Dr Dray Rebuffs Costly Vitamin C Serums on Thin Clinical Trial Data

Dr Dray

Topical vitamin C remains an optional luxury rather than a skincare essential because clinical trial outcomes are heavily confounded by routine sunscreen use, while low-pH formulas risk worsening hyperpigmentation through irritation.

AI-assisted summary of Do You Actually Need Vitamin C Serum? A Dermatologist Explains — original source. Check the original for full context.

Source published: 2026-08-17

Key ideas

The clinical evidence base for topical vitamin C is surprisingly limited: a 2023 systematic review evaluated only seven randomized controlled trials covering a total of 139 human participants across photoaging and melasma. (4:07)
Dramatic before-and-after results in clinical trials are heavily confounded by mandatory daily sunscreen use, obscuring how much visible improvement stems from the vitamin C serum versus consistent sun protection. (6:30)
Commonly marketed synthetic derivatives like THD ascorbate, MAP, and SAP lack robust clinical evidence proving they reliably penetrate human skin, convert into free ascorbic acid, and stimulate dermal collagen synthesis. (10:17)
Topical vitamin C is an optional adjunct rather than a skincare essential, ranking well behind proven dermatological cornerstones like daily broad-spectrum sunscreen and topical retinoids. (16:04)

Detailed notes

## Background Published on YouTube on August 17, 2026, by board-certified dermatologist Dr. Dray, this video examines whether topical vitamin C serum is truly necessary in an effective skincare routine. According to the page description, Dr. Dray explores the clinical science behind ascorbic acid, addressing its role in collagen synthesis, photoaging, and hyperpigmentation while critically assessing study limitations, formulation instability, skin irritation, and steep product costs.

## TL;DR While topical vitamin C operates as an antioxidant cofactor capable of stimulating collagen synthesis and inhibiting tyrosinase, its clinical evidence base remains surprisingly small compared to gold-standard dermatological actives like retinoids. Many positive study outcomes are confounded by concurrent daily sunscreen use or temporary optical hydration effects rather than dramatic dermal remodeling alone. Furthermore, pure ascorbic acid requires an acidic, low-pH environment that frequently triggers stinging, barrier disruption, or post-inflammatory hyperpigmentation, while marketed derivatives lack robust proof of active cutaneous conversion. Ultimately, Dr. Dray emphasizes that while vitamin C can serve as a viable alternative for those unable to tolerate retinoids or niacinamide, daily broad-spectrum sunscreen and proven fundamentals remain the true non-negotiables.

## Atmosphere & style Dr. Dray delivers an analytical, no-nonsense masterclass in evidence-based skincare skepticism, blending clinical rigor with dry, deadpan pragmatism. The narrative moves deliberately from biochemical plausibility to the messy realities of real-world clinical trials, systematically puncturing commercial hype and marketing buzzwords without ever becoming dismissive. Watching the discussion feels like a refreshing, grounded reality check from an unbothered medical professional who prioritizes skin barrier integrity and financial practicality over multi-step beauty routines.

## Bulletin - [04:07](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=247s) The clinical evidence base for topical vitamin C is surprisingly limited: a 2023 systematic review evaluated only seven randomized controlled trials covering a total of 139 human participants across photoaging and melasma. - [06:30](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=390s) Dramatic before-and-after results in clinical trials are heavily confounded by mandatory daily sunscreen use, obscuring how much visible improvement stems from the vitamin C serum versus consistent sun protection. - [10:17](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=617s) Commonly marketed synthetic derivatives like THD ascorbate, MAP, and SAP lack robust clinical evidence proving they reliably penetrate human skin, convert into free ascorbic acid, and stimulate dermal collagen synthesis. - [16:04](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=964s) Topical vitamin C is an optional adjunct rather than a skincare essential, ranking well behind proven dermatological cornerstones like daily broad-spectrum sunscreen and topical retinoids.

## Key takeaways - [00:00](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=0s) Ascorbic acid neutralizes reactive oxygen species generated by UV radiation and pollution, inhibiting the AP-1 transcription factor that upregulates collagen-degrading matrix metalloproteinases (MMPs). - [02:34](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=154s) Vitamin C functions as an indispensable enzymatic cofactor for collagen synthesis, with split-face biopsy studies confirming genuine histological neocollagenesis rather than mere temporary hydration. - [04:07](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=247s) A 2023 systematic review identified only seven randomized controlled trials encompassing 139 participants, indicating the overall clinical evidence base for topical vitamin C remains small. - [05:30](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=330s) Head-to-head clinical trials comparing topical vitamin C directly against dermatological gold standards like tretinoin or hydroquinone are virtually non-existent. - [05:30](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=330s) Topical retinoids and daily broad-spectrum sunscreen possess far stronger, systematic clinical evidence for reversing photoaging and preserving skin architecture than vitamin C. - [06:30](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=390s) Mandatory sunscreen application in vitamin C studies creates a major methodological confounder, as newly adopted sun habits significantly drive cosmetic improvements. - [06:30](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=390s) Hydration from a study vehicle can optically blur wrinkles and hyperpigmentation, causing improvements that are misattributed to active vitamin C without vehicle-controlled split-face verification. - [08:37](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=517s) Vitamin C helps manage hyperpigmentation by directly inhibiting tyrosinase, the rate-limiting enzyme in melanogenesis, though evidence is insufficient to rank it alongside hydroquinone. - [09:31](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=571s) Ascorbic acid works synergistically with vitamin E by reducing oxidized tocopherol radicals back into their active antioxidant state within skin lipid membranes. - [10:17](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=617s) Pure L-ascorbic acid requires an acidic low pH and is chemically unstable, oxidizing rapidly in the presence of air, light, and temperature fluctuations. - [10:17](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=617s) Synthetic vitamin C derivatives offer enhanced bottle stability, but cosmetics regulations do not require manufacturers to prove barrier penetration or biological collagen induction in vivo. - [13:43](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=823s) Low-pH vitamin C formulations frequently trigger stinging, erythema, and barrier irritation, which can paradoxically worsen post-inflammatory hyperpigmentation in melanin-rich skin. - [13:43](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=823s) Individuals with inflammatory skin conditions such as rosacea frequently experience intense flares and burning from acidic ascorbic acid serums. - [13:43](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=823s) Clinically evaluated patented serums cost upwards of $100 to $180, yet lack evidence proving meaningful clinical superiority over foundational, cost-effective skincare practices. - [16:04](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=964s) Vitamin C is not a mandatory routine step, but it serves as a reasonable antioxidant alternative for individuals who cannot tolerate retinoids or niacinamide.

## Detailed walkthrough ### [00:00](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=0s) What Does Vitamin C Actually Do?

Topical vitamin C serums have become a staple in modern skincare. Brands are practically expected to offer one, and consumers are constantly bombarded with claims about its ability to reverse aging, brighten dark spots, stimulate collagen, and smooth wrinkles. Dr. Dray notes that the most frequent inquiry she receives is simply whether anyone actually needs one. Chemically known as ascorbic acid, vitamin C is a water-soluble vitamin naturally present in the skin that serves as a cornerstone of the body's antioxidant defense network. Human skin is under continuous barrage from environmental stressors that drive oxidative stress, including ultraviolet (UV) radiation, atmospheric pollution, infrared radiation, and visible light. These stressors unleash free radicals, or reactive oxygen species (ROS)—unstable molecules that inflict direct damage on cellular proteins, lipids, and DNA. Vitamin C steps in as an electron donor, effectively neutralizing these volatile compounds before they can wreak havoc.

