)
1 star: 0 (0%)

Extra glow from the word go!

I’ve been using skin diary day and night creams for the last 9 months. Recommend to me by my skin Aesthetic professional. Was so happy to see the vitamin C product - pro helix C was becoming available. This was the product I felt was missing from my skin regime.
I have used the 3 day pro-helix trial and found this to feel lovely on my skin no irritation whatsoever just an extra glow which is just what I want from my skin care products. This will definitely will be part of my daily routine. Thank you ☺️

As a big fan of Skin Diary products, I was

As a big fan of Skin Diary products, I was delighted to try a sample of the new vitamin C product. It was lovely to apply, very smooth and left a lovely glow on my skin. Looking forward to adding it to my regular Skin Diary routine.

Amazing product

Amazing product. It feels and smells great. Very light and is absorbed instantly. I’ve only been using for a very short time but I’m sure I can see a difference in my complexion already. Lovely

I really like this serum

I really like this serum.. it’s light, easily absorbed and non sticky like other brands. I am only using it a short time but I can already feel the difference.

I have just started using new pro helix

I have just started using new pro helix. It has a beautiful light texture and is easily absorbed. I love all the skin diary products. It has become my regular night and morning routine
Vitamin C is so important to the skin and this new product looks to deliver exactly what it says.
Thanks skin diary.

Love it

Love it , a smooth easy to apply texture. I have very sensitive skin and had absolute no irritation. I would highly recommend.

So far, I’ve only used the sample but love the texture.

So far, I’ve only used the sample but already I prefer the texture to my current, oily Vitamin C.
I plan to order as I love my Skin Diary night cream so much. Hoping for great results.

Lovely product

It’s my first day using it but what I can say is that the texture is lovely and it sinks in really well, quite different from my previous, more oil-based vitamin C serum. The smell is amazing too. Well done Skin Diary!

Easily absorbed, soft and luminous skin

Having used a lot of vitamin C products, this is one of my favourites. The product is a light creamy texture and easy absorbed. I have dry skin and this sunk in nicely, without an oily residue. It also has a pleasant smell. The serum doesn't pull under other products or make up. After a few weeks of use my skin was more even and luminous, even though this was over the summer months when even with use of sunscreen my skin normally colours a little. Dark spots were noticeably lighter and with continued use, continued to improve. A really nice effective product.

I have been looking for a great Vitamin C serum

I have been looking for a great Vitamin C serum and am hoping I’ve found it with this one from Skin Diary. The texture is lovely and creamy - not sticky like a lot of vitamin c serums/drops.
My skin seemed instantly brighter and am hoping this might become my go-to vitamin C!

What a gorgeous new vitamin C product, love the

What a gorgeous new vitamin C product, love the texture, love how it melts into the skin and can already see a glow after short term use.

I love this!

I’m writing this having only used the three day trial so can’t comment on its effectiveness over time but I’ve loved using it. I’ve often avoided using skin creams during the day as my skin is quite oily and they can feel uncomfortable and rather ‘de trop’ even though I do know I need them. This was lovely to apply, it felt like it wasn’t even there, and best of all it actually made my skin look good from the moment I put it on. I’ll definitely be buying a full bottle of this today and many more in the future ❤️

Fabulous serum

It has such a wonderful texture that glides on to skin, not like other vitamin C serums which tend to be quite watery. It gave a smooth texture and I noticed much better hydration during the day. I'll definitely be buying more!

I enjoyed using this product

I enjoyed using this product. It felt very smooth on my skin and definitely seemed to reduce some of my pigmentation. It worked very well under my foundation. I enjoyed using it in the morning before the moisturiser. I would definitely recommend it.

I enjoyed using the Pro Helix C

I enjoyed using the Pro Helix C. I felt my skin was smooth and bright. It was incredibly easy to use and layered well under moisturiser and SPF.
I thoroughly recommend.

Impressed with Skin Diary. am so impressed with skin diary prodexcited to try the new vitamin c

I am so impressed with skin diary products and very excited to try the new vitamin c. This product is lovely to apply and didn’t irritate my skin like other similar products. I and others noticed a difference in my skin texture. Plus I know the robust science behind all products. Well done to Skin Diary.

Luxurious Skin Care

It’s an excellent product that feels beneficial for the skin.
Smoothing on with a non-cloying richness it provides an even base for moisturiser and foundation.

The texture & Glow

I have tried so many vitamin c serums & creams, either too tacky or never absorbed into my skin. I absolutely love the creamy texture of this vitamin c & the glow that it gives every morning. It sits well under my makeup too

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Pro-Helix C