Hair, Skin and Nails Vitamins: What Is in Them and What Trials Found

A hair, skin and nails vitamin is a multi-nutrient formula built around the nutrients that hold an authorised hair, skin or nail wording in Great Britain: biotin (normal hair and normal skin), zinc (normal hair, normal nails and normal skin), selenium (normal hair and normal nails), copper (normal hair pigmentation and normal skin pigmentation), vitamin C (normal collagen formation for the normal function of skin) and, for skin alone, vitamin A, riboflavin, niacin and iodine.¹ Each wording describes what the nutrient does in everyone, and a product may carry it only where a daily portion supplies at least 15% of the nutrient reference value.^{1, 2} Collagen, silica, hyaluronic acid, keratin and MSM are common additions that carry no authorised claim.¹ The formulas that have been tested in randomised trials are branded blends, most of them run or funded by their makers, and their results belong to the whole formula, not to any one ingredient; no published trial has tested a hair, skin and nails formula in people with a measured deficiency against the same nutrients at reference amounts.^{11, 12} What a label tells you is the amount of each nutrient per daily portion against the NHS figures: biotin on a hair formula is commonly 5,000 to 10,000 micrograms against the NHS line that 0.9 mg or less a day in supplements is unlikely to cause harm, and high-dose biotin interferes with blood tests; zinc should stay within 25 mg a day from supplements unless a doctor advises more; selenium within 350 micrograms (the European upper level is 255); and a product with preformed vitamin A is not for pregnancy.^{3, 4, 7, 8, 10, 19} This page sits beneath the vitamins and minerals guide.

Evidence at a glance

• Register wordings and their 15% condition: the Great Britain nutrition and health claims register, last updated 19 May 2026.^{1, 2}
• NHS amounts and lines for biotin, zinc, selenium, copper, vitamin A and vitamin C: pages reviewed 3 August 2020, review overdue; the MHRA Safety Roundup of May 2025 on biotin and thyroid tests.^{3, 4, 5, 6, 8}
• Formula trials: a 2023 systematic review of 30 studies (17 randomised) of nutritional supplements in people with hair loss and no known deficiency, and a 2026 meta-analysis of 14 studies in 967 people of commercial oral supplements; both report positive, formula-specific results from trials mostly run by the makers.^{11, 12}
• Two EFSA opinions of 2012 that a B-vitamin and pumpkin seed oil combination and a keratin and mineral combination had not established an effect on normal hair.^{17, 18}
• Upper levels: EFSA 2023 selenium 255 micrograms a day, alopecia the critical endpoint; EFSA 2024 preformed vitamin A 3,000 micrograms RE a day on birth defects.^{19, 20}

Sources checked on 1 November 2026.

What is in a hair, skin and nails vitamin?

Read any label in the category and the same names recur, because the register fixes which nutrients may say anything about hair, skin or nails at all. The table gives each nutrient's authorised wording, the reference value that the 15% condition works from, and the NHS daily figure and supplement line.^{1, 2, 3, 4, 5, 6, 7} Riboflavin, niacin and iodine each contribute to the maintenance of normal skin and appear in some formulas for that reason; they have no hair or nail wording.¹

The second half of most labels is the additions: ingredients sold for hair, skin and nails that hold no authorised wording in Great Britain. Each has its own page here, so the table gives the register position and the trial record in a phrase.¹

Do hair, skin and nails vitamins work? What the trials measured

The trials that exist are of whole products, and that shapes what they can tell you. A 2023 systematic review in JAMA Dermatology searched for every dietary or nutritional intervention tested in people with hair loss and no known deficiency and found 30 articles: 17 randomised trials, 11 other clinical studies and two case series. The highest-quality studies showed a potential benefit for several branded multi-ingredient blends, for capsaicin with isoflavone, for omega-3 and omega-6 fats with antioxidants, for zinc, tocotrienols and pumpkin seed oil; no diet-based study met the inclusion criteria, and the authors asked for larger trials with active comparators.¹¹ A 2026 meta-analysis pooled 14 studies of commercial oral supplements in 967 adults with hair loss or thinning, most of them randomised and lasting 12 weeks to 12 months: against placebo, telogen (resting) hair density was lower by 5.91 hairs and anagen (growing) hair density higher by 10.48, while total hair count did not differ significantly; the authors call the results promising and preliminary and ask for independent research.¹²