When UV rays penetrate the skin, the resulting burst of free radicals activates cellular cascades that upregulate matrix metalloproteinases (MMPs), enzymes notorious for breaking down existing collagen structures. Simultaneously, UV exposure impairs the synthesis of new, normal collagen while fostering the buildup of disorganized, abnormal elastin. Over decades, this destructive cycle surfaces as the hallmark signs of photoaging: deep wrinkles, rough textural irregularities, and an uneven complexion. In preclinical laboratory settings, vitamin C shows clear protective capability by disrupting these degradation pathways, specifically by blocking the activation of the transcription factor AP-1, which drives MMP production. However, Dr. Dray cautions against blind optimism: while cell cultures and small animal models demonstrate biological plausibility, promising lab findings often fail to replicate at the same magnitude in real-world human clinical trials. As she puts it, "it's important not to put all our eggs in those cell baskets."

```mermaid flowchart TD accTitle: UV Radiation to Photoaging Pathway accDescr: Diagram illustrating how UV exposure generates free radicals leading to collagen breakdown and how vitamin C intervenes.

subgraph Stressors["Environmental Exposure"] UV["UV Radiation & Pollution"] end

subgraph CellularEvents["Oxidative Cascade"] ROS["Reactive Oxygen Species (Free Radicals)"] AP1["AP-1 Transcription Factor"] MMP["Matrix Metalloproteinases (MMPs)"] end

subgraph Pathology["Skin Damage"] Breakdown["Collagen Breakdown & Abnormal Elastin"] Aging["Photoaging: Wrinkles, Roughness, Dark Spots"] end

VitC["Vitamin C (Antioxidant / Electron Donor)"]

UV --> ROS ROS --> AP1 AP1 --> MMP MMP --> Breakdown Breakdown --> Aging

VitC -.->|"Neutralizes"| ROS VitC -.->|"Inhibits Activation"| AP1 ```

[02:34](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=154s) Vitamin C and Collagen Production

Beyond scavenging oxidative species, vitamin C serves as an indispensable enzymatic cofactor required for synthesizing and structurally stabilizing new collagen triple helices. It can modulate gene expression involved in procollagen synthesis while dampening the downstream processes that actively destroy structural proteins. Clinical trials in human subjects do provide measurable validation for these mechanisms. Multiple randomized controlled trials demonstrate that applying topical vitamin C over several months visibly softens fine lines, smooths coarse texture, and diminishes signs of photoaging.

Crucially, this improvement is not merely a superficial optical illusion created by temporary hydration. A small, double-blind, split-face clinical trial utilizing a 10% topical vitamin C formulation evaluated tissue changes via skin biopsy. The histology revealed objective histological proof of newly synthesized, healthy collagen fibers replacing UV-damaged matrix tissue. This demonstrates that topical vitamin C can stimulate true dermal remodeling rather than merely "moisturizing the skin to make wrinkles appear less obvious."

[04:07](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=247s) How Good Is the Evidence for Topical Vitamin C?

Despite these promising findings, Dr. Dray challenges the prevailing narrative that the ingredient is an unequivocal, non-negotiable miracle. When scrutinized closely, the clinical evidence base is surprisingly sparse, leading to an overhyped reputation that may not justify consumer price tags reaching $100 to $125 per bottle. A 2023 systematic review examining randomized controlled trials of topical vitamin C for photoaging and melasma uncovered a stark reality: only seven publications met the inclusion criteria, encompassing a combined total of merely 139 human participants.

While that review acknowledged general improvements in skin texture, wrinkling, and pigmentation, the authors concluded that higher-quality research is mandatory before dermatologists can pinpoint the exact degree of clinical efficacy, optimal concentration, or best delivery formulation. While encouraging, the body of literature is far from expansive, leaving major gaps concerning what standard of benefit consumers should realistically expect.

[05:30](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=330s) Vitamin C vs. More Established Skincare Ingredients

A major limitation of the current research is the near-total lack of head-to-head clinical trials pitting vitamin C against recognized, gold-standard dermatological actives. When people ask search engines whether vitamin C outperforms tretinoin for anti-aging, or whether it rivals hydroquinone for hyperpigmentation, the scientific literature provides no comparative data. An ingredient demonstrating superiority over an inactive vehicle or placebo cream in a limited trial proves only that it has some biological effect; it does not automatically make it a clinical first choice or a "must-have" routine item.

For individuals seeking true, rigorous anti-aging evidence, topical retinoids stand on a far sturdier foundation. Systematic reviews of photoaged skin treatments consistently label prescription retinoids as the most evidence-based and potent topical agents available, despite potential side effects like dryness and retinoid dermatitis. Furthermore, a 2025 network meta-analysis reinforced that both prescription tretinoin and over-the-counter retinol hold the strongest statistical backing for reversing fine wrinkles and stubborn discoloration. For patients navigating limited time, constrained budgets, or sensitive skin that cannot tolerate multi-step regimens, Dr. Dray does not recommend reaching for a vitamin C serum first. Instead, she advises anchoring the routine around the single intervention backed by the strongest preventive and restorative evidence in all of dermatology: daily, broad-spectrum sunscreen.

[06:30](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=390s) The Sunscreen Problem in Vitamin C Studies

Evaluating clinical trials on vitamin C reveals a major methodological confounder: the mandatory integration of sunscreen. In photoaging and pigmentation studies, trial protocols routinely provide participants with a sunscreen and mandate daily application to control confounding UV exposure during the study period. While scientifically reasonable from an experimental standpoint, this introduces a major variable when interpreting before-and-after photographs.

Many trial participants enter studies with chronic, untreated photodamage and poor baseline sun habits. Once enrolled, they start the experimental vitamin C serum while simultaneously adopting meticulous, daily sunscreen use simply because they were handed a bottle and instructed to use it. When these subjects show dramatic cosmetic improvement months later, determining how much progress stems from the vitamin C serum versus the newfound, rigorous sun protection becomes virtually impossible.

- **The Split-Face Ideal:** Disentangling this effect requires rigorous split-face designs where sunscreen is applied across the entire face while the active vitamin C serum is isolated to one half and an identical vehicle placebo to the other. - **Methodological Flaws in Modern Studies:** Many newer trials abandon this rigor entirely, utilizing open-label designs or lacking placebo controls altogether. - **The Hydration Confounder:** Even an inert moisturizing base increases epidermal water content; this hydration alters optical light scattering on the skin surface, making wrinkles and dark spots appear visibly softer without altering underlying pathology.

[08:37](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=517s) Vitamin C for Dark Spots and Hyperpigmentation

Beyond its anti-aging claims, vitamin C possesses a direct, biochemically verified mechanism for managing irregular skin pigmentation. Hyperpigmentation presents across various clinical contexts, ranging from solar lentigines associated with photoaging to stubborn conditions like post-inflammatory hyperpigmentation (PIH) and melasma. Vitamin C exerts its depigmenting action by directly inhibiting tyrosinase, the rate-limiting copper-containing enzyme required within melanocytes to synthesize melanin pigment.

[09:00](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=540s) Vitamin C for Hyperpigmentation and Synergy with Vitamin E

Topical vitamin C directly affects melanin production by inhibiting tyrosinase, the rate-limiting enzyme in pigment formation. Theoretically, reducing tyrosinase activity translates to lower melanin output, and clinical studies do support a depigmenting effect. Systematic reviews demonstrate statistically significant skin lightening in certain study cohorts. However, whether that justifies placing vitamin C in the same therapeutic tier as hydroquinone remains questionable. Skincare incorporates several other tyrosinase inhibitors, and there is a distinct lack of robust head-to-head clinical trials evaluating topical ascorbic acid directly against those alternatives. Ultimately, it serves as a viable option for uneven tone, but it remains far from an indispensable requirement.

Beyond pigment pathways, vitamin C exhibits a compelling biochemical relationship with vitamin E (tocopherol). Vitamin E resides naturally within the skin to safeguard barrier lipids against oxidative degradation. When vitamin E neutralizes a free radical, it becomes oxidized; topical vitamin C can step in and chemically regenerate that spent vitamin E back into its active antioxidant state. This biological cooperation provides the rationale behind classic trios featuring vitamin C, vitamin E, and ferulic acid, where the ingredients "not only help your skin, but they help each other out." Nevertheless, mechanistic plausibility in a laboratory does not guarantee that slathering an antioxidant cocktail onto the skin will dramatically raise physiological cutaneous vitamin E reserves in daily life.

- **Tyrosinase Inhibition:** Clinical trials validate mild-to-moderate depigmenting outcomes, though hydroquinone remains the medical benchmark for stubborn hyperpigmentation. - **Antioxidant Recycling:** Ascorbic acid reduces oxidized vitamin E radicals, protecting lipid peroxidation in the stratum corneum and cell membranes. - **Compound Synergies:** The combination of L-ascorbic acid, alpha-tocopherol, and ferulic acid stabilizes the solution and provides additive photoprotective benefits compared to monotherapies.

---

[10:17](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=617s) Formulation Challenges and the "La-Di-Da" Derivatives

Formulating topical vitamin C is notoriously difficult because pure L-ascorbic acid is inherently unstable and struggles to penetrate the cutaneous stratum corneum. It oxidizes rapidly upon exposure to air, light, and fluctuating temperatures. Even if a brand advertises a high percentage on the packaging, that number does not guarantee that a biologically meaningful concentration survives or crosses the skin barrier intact. To sidestep these instability headaches, cosmetic manufacturers frequently turn to synthetic alternatives that Dr. Dray jokingly dubs the "lottie dottie derivatives"—compounds prominently marketed as "Vitamin C Serum" on the front label despite containing no pure ascorbic acid at all.

Common derivatives include magnesium ascorbyl phosphate (MAP), sodium ascorbyl phosphate (SAP), ascorbyl glucoside, and tetrahexyldecyl ascorbate (THD ascorbate). While marketed aggressively as "a highly stable form of vitamin C," head-to-head independent research on these molecules is sparse. Crucially, solid clinical evidence is lacking to prove that these derivatives reliably penetrate human skin in vivo, undergo enzymatic cleavage to liberate free ascorbic acid, or stimulate de novo dermal collagen synthesis. While they may provide superficial antioxidant protection against environmental oxidative stress at the skin's surface, consumers targeting photoaging, fine lines, and collagen preservation must seek out true ascorbic acid—while recognizing that cosmetics manufacturers are under no regulatory obligation to prove their finished formulas actually deliver active ingredients to living dermal tissue.

