Vitamin C for Hair: What the Research Shows

Vitamin C is essential for the skin, but we found no trial showing that vitamin C supplements or topical vitamin C grow hair. A review of vitamins and minerals in hair loss calls the evidence enormous but conflicting, and a market analysis found many vitamin C supplements exceed recommended doses.

Here's what the research says.

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Key Takeaways

• We found no trial showing vitamin C grows hair or reduces hair loss.
• A review of vitamins and minerals in non-scarring alopecia, including vitamin C, called the evidence conflicting and said large double-blind placebo-controlled trials are needed.
• A review of vitamin C in skin health says normal skin contains high concentrations of vitamin C, which supports collagen synthesis and antioxidant protection, but the efficacy of topical vitamin C compared with dietary intake is poorly understood.
• An analysis of 106 vitamin C supplements found more than three quarters exceeded the recommended daily dose and nearly 40% exceeded a potential upper safety level.

What Is Vitamin C?

Vitamin C (ascorbic acid) is a water-soluble vitamin found in fruit and vegetables and in supplements.

Does Vitamin C Help Hair?

Not shown. The skin research doesn't extend to scalp hair, and the micronutrient review calls for trials that haven't been done.

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Using Vitamin C Sensibly

• Get it from food first. Dietary intake is the focus of the skin review.
• Check supplement doses. Many products contain far more than the recommended amount.
• Tell your doctor about all supplements, and ask about hair loss causes.

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What The Research Shows

Vitamins And Minerals In Hair Loss

A review summarized the role of vitamins A, B, C, D and E, iron, selenium and zinc in non-scarring alopecia. It stated that micronutrients play an important but not entirely clear role in follicle development and immune function, that the evidence is enormous and conflicting, and that deficiency may represent a modifiable risk factor. The authors said large double-blind placebo-controlled trials are required to determine the effect of specific micronutrient supplementation on hair growth (Almohanna et al., 2019).

Vitamin C And The Skin

A review of vitamin C in skin health explains that normal skin contains high concentrations of vitamin C, which stimulates collagen synthesis and helps protect against UV-induced photodamage. It notes that the efficacy of adding vitamin C to topical products, as opposed to optimizing dietary intake, is poorly understood, and identifies areas where lack of evidence limits understanding (Pullar et al., 2017). It is about skin, not hair.

What Is In Supplements

A market analysis of 106 vitamin C preparations sold online in Germany and the USA found a mean daily dose of 613.9 mg, against a recommended 90 to 110 mg for adults, and full bioavailability reached from doses of 100 to 400 mg. More than three quarters of products exceeded the recommended daily dose and nearly 40% exceeded a potential upper safety level. Some were missing required or recommended warnings, and more than a third contained other active ingredients that might raise overdose risk (Decke and Seifert, 2025). The analysis wasn't about hair.

Vitamin A is the other vitamin often discussed; see vitamin A and hair.

See also: Vitamin B12 for Hair: What the Research Shows · Vitamin E Oil for Hair: What the Research Shows

To see how this fits with the other nutrients hair needs, read our guide to the best vitamins for hair growth.

Vitamin C is one of the ingredients in FullyVital's Hair Revival Supplements and Hair Skin Gut Collagen. For how the evidence for each ingredient in the line stacks up, see our evidence-tier breakdown.

Frequently Asked Questions

Does vitamin C help hair growth?

We found no trial showing that.

Can low vitamin C cause hair loss?

Reviews list vitamin C among micronutrients studied in hair loss, but they call the evidence conflicting.

How much vitamin C should I take?

The recommended daily dose for adults in that analysis was 90 to 110 mg. Ask your doctor about supplements.

References

1. Almohanna HM, Ahmed AA, Tsatalis JP, et al. The Role of Vitamins and Minerals in Hair Loss: A Review. Dermatol Ther (Heidelb). 2019. PubMed
2. Pullar JM, Carr AC, Vissers MCM. The Roles of Vitamin C in Skin Health. Nutrients. 2017. PubMed
3. Decke J, Seifert R. Market analysis of vitamin C-containing dietary supplements in Germany and the USA: Consumer information and risks and benefits. Naunyn Schmiedebergs Arch Pharmacol. 2025. PubMed