The individual trials behind those numbers look alike. One gave 60 women with self-perceived thinning a marine protein blend or placebo twice a day for 90 days and counted more terminal hairs in a 4 cm² target area and less shedding on the blend; the trial was registered by the product's company.¹³ Another randomised 70 perimenopausal, menopausal and postmenopausal women with thinning to a botanical blend (40) or placebo (30) for six months and found terminal and total hair counts up at days 90 and 180 and shedding down by 32%; the series is funded by the maker.¹⁴ The only placebo-controlled trial of a hair gummy in the literature searched for this page gave 65 women aged 18 to 60 with thinning hair two gummies a day of a B-vitamin, zinc and botanical formula, or placebo, for six months: hair density rose 10.1% against a 2% fall on placebo, while tensile strength improved in both groups with no significant difference between them; the first author is an employee of the gummy's maker.²⁵ A 2026 open-label study of a millet, pantothenic acid, cystine and biotin capsule in 112 adults with light diffuse hair loss (94% women) measured higher hair density and a 59% fall in hair loss against baseline after 12 weeks, with no placebo group and the maker involved in design, writing and the decision to publish.¹⁵ A 2025 network meta-analysis of 19 randomised trials in 1,658 people with pattern hair loss ranked a range of supplements on hair density; the ones that beat placebo were again specific blends and extracts.¹⁶

So the trials show what a specific blend did in a specific group, measured by phototrichogram over three to twelve months, usually in women with self-perceived thinning, usually paid for by the company that sells it. None isolates the vitamins. That is also why the formula-level wording stays off the label: in 2012 the European Food Safety Authority assessed a combination of B vitamins, including biotin, with pumpkin seed oil, and a combination of keratin with copper, zinc, niacin, pantothenic acid, pyridoxine and biotin, and concluded in both cases that a cause and effect relationship with the maintenance of normal hair had not been established, the only study offered for the second being uncontrolled.^{17, 18} A label may therefore say that zinc contributes to the maintenance of normal hair; it may not say that the formula reduces hair loss.¹

Hair vitamins or a multivitamin?

The register makes no distinction. The same wording, "zinc contributes to the maintenance of normal hair", is available to any food that is a source of zinc, whether the pot says hair, skin and nails or multivitamin.^{1, 2} What differs is the amount of each nutrient per daily portion and which non-nutrient additions are present. A women's multivitamin typically lists biotin near the 50 microgram reference value alongside iron; a hair formula typically lists biotin far above it, with collagen, silica or hyaluronic acid added. How to choose a multivitamin for women and is it good to take a multivitamin every day cover the multivitamin side; how to read a supplement label covers the arithmetic.

Biotin: the one line that matters on the label

Biotin contributes to the maintenance of normal hair and normal skin, and the people whose hair has measurably improved on it are those who were short of it: a systematic review found 18 published cases, every one in a person with an underlying cause of deficiency.^{1, 21} The NHS sets no daily amount, says biotin is found in a wide range of foods at very low levels, and says that "taking 0.9mg or less a day of biotin in supplements is unlikely to cause any harm", with not enough evidence on higher daily doses; the labelling reference value is 50 micrograms.^{2, 3} Hair formulas commonly carry 5,000 to 10,000 micrograms, and 10 mg a day is the dose a 2017 JAMA study described as common in over-the-counter supplements.¹⁰