```mermaid flowchart TD accTitle: Topical Vitamin C Pathway Comparison accDescr: Flowchart illustrating the differences in skin penetration and collagen synthesis between pure ascorbic acid and synthetic vitamin C derivatives.

subgraph Pure ["Ascorbic Acid (Pure Vitamin C)"] A["L-Ascorbic Acid"] -->|"Prone to rapid oxidation"| B["Oxidation Risk: Light & Air"] A -->|"Formulation Hurdle: Low pH required"| C["Penetrates Skin Barrier"] C --> D["Directly Stimulates Collagen Synthesis"] end

subgraph Deriv ["Synthetic Vitamin C Derivatives"] E["Derivatives: MAP, SAP, THD, Glucoside"] -->|"Chemically modified"| F["Highly Stable in Bottle"] E -->|"Unknown rate of absorption"| G["Questionable Barrier Penetration"] G -->|"Must cleave into free ascorbic acid"| H["Unproven Conversion & Collagen Impact"] end ```

- **Ascorbic Acid vs. Derivatives:** Pure ascorbic acid is bioactive upon absorption, whereas derivatives require enzymatic conversion steps inside viable tissue that remain largely unproven in humans. - **Popular Derivatives on Labels:** Magnesium ascorbyl phosphate, sodium ascorbyl phosphate, ascorbyl glucoside, and tetrahexyldecyl ascorbate. - **The Cosmetic Reality:** Because these products are regulated as cosmetics rather than prescription drugs, brands are never required to prove therapeutic tissue penetration or physiological collagen induction.

---

[13:43](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=823s) Downsides: Skin Irritation, Hyperpigmentation Risk, and Steep Costs

The most prominent adverse effect of topical ascorbic acid is cutaneous irritation, presenting as acute burning, stinging, erythema, and dryness due to the low, acidic pH required to keep the molecule stable and bioavailable. This irritation carries serious clinical consequences for individuals with skin of color. In melanin-rich complexions prone to post-inflammatory hyperpigmentation (PIH), persistent micro-irritation from aggressive actives will directly trigger melanocytes to deposit excess pigment, causing dark spots to become darker, broader, and far more stubborn. As Dr. Dray cautions, "if it's not broken in your skincare routine, do you really need to go attempting to fix it, especially if you are vulnerable to stubborn hyperpigmentation?" A product introduced to lighten spots can easily backfire and worsen the exact problem being treated.

Underlying inflammatory conditions like rosacea present another major barrier, as acidic serums frequently provoke intense flushing and inflammatory flares. While rosacea does not represent an absolute contraindication, forcing the skin to endure irritation is counterproductive: "Please do not persevere through that aggravating your rosacea." Beyond tolerability, financial cost remains a massive deterrent. Clinically studied benchmarks—such as the patented SkinCeuticals C E Ferulic or the Cellex-C serum evaluated in smaller trials published in *JAMA Otolaryngology*—range from $100 to well over $120 to $180 per bottle. While higher price tags may fund patented stabilization methods and published testing, they remain cost-prohibitive, and compelling evidence demonstrating absolute superiority over affordable basics does not exist.

- **Post-Inflammatory Hyperpigmentation:** Irritation from low-pH serums directly stimulates reactive melanogenesis, worsening dark spots in deeper Fitzpatrick phototypes. - **Rosacea Flares:** Compromised barrier function in rosacea patients leaves them prone to severe stinging, sustained erythema, and barrier impairment from pure ascorbic acid. - **Clinical Study Formulations:** Landmark peer-reviewed trials often evaluate premium patented preparations (e.g., Cellex-C, SkinCeuticals C E Ferulic), making it difficult to extrapolate those clinical results to generic drugstore serums.