The rule attached to those amounts is about blood tests, not toxicity. In six healthy adults, 10 mg of biotin a day for seven days interfered with 9 of 23 laboratory immunoassays that use biotin in their chemistry, including thyroid tests, and none of 14 that do not; competitive assays read falsely high and sandwich assays falsely low.¹⁰ The MHRA's May 2025 Safety Roundup says biotin "may interfere with thyroid immunoassays and the risk of interference increases with higher doses of biotin", and asks clinicians to ask anyone with suspected thyroid dysfunction about their biotin intake; the NHS levothyroxine page lists "biotin (vitamin B7) as it can affect your thyroid tests" among the things that may not mix well.^{8, 9} If you take a hair formula and have a blood test booked, tell the clinic and ask how long to stop it beforehand. Is biotin good for hair growth covers the evidence and the food amounts.

Zinc, selenium and copper: the amounts to add up

Zinc contributes to the maintenance of normal hair, nails and skin, and the NHS line is firm: "Do not take more than 25mg of zinc supplements a day unless advised to by a doctor", because "taking high doses of zinc reduces the amount of copper the body can absorb", which can lead to anaemia and weakening of the bones.^{1, 4} Selenium contributes to the maintenance of normal hair and nails; the NHS says 350 micrograms or less a day in supplements is unlikely to cause harm and that too much causes selenosis, which "in its mildest form, can lead to loss of hair and nails".^{1, 4} The European Food Safety Authority set its 2023 upper level lower, at 255 micrograms a day from all sources, with alopecia as the critical endpoint and regular users of high-dose supplements and regular Brazil nut eaters as the groups likely to exceed it.¹⁹ In September 2026 the UK Committee on Toxicity, reviewing selenium in the maternal diet, endorsed in draft minutes the 255 microgram figure as its guidance value in place of the older 450 microgram expert-group value, noting that NHS advice still rests on that 2003 assessment and that a single high-strength supplement can exceed 255; its final statement had not been published at 1 November 2026.²⁶ Copper contributes to normal hair and skin pigmentation, and the NHS puts the harm line at 10 mg a day from food, water and supplements together.^{1, 4}

The arithmetic matters because these three turn up in more than one pot. A hair formula and a multivitamin, or a hair formula and a zinc and vitamin C capsule, can together pass 25 mg of zinc or 350 micrograms of selenium when neither does alone. Add the daily portions across everything you take. Does zinc help with hair loss covers the zinc trials, zinc and copper the balance between the two, and thyroid supplements: iodine and selenium the selenium evidence.

Vitamin A, and who should not take a hair vitamin

Vitamin A contributes to the maintenance of normal skin, which is why some formulas include it, and it is the ingredient that decides who should not take the product.¹ The NHS pregnancy page says: "Do not take cod liver oil or supplements containing vitamin A (sometimes called retinol) when you're pregnant. Too much vitamin A can harm your baby's development."⁷ For everyone else the NHS asks that food and supplements together stay at or under 1.5 mg a day, and says "if you eat liver every week, do not take supplements that contain vitamin A".⁵ The European upper level for preformed vitamin A is 3,000 micrograms RE a day, set in 2024 on birth defects, with the advice that women planning or in a pregnancy should not eat liver products.²⁰

On an ingredient list, preformed vitamin A appears as retinol, retinyl acetate or retinyl palmitate; beta-carotene is the plant precursor and is not covered by the pregnancy warning, though smokers are advised against beta-carotene supplements.²⁰ What is vitamin A good for and pregnancy vitamins: what the NHS recommends go further.

Collagen, silica, hyaluronic acid, keratin and MSM in a hair formula

Collagen. Measured for nails in one open-label study of 25 people and for hair as one outcome among several in placebo-controlled trials; a formula may list collagen but may not claim for it.¹ Collagen for hair and nails holds the figures, and what vitamins to take with collagen covers vitamin C's authorised link to collagen formation.