---

[16:04](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=964s) Does Anyone Actually Need Vitamin C? Core Priorities and Personal Choice

When evaluating skincare interventions on a strictly evidence-based hierarchy for photoaging, dyschromia, texture, and UV-induced damage, vitamin C ranks well below the true non-negotiable fundamentals. Daily broad-spectrum sunscreen stands unmatched as the single most critical preventative and therapeutic topical, followed immediately by topical retinoids (such as prescription tretinoin or over-the-counter retinol and retinaldehyde). Sunscreen and retinoids together provide the overwhelming majority of documented anti-aging and pigment-regulating benefits. Vitamin C serves as an optional adjunct rather than an essential cornerstone.

Dr. Dray confirms that she personally does not maintain a vitamin C serum in her everyday routine, relying instead on well-formulated sunscreens, retinoids, and widespread multi-taskers like niacinamide, which delivers visible benefits and naturally appears across countless formulations. However, for consumers who cannot physically tolerate topical retinoids or who experience sensitivity to niacinamide, exploring an ascorbic acid serum makes practical sense as an alternative antioxidant. Skincare routines need not mirror internet trends: if a product is financially draining, provokes burning, or overcomplicates daily regimens, skipping it entirely will not compromise skin health.

- **Hierarchy of Evidence:** Daily broad-spectrum sunscreen is the primary preventive shield, with topical retinoids serving as the clinical gold standard for cellular turnover and neocollagenesis. - **Who Should Consider It:** Individuals seeking daytime environmental antioxidant defense who cannot tolerate retinoids or experience adverse flushing/irritation from niacinamide. - **Core Recommendation:** Vitamin C is "not a must-have for everyone"—prioritize consistent photoprotection, gentle barrier support, and clinically proven fundamentals over expensive cosmetic serums.

## Notable quotes > [00:00](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=0s) it's important not to put all our eggs in those cell baskets. — Dr. Dray

> [02:34](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=154s) moisturizing the skin to make wrinkles appear less obvious. — Dr. Dray

> [09:00](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=540s) not only help your skin, but they help each other out. — Dr. Dray

> [10:17](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=617s) lottie dottie derivatives — Dr. Dray

> [10:17](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=617s) a highly stable form of vitamin C

> [13:43](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=823s) if it's not broken in your skincare routine, do you really need to go attempting to fix it, especially if you are vulnerable to stubborn hyperpigmentation? — Dr. Dray

> [13:43](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=823s) Please do not persevere through that aggravating your rosacea. — Dr. Dray

> [16:04](https://www.youtube.com/watch?v=WQrwaOFMEzc&t=964s) not a must-have for everyone — Dr. Dray

## Mentioned Dr. Dray, SkinCeuticals C E Ferulic, Cellex-C, JAMA Otolaryngology

## Video description Dermatologist Dr. Dray breaks down the science behind topical vitamin C, including what vitamin C does for the skin, how it may help with wrinkles, collagen production, photoaging, dark spots, and hyperpigmentation, and whether a vitamin C serum is actually necessary for an effective skincare routine.

Vitamin C, also known as ascorbic acid, is a powerful antioxidant that can help neutralize free radicals generated by UV radiation, pollution, and other environmental exposures. It also plays an important role in collagen synthesis and may help reduce melanin production, making it an interesting ingredient for both anti-aging skincare and hyperpigmentation.

But how strong is the clinical evidence? And is vitamin C actually better than ingredients like tretinoin, retinoids, niacinamide, hydroquinone, or sunscreen?

Dr. Dray discusses the research, the limitations of vitamin C studies, the importance of formulation and stability, potential skin irritation, and whether expensive vitamin C serums are worth the money.

In this video:

0:00 Introduction 0:36 What does vitamin C actually do? 2:34 Vitamin C and collagen production 4:07 How good is the evidence for topical vitamin C? 5:30 Vitamin C vs. more established skincare ingredients 6:30 The sunscreen problem in vitamin C studies 8:37 Vitamin C for dark spots and hyperpigmentation 9:31 Vitamin C and vitamin E 10:17 Why vitamin C formulation and stability matter 13:43 Downsides of topical vitamin C: irritation and cost 16:04 Does anyone actually need vitamin C? 16:38 Final thoughts

Vitamin C for skin: the bottom line

Topical vitamin C is not a scam, but it is also not a mandatory step in everyone's skincare routine.

Clinical research supports potential benefits for photoaging, fine lines, wrinkles, skin texture, and hyperpigmentation, but the overall evidence base is still relatively limited. Studies use different concentrations, formulations, and delivery systems, making it difficult to determine exactly which vitamin C product or derivative is best.

Vitamin C can also be challenging to formulate because pure ascorbic acid is unstable, and higher concentrations may cause stinging, dryness, redness, or irritation.

For someone building an evidence-based skincare routine, Dr. Dray emphasizes prioritizing proven fundamentals, particularly daily sunscreen and, when appropriate, topical retinoids. Vitamin C can be a useful addition, but it does not need to be included simply because it is popular.

The video also discusses why dramatic before-and-after photos from vitamin C studies should be interpreted carefully, particularly when study participants are also instructed to use sunscreen consistently.

Key topics: vitamin C serum, vitamin C skincare, vitamin C for skin, ascorbic acid, topical vitamin C, vitamin C for wrinkles, vitamin C for dark spots, vitamin C for hyperpigmentation, vitamin C for anti-aging, vitamin C and collagen, vitamin C antioxidant, vitamin C vs retinol, vitamin C vs tretinoin, vitamin C vs niacinamide, vitamin C vs hydroquinone, vitamin C and sunscreen, best vitamin C serum, vitamin C irritation, vitamin C serum benefits, vitamin C serum side effects, does vitamin C actually work, dermatologist vitamin C review, evidence based skincare, anti-aging skincare, skincare ingredients.

Disclaimer: This video is for educational purposes and is not a substitute for individualized medical advice or treatment from a qualified healthcare professional.

FTC: This video is not sponsored. Links are commissionable, meaning I may earn commission from purchases made through links.

💜Shop my Amazon store https://o.bttn.io/0BwiPWFIZLG 💜Follow me on liketoknowit https://www.liketoknow.it/drdrayzday 💜Social media Instagram @drdrayzday Pinterest https://www.pinterest.com/drdrayzday/ Facebook @DrDrayzDay Twitter: @drdrayzday Tiktok: @drdrayzday

Disclaimer: This video is not intended to provide diagnosis, treatment or medical advice. Content provided on this Youtube channel is for informational purposes only. Please consult with a physician or other healthcare professional regarding any medical or health related diagnosis or treatment options. Information on this Youtube channel should not be considered as a substitute for advice from a healthcare professional. The statements made about specific products throughout this video are not to diagnose, treat, cure or prevent disease.

[Source](https://www.youtube.com/watch?v=WQrwaOFMEzc)

中文简报

临床试验数据薄弱，Dr Dray对昂贵的维生素C精华提出质疑外用维生素C仍属于可选的奢华步骤而非护肤必需品，因为临床试验结果在很大程度上受到常规防晒霜使用的混淆，而低pH值配方还存在因刺激而加重色素沉着的风险。尽管外用维生素C作为一种抗氧化辅助因子能够刺激胶原蛋白合成并抑制酪氨酸酶，但与维A类等皮肤学黄金标准活性成分相比，其临床证据基础仍然少得惊人。许多积极的研究结果都受到了同时每日使用防晒霜或暂时性视觉保湿效果的混淆，而非单纯来自显著的真皮重塑。此外，纯抗坏血酸需要酸性、低pH值的环境，这往往会引发刺痛、屏障受损或炎症后色素沉着，而市售的衍生物则缺乏在皮肤内有效转化的有力证据。归根结底，Dr. Dray强调，尽管维生素C可以作为无法耐受维A类或烟酰胺人群的可行替代品，但每日广谱防晒和经过验证的基础护肤依然是真正不可或缺的核心。外用维生素C的临床证据基础出人意料地有限：一项2023年的系统评价仅评估了七项随机对照试验，涵盖光老化和黄褐斑领域的总受试者仅139人。 (4:07) 临床试验中显著的改善前后对比受到强制性每日使用防晒霜的严重混淆，导致无法分清肉眼可见的改善究竟有多少归功于维生素C精华，又有多少源于坚持防晒。 (6:30) 市面上常见的合成衍生物（如THD抗坏血酸酯、MAP和SAP）缺乏可靠的临床证据，来证明它们能有效渗透人体皮肤、转化为游离抗坏血酸并刺激真皮胶原蛋白合成。 (10:17) 外用维生素C是一种可选的辅助成分，而非护肤必需品，其重要性远落后于每日广谱防晒霜和外用维A类等经过验证的皮肤学基石。 (16:04)

Reading summary

Dermatologist Dr. Dray explains that while topical vitamin C possesses verified biological antioxidant and collagen-building mechanisms, its clinical evidence base remains surprisingly limited and prone to study confounders. Rather than being an indispensable skincare staple, she positions it as an optional adjunct outranked by daily sunscreen and topical retinoids. Biological Mechanisms and Direct Dermal Remodeling (0:00) Vitamin C (ascorbic acid) functions as a water-soluble electron donor that neutralizes reactive oxygen species generated by ultraviolet radiation and environmental pollution. Preclinical models indicate that it inhibits the transcription factor AP-1, dampening the production of matrix metalloproteinases (MMPs) that break down collagen. Beyond oxidative defense, it acts as an enzymatic cofactor required to synthesize and structurally stabilize collagen triple helices. Clinical evidence includes a double-blind, split-face trial of a 10% formulation that confirmed objective histological proof of newly synthesized collagen replacing photodamaged tissue, demonstrating true dermal remodeling rather than superficial optical smoothing. In addition to structural support, ascorbic acid directly inhibits tyrosinase, the rate-limiting copper enzyme required for melanogenesis, providing biological backing for treating hyperpigmentation, melasma, and solar lentigines. It also exhibits synergy with cutaneous vitamin E by donating electrons to regenerate oxidized tocopherol back into its active antioxidant state, protecting lipid membranes against peroxidation. Sparse Clinical Evidence and Study Confounders (4:07) Despite aggressive marketing claims, Dr. Dray emphasizes that the published evidence supporting vitamin C is far narrower than consumer perception suggests. A 2023 systematic review evaluating randomized controlled trials for photoaging and melasma uncovered only seven publications meeting inclusion criteria, encompassing a combined total of merely 139 human participants. Furthermore, the literature lacks head-to-head clinical trials evaluating ascorbic acid directly against dermatological gold standards such as prescription tretinoin for anti-aging or hydroquinone for hyperpigmentation. Interpreting published efficacy is further complicated by experimental design flaws. Clinical protocols routinely supply participants with broad-spectrum sunscreen and mandate daily use. When subjects with poor baseline sun habits exhibit dramatic cosmetic improvements over several months, isolating the effect of the vitamin C serum from the sudden introduction of rigorous UV protection becomes virtually impossible. Additionally, open-label designs and inert moisturizing bases increase epidermal hydration, altering surface light scattering to make fine lines appear diminished without rectifying underlying pathology. Formulation Stability and Synthetic Derivative Limitations (10:17) Pure L-ascorbic acid presents severe formulation challenges due to its rapid oxidation upon exposure to air, light, and temperature changes, alongside requiring an acidic pH to penetrate the stratum corneum. In response, cosmetics manufacturers frequently turn to synthetic derivatives such as magnesium ascorbyl phosphate (MAP), sodium ascorbyl phosphate (SAP), ascorbyl glucoside, and tetrahexyldecyl ascorbate (THD ascorbate). Although heavily marketed for superior chemical stability in the bottle, Dr. Dray notes that these derivatives lack robust, independent clinical evidence proving they reliably penetrate human skin in vivo, undergo enzymatic cleavage to release active ascorbic acid, or induce collagen synthesis. Because these formulations are regulated as cosmetics rather than pharmaceuticals, manufacturers are under no regulatory obligation to demonstrate that their products deliver active molecules to living dermal tissue. Irritation Risks, Steep Costs, and Hierarchy (13:43) The low pH required to stabilize bioavailable ascorbic acid frequently provokes cutaneous burning, stinging, erythema, and dryness. In deeper skin phototypes, persistent micro-irritation risks activating melanocytes to induce post-inflammatory hyperpigmentation (PIH), worsening the dark spots the user intended to treat. The acidic profile can also provoke intense flushing in patients with rosacea. These tolerability hurdles are compounded by steep price tags, with benchmark, patented formulations often retailing between $100 and $180 per bottle without clinical proof of clear superiority over basic regimens. When organizing an evidence-based routine, Dr. Dray emphasizes that daily broad-spectrum sunscreen remains the single most critical preventive and therapeutic intervention, followed by topical retinoids. A 2025 network meta-analysis reinforced that prescription tretinoin and over-the-counter retinol hold the strongest statistical evidence for reversing fine wrinkles and discoloration. Dr. Dray does not include a vitamin C serum in her own regimen, recommending it primarily as a daytime antioxidant alternative for individuals unable to tolerate retinoids or multi-taskers like niacinamide. Topical vitamin C offers established biochemical antioxidant activity, but high product costs, formulation instability, irritation risks, and a small clinical trial footprint prevent it from being a mandatory skincare step. Higher-quality, split-face comparative trials remain necessary to establish optimal concentrations, delivery systems, and real-world efficacy relative to standard dermatological therapies.

Source quotes

[0:00] Dr. Dray: it's important not to put all our eggs in those cell baskets. [2:34] Dr. Dray: moisturizing the skin to make wrinkles appear less obvious. [9:00] Dr. Dray: not only help your skin, but they help each other out. [10:17] Dr. Dray: lottie dottie derivatives [10:17] a highly stable form of vitamin C [13:43] Dr. Dray: if it's not broken in your skincare routine, do you really need to go attempting to fix it, especially if you are vulnerable to stubborn hyperpigmentation? [13:43] Dr. Dray: Please do not persevere through that aggravating your rosacea. [16:04] Dr. Dray: not a must-have for everyone

Original transcript

[0:00] Well, hey guys. Welcome back. If you're [0:01] new here, I'm Dr. Dray. I'm a [0:03] board-certified dermatologist. And in [0:05] today's video, I want to get into the [0:07] nitty-gritty details of vitamin C [0:09] serums. It's no secret, they're popular. [0:11] You hear them touted for anti-aging, [0:13] dark spots, improving collagen, [0:16] smoothing out wrinkles, and targeting [0:18] unwanted pigmentation. They're arguably [0:20] one of the most popular skin care [0:23] products. In fact, if you're a skin care [0:25] brand, be prepared. You're almost [0:27] expected to offer a vitamin C serum. And [0:30] one of the most common questions I get [0:32] is, do I need a vitamin C serum? So, [0:35] we're going to tackle that in today's [0:36] video. Vitamin C, also called ascorbic [0:38] acid, is a water-soluble vitamin [0:41] naturally present in your skin. One of [0:42] the most important functions of vitamin [0:44] C is as an antioxidant. Our skin is [0:46] constantly exposed to things that [0:48] generate a lot of oxidative stress. UV [0:50] radiation, of course, is a major one, [0:52] but there's also pollution, infrared [0:54] radiation, and visible light. And these [0:56] exposures generate free radicals, [0:59] sometimes referred to as reactive oxygen [1:00] species. These are unstable molecules, [1:02] and they damage proteins, lipids, and [1:04] DNA in our skin. Vitamin C is an asset [1:07] here because it can donate electrons to [1:09] these molecules to neutralize them. In [1:11] other words, you can think of vitamin C [1:12] as really just part of your skin's [1:14] antioxidant defense system. It's not the [1:16] only one, but it's definitely a major [1:18] player. When UV radiation, for example, [1:20] hits the skin and generates free [1:22] radicals, these reactive oxygen species [1:25] stimulate signaling pathways that lead [1:27] to the upregulation of something called [1:29] matrix metalloproteinases. These are [1:31] enzymes in the skin that break down our [1:33] collagen. UV exposure also interferes [1:35] with normal collagen production and [1:37] leads to accumulation of abnormal [1:39] elastin. Over many years, this is what [1:41] contributes to the formation of [1:42] wrinkles, rough skin texture, and uneven [1:45] skin tone. These are all the visible [1:46] signs of, well, sun damage, aka [1:48] photoaging. Vitamin C is of interest [1:50] because in laboratory studies, it's been [1:52] shown to step in and interfere with some [1:55] of these damaging pathways. This [1:57] includes inhibiting the activation of [1:59] something known as AP-1, which is [2:01] involved in the upregulation of matrix [2:03] metalloproteinase enzymes. So, there's a [2:05] reasonable biological pathway mechanism [2:08] behind how vitamin C applied topically [2:10] might really help your skin out. [2:11] Unfortunately, biological mechanism [2:14] revealed from studying cells in a dish [2:16] and small animal models doesn't always [2:18] bear out to yield the results we were [2:20] quite expecting or hoping for when we [2:22] end up using these things in human [2:24] clinical trials. So, while early [2:26] laboratory-based studies are always [2:28] exciting and promising, it's important [2:30] not to put all our eggs in those cell [2:33] baskets, if you will. Vitamin C is also [2:36] vital for healthy collagen production. [2:38] It's a cofactor involved in the enzymes [2:40] needed to form and stabilize collagen. [2:43] And it can influence the expression of [2:45] genes involved in the formation of [2:47] collagen. And it can actively reduce [2:49] processes that directly degrade [2:51] collagen. All of these things sound [2:53] really good for having any anti- aging [2:55] benefit. And we actually do have [2:56] clinical studies on human beings that [2:58] show, yes, topical vitamin C can improve [3:01] the signs of skin aging. For example, [3:03] randomized controlled studies have shown [3:05] that topical vitamin C can in fact [3:07] improve the wrinkles and uneven skin [3:10] texture of aging skin over several [3:12] months. A small double-blind split-face [3:14] study using a 10% vitamin C formulation [3:17] showed that, yes, in fact, topical [3:20] application of vitamin C not only [3:21] improved the visible signs of skin [3:23] aging, but when they went and looked on [3:25] biopsy, there was evidence of improved [3:27] collagen production. In other words, [3:29] topical vitamin C doesn't just work by, [3:31] well, moisturizing the skin to make [3:33] wrinkles appear less obvious. It [3:35] actually replaces some of the lost [3:37] damaged collagen with new healthy [3:38] collagen to diminish those existing [3:40] wrinkles. It's easy to assume, "Oh, yep, [3:42] that proves it all." But does it really? [3:45] I mean, a few small scattered clinical [3:47] studies here and there helps to build a [3:49] case for the use of vitamin C, but it [3:51] doesn't really give us the kind of data [3:54] that we need to say, yes, this is going [3:55] to be worth it for people to spend $100 [3:58] and $125 on. It's important to take a [4:00] look at how good the evidence actually [4:02] is. And in fact, this is where I think [4:04] that vitamin C gets a little bit too [4:06] overhyped. A 2023 systematic review [4:09] specifically looked at randomized [4:10] controlled trials of topical vitamin C [4:13] for photoaging as well as melasma. They [4:15] found only seven eligible publications [4:17] involving 139 volunteers. generally [4:20] found improvements in wrinkles and skin [4:22] texture as well as pigmentation, but the [4:24] researchers concluded that more research [4:26] was needed in order to determine the [4:29] actual degree of benefit and the proper [4:32] concentration and overall formulation. [4:34] So yeah, the evidence is encouraging, [4:36] but I wouldn't say that the evidence [4:38] base is enormous. Also, we don't have [4:40] good clinical studies comparing vitamin [4:43] C to other established anti-aging [4:46] ingredients like topical retinoids, [4:48] sunscreen, or other fairly [4:50] well-established cosmetic ingredients [4:52] like niacinamide for things like dark [4:54] spots. So when someone says vitamin C is [4:56] a must-have, is it really? I mean, how [4:59] does it stack up compared to some of [5:00] these other ingredients? So if you find [5:02] yourself typing into Google, is vitamin [5:04] C better than tretinoin? Honestly, we [5:07] don't have any studies to answer that [5:09] question. For hyperpigmentation, how [5:10] does it stack up with the gold standard [5:12] hydroquinone? The reason this matters is [5:14] that an ingredient can have evidence for [5:16] being better than placebo, but that [5:18] doesn't necessarily make it the best [5:20] choice or a must-have ingredient. Like [5:22] better than well, just putting cream on [5:24] your face. Okay, that builds a case that [5:26] it does something for some people, at [5:29] least the people who were being studied. [5:31] When we're talking about ingredients to [5:32] improve the visible signs of skin aging, [5:35] topical retinoids have arguably the most [5:38] research backing them up. A review of [5:39] topical treatments for photoaged skin [5:41] describes topical prescription retinoids [5:44] as the most evidence-based and [5:46] efficacious topicals for improving aging [5:48] skin. However, irritation can be a [5:50] limitation. A 2025 network meta-analysis [5:53] also found pretty strong evidence for [5:55] topical retinoids for improving [5:57] photoaging. This includes prescription [5:59] tretinoin and retinol, namely for fine [6:01] wrinkles and hyperpigmentation. It [6:02] doesn't mean that vitamin C doesn't [6:04] work. In other words, if someone were to [6:06] ask me, "What is the best ingredient for [6:09] anti-aging that I could put on my skin?" [6:11] I'm probably not going to say vitamin C. [6:13] If someone has limited time, they're on [6:15] a tight budget, or their skin is just [6:17] not that tolerant to using different [6:19] ingredients, many products, I would not [6:22] guide them towards a vitamin C serum per [6:24] se. Instead, I would say prioritize the [6:26] things that have the most evidence. And [6:28] you want to know what that is? Yeah, [6:30] it's sunscreen. Speaking of sunscreen, [6:32] let's talk about the sunscreen problem [6:34] in vitamin C serums, cuz it's another [6:36] really interesting limitation when you [6:38] actually critically look at the vitamin [6:40] C serum studies. And you really take a [6:43] look at their methodologies, because [6:45] some clinical studies evaluating [6:47] photoaging include the use of sunscreen. [6:49] Like, they actively require the [6:51] participants to use a sunscreen, and [6:54] they not only require them to, but they [6:56] give them one. And that makes sense [6:58] scientifically. If you're conducting a [6:59] study on the benefits of a topical for [7:01] pigmentation or for photoaging, you're [7:04] going to want to control UV exposure [7:06] throughout the study as much as [7:07] possible. But it creates an interesting [7:08] issue if you look at the before and [7:10] after photos that they show in some of [7:12] these clinical studies. They look pretty [7:14] impressive, especially with regards to [7:15] overall skin tone. Well, let's say [7:17] someone enters the study with sun [7:19] damage, as is often the case. They start [7:22] using the vitamin C serum, but at the [7:24] same time, they're also now being much [7:26] more diligent about wearing sunscreen, [7:28] because, well, they've been given one, [7:30] and they're required to use it. So, if [7:32] their skin is looking dramatically [7:33] better several months later, how much of [7:35] that is due to the vitamin C alone [7:38] versus the now regular use of sun [7:42] protection, which has the most evidence [7:44] backing up its use. Now, a well-designed [7:46] placebo-controlled study can really help [7:48] to get at this question of whether or [7:50] not it's the sun protection versus the [7:52] vitamin C, particularly when you are [7:54] looking at an individual who just [7:56] applies vitamin C to one half of the [7:58] face but puts the sunscreen on both [8:00] sides, and you compare the two sides at [8:02] the end. But, unfortunately, not every [8:04] vitamin C study is designed this way. [8:06] Some newer studies are open-label, or [8:08] even worse, they don't have a placebo [8:10] control, which really a dilemma because, [8:13] as I pointed out before, simply [8:14] moisturizing the skin can improve the [8:16] overall look of the skin, including the [8:18] appearance of dark spots, through the [8:19] improvement of water content in the [8:21] skin, which, through light scattering, [8:22] makes those dark spots look a little [8:24] less obvious. This is why it's important [8:26] to always look beyond the abstract, [8:28] beyond the before-and-after photographs, [8:30] and really take a critical look at the [8:31] methodologies used, and decide for [8:33] yourself, are the results really that [8:35] compelling in light of how this was [8:37] done? Beyond simply improving the [8:38] appearance of aging skin, though, [8:40] vitamin C has a legitimate mechanism for [8:42] improving the appearance of unwanted [8:44] pigmentation, which, yes, can occur as [8:46] part of the aging process, but also [8:48] secondary to a variety of other things, [8:50] like, namely, post-inflammatory [8:51] hyperpigmentation, a hyperpigmentation [8:53] disorder, melasma. Vitamin C works by [8:56] inhibiting the enzyme tyrosinase, which [8:58] is necessary for melanin pigment [9:00] production. Theoretically, less [9:01] tyrosinase activity means less melanin [9:04] production. And clinical studies do, in [9:06] fact, support a depigmenting effect with [9:08] the use of topical vitamin C. The [9:10] systematic review I mentioned earlier [9:11] did show significant skin lightening [9:13] with topical vitamin C in some of the [9:15] studies. Is that enough to really put it [9:17] in the same category as hydroquinone? We [9:20] also have other ingredients that inhibit [9:21] tyrosinase, and we don't have good [9:24] studies comparing topical vitamin C [9:26] versus these other tyrosinase [9:27] inhibitors. In other words, vitamin C is [9:29] an option, but it's not necessarily a [9:31] must-have. Another reason why vitamin C [9:33] is interesting is that it interacts with [9:35] vitamin E. Vitamin E is another [9:36] antioxidant in our skin that helps to [9:38] protect the lipids in our skin. And when [9:40] vitamin E neutralizes free radicals in [9:42] the skin, vitamin C can actually help to [9:45] replenish it. So, there's biological [9:46] rationale behind combining vitamin C and [9:49] vitamin E topically. And some studies [9:51] actually suggest that the combination of [9:53] vitamin C and vitamin E might yield [9:55] better results than either antioxidant [9:57] used alone. So, that's kind of one of [9:59] the reasons why you frequently see a [10:01] vitamin C paired with vitamin E and [10:03] ferulic acid together in antioxidant [10:06] serums. They not only help your skin, [10:08] but they help each other out. But, I [10:10] wouldn't take that mechanistic evidence [10:12] to automatically assume that applying [10:14] this to the skin is going to be a game [10:16] changer for your skin's vitamin E [10:17] levels, either. Lastly, I want to draw [10:19] your attention to one of the bigger [10:21] issues that I see popping up when it [10:23] comes to whether or not a vitamin C [10:26] serum is worth it to you is, well, a lot [10:29] of things call themselves vitamin C [10:31] serums these days, but you got to know [10:34] what you're dealing with. Um, as you may [10:36] be aware, vitamin C formulation is not [10:40] always the easiest thing to do. It's [10:43] tricky because vitamin C is not a very [10:45] stable ingredient, and it is known for [10:48] not being so easy to get into the skin. [10:51] So, not only does it degrade, but if you [10:53] are able to keep it stable, then you [10:55] have to see, well, can I physically get [10:57] it to cross the barrier to do where to [11:00] go where it needs to go. It can degrade [11:01] with exposure to oxygen, light, all of [11:04] these things. And even if you see a [11:06] vitamin C serum that claims to have a [11:08] very high amount, that doesn't actually [11:10] mean that any meaningful amounts of [11:12] vitamin C are making their way into your [11:14] skin. So, here's where the problem [11:16] arises and why you need to be a smart [11:17] consumer if you decide that, yeah, I [11:19] think this is worth it, is because there [11:21] are numerous vitamin C derivatives out [11:24] there. You'll often hear me joke that [11:25] these are called the lottie dottie [11:27] derivatives. Cuz on the front of the [11:29] label, they'll I'll be like, vitamin C [11:31] serum. And if that is all you look at, [11:33] well, that's probably what you're going [11:34] to buy. But, here's why reading the [11:37] ingredients really matters because these [11:39] are not vitamin C proper, aka ascorbic [11:43] acid. These are ingredients known as [11:45] derivatives such as magnesium ascorbyl [11:47] phosphate, sodium ascorbyl phosphate, [11:50] ascorbyl glucoside, or tetrahexyldecyl [11:53] ascorbate. These are interesting [11:54] ingredients because yes, they are a lot [11:57] more stable. In fact, they're often [11:58] marketed that way. A highly stable form [12:01] of vitamin C. Kind of makes you think [12:03] that, oh wow, this is a really good [12:05] formula. Truthfully, we don't have good [12:07] head-to-head research on those vitamin C [12:10] derivatives. And here's the thing, we [12:12] don't have good evidence that they [12:13] actually get into your skin, nor do we [12:15] have evidence that they undergo the [12:17] conversion step necessary to turn into [12:20] ascorbic acid, or that they can even [12:23] meaningfully improve collagen production [12:25] in your skin. Now, I suspect, based on [12:27] some of the limited studies on these we [12:30] do have with all of their limitations, [12:32] that these derivatives may help with [12:35] perhaps reducing unwanted oxidative [12:38] stress at the surface of the skin. But, [12:40] if you're pursuing a vitamin C serum for [12:43] those anti-aging benefits of improving [12:45] collagen and slowing down collagen [12:47] degradation with sun exposure, you're [12:49] going to want to go with an ascorbic [12:51] acid serum, in which case you cannot [12:52] rely solely on the marketing of vitamin [12:55] C serums. You need to ask yourself, what [12:58] is the form of vitamin C? Does it [13:00] actually have ascorbic acid? That tells [13:02] you something, but unfortunately, it [13:04] still doesn't tell you the whole story [13:06] because that ascorbic acid needs to be [13:08] formulated in such a way so as to remain [13:10] stable and to meaningfully get into your [13:13] skin. Big hurdles, in other words. [13:15] Unfortunately, vitamin C serums, they [13:17] are cosmetics. So, you're never going to [13:20] know objectively if the product is [13:23] formulated in a way that leads to [13:25] meaningful improvements in collagen [13:27] levels in your skin. That being said, [13:29] many people enjoy vitamin C serums and [13:32] find, "Yeah, I have seen a visible [13:35] improvement in my skin. I'm going to [13:36] keep using." In which case, I say, [13:38] "Great." But, does that mean vitamin C [13:40] serum is a must-have and you need to be [13:43] using it? Absolutely not. Let's end on [13:45] the downsides of using vitamin C. [13:47] Probably one of the most common [13:49] downsides, it's what I encounter and [13:51] why, aside from testing them out for [13:53] review purposes, you will not find me [13:56] including it in my skin care routine, [13:57] and that is it can be a pretty [13:59] irritating. Irritation is not always a [14:02] thing that lasts for a long time, but it [14:05] can include burning, redness, dryness. I [14:07] will point out, however, that for folks [14:10] with deeper skin tones who are [14:12] especially motivated to target dark [14:14] spots, this is something you have to be [14:16] vigilant of because unwanted irritation [14:19] in the skin will directly contribute to [14:22] more stubborn, more persistent, and [14:24] worsening hyperpigmentation. Check out [14:27] my recent video on why your dark spots [14:29] are not fading. Irritation from skin [14:31] care products is one such reason that [14:34] you really need to be, again, vigilant [14:36] about and why I suggest, "Hey, if it's [14:38] not broken in your skin care routine, do [14:40] you really need to go attempting to fix [14:42] it, especially if you are vulnerable to [14:44] stubborn hyperpigmentation?" It can [14:46] backfire on you, for sure. Also, if you [14:49] have an underlying skin condition where [14:51] you have heightened sensitivity, namely [14:53] rosacea, you might not tolerate it [14:55] either. It's not to say, "Oh, if you [14:56] have rosacea, you can never use an [14:58] ascorbic acid serum." No, but you have [15:00] rosacea and you use one, you might [15:03] encounter irritation that worsens your [15:04] symptoms. In which case, yeah, it's not [15:07] a must-have. Please do not persevere [15:09] through that aggravating your rosacea. [15:11] The other limitation is that many of [15:13] them are expensive. Even the affordable [15:15] ones, it adds up. Some of the serums, [15:17] for example, that were used in some of [15:19] these clinical studies, uh one in [15:21] particular is the CE Ferulic Vitamin C [15:24] serum from SkinCeuticals. But there's [15:26] another one, the Cellex Vitamin C serum [15:29] that was used in one small clinical [15:31] study published in JAMA Otolaryngology. [15:34] These are ranging a hundred to a hundred [15:36] and twenty dollars per bottle. I think [15:39] even more for the CE Ferulic. It's been [15:41] a while since I've checked on that. [15:43] You're probably paying for maybe better [15:45] formulation, maybe better stability, and [15:48] you know at least that there's some [15:49] clinical data behind this formula. So, [15:51] you know, it it definitely could be [15:53] worth it for some folks, but that's just [15:55] cost prohibitive for others. And keep in [15:57] mind, we don't have good studies saying [15:59] to what extent is this truly superior to [16:02] some of these other more cost-effective [16:04] topicals. So, do you actually need a [16:06] Vitamin C serum? It's not a must-have [16:08] for everyone. Some groups are likely [16:10] going to benefit from the use of a [16:12] Vitamin C serum more so than others. But [16:14] if you were going to come to me and say, [16:16] "What's the most evidence-based topical [16:18] for anti-aging, for hyper- pigmentation, [16:20] for overall skin tone, for preventing [16:23] unwanted sun damage?" Arguably, it's [16:25] going to be sunscreen. And next in line [16:28] to that is going to be a topical [16:30] retinoid. Both of these together are a [16:33] real powerful combination for addressing [16:36] all of these issues that we've talked [16:37] about in today's video. All right, guys. [16:40] So, that about wraps up where I stand [16:42] with regards to this is Vitamin C a [16:44] must-have question. Like, do you have to [16:47] use it? You don't have to use it. I [16:49] don't routinely use Vitamin C in my skin [16:51] care routine, and I'm not losing a lot [16:53] of sleep over it. For other people, you [16:55] know, maybe you don't tolerate topical [16:57] retinoids or even the cosmetic versions, [17:00] which tend to be less irritating. Maybe [17:02] you're one of those people out there who [17:04] doesn't get along with niacinamide, but [17:06] you find you get along well with [17:07] ascorbic acid. Go with ascorbic acid [17:09] then. It makes sense. You will see me [17:11] use a lot of niacinamide in my skin care [17:13] routine, and I feel as though it does [17:15] something. I see benefit visually on my [17:18] skin using it at any rate. And it tends [17:20] to just happen to appear in my routine [17:22] whether I'm actively pursuing it or not [17:24] cuz it is very widespread in the skin [17:27] care industry as many of you know. But [17:28] if you don't tolerate it and you're like [17:30] going out of your way to avoid it cuz it [17:31] irritates your skin but you want a good [17:33] antioxidant with some evidence behind [17:35] it. Then it makes sense to entertain [17:37] ascorbic acid for sure. Let me know in [17:39] the comments is vitamin C a must have [17:41] for you or is it one that you have [17:43] decided to walk on [17:45] Let me know in the comments if there are [17:47] any other skin care ingredients that [17:49] you've been told are must haves and now [17:51] you're second guessing and you want a [17:53] video on. I hope you all enjoyed today's [17:55] video. If so, give it a thumbs up, share [17:57] it with your friends and as always don't [17:58] forget sunscreen and subscribe. I'll [18:00] talk to you guys tomorrow. Bye. [18:19] >> [music]