Silica. Horsetail and bamboo extracts are sold as plant sources of silicon, and the register treats every silicon wording the same way, as non-authorised; the two placebo-controlled trials of one silicon form, in 50 and 48 women, measured skin roughness and hair break load.¹ What is silica good for sets out the forms and the trials.

Hyaluronic acid. A swallowed polysaccharide with placebo-controlled skin trials at about 120 mg a day, most run by the makers; is it safe to take a hyaluronic acid supplement covers doses and safety.

Keratin. Hair and nails are made of keratin, which is why it is sold for them, but swallowed keratin is digested to amino acids like any other protein. Keratin has no entry of its own in the register, the cystine and cysteine hair wordings are non-authorised, and the 2012 EFSA opinion on a keratin and mineral combination found no established effect on normal hair.^{1, 18} The trials that exist tested keratin alongside added vitamins and minerals, so the keratin cannot be separated from them.

MSM. Methylsulfonylmethane is a sulphur compound with two small skin studies, both from the ingredient's supplier, and no human trial for hair or nails. What is MSM covers the joint trials.

Women, men and life stages

Heavy periods and iron. The NHS lists iron deficiency among the causes of temporary hair loss, and hair loss and spoon-shaped nails among the less common symptoms of iron deficiency anaemia.^{22, 23} Iron is not what a hair formula is built around, and the question is settled by a ferritin test, not a label: iron and heavy periods gives the thresholds and what is ferritin explains the test.

Pregnancy and breastfeeding. No preformed vitamin A, and tell the midwife about biotin before antenatal blood tests, because high doses can distort thyroid and other results.^{7, 8, 10} Ask a midwife or pharmacist before continuing any hair formula.

The menopause. The NHS lists "hair thinning or hair loss" and "skin changes, including dry and itchy skin" among menopause symptoms (page reviewed 19 May 2026).²⁴ The one placebo-controlled formula trial in this group is the 70-woman botanical blend above, funded by its maker.¹⁴ The first signs of perimenopause carries the NHS list and collagen and the menopause the collagen trials in menopausal women.

Men. Male pattern baldness is permanent and usually runs in the family, in the NHS's words, and no nutrient wording covers it.²² Supplements for men, saw palmetto and pumpkin seed oil set out the trials in men.

Fast weight loss. Weight loss is on the NHS list of causes of temporary hair loss; hair loss on Mounjaro covers the shedding that follows a large, fast drop in weight.²²

How to read the label

Every figure on the panel is for the daily portion, so a two-gummy portion taken as one halves it and taken as four doubles it. Micrograms appear as mcg or µg; 1 mg is 1,000 micrograms, so 10,000 mcg of biotin is 10 mg.² A nutrient may carry its authorised wording only where the portion supplies at least 15% of the reference value in the table above; "contributes to" is the permitted verb, and "boosts", "grows" or "strengthens" is not register wording.^{1, 2} Advisory statements worth reading are the vitamin A pregnancy line, the zinc line and any note about blood tests.^{3, 4, 7} On a gummy, read the sugars line too. Do vitamin gummies actually work and sugar and sweeteners in gummy vitamins cover the format.

Who should check first

Anyone who is pregnant or breastfeeding, anyone on levothyroxine or with a thyroid condition, anyone with kidney disease or haemochromatosis, and anyone with sudden, patchy or persistent hair or nail changes should ask their GP or pharmacist first.^{7, 8, 9} Anyone with a blood test booked tells the clinic about biotin.⁸ A suspected reaction to a food supplement is reported to your local authority's food safety team, which works with the Food Standards Agency; the Yellow Card scheme is for medicines.

What we don't know

• Whether a hair, skin and nails formula does more than the same nutrients at reference amounts. No trial has compared them.^{11, 12}
• How common low biotin is in the UK. No national survey measures it.³
• Whether any formula helps people with a measured deficiency and hair loss. The formula trials excluded known deficiency; the deficiency evidence is case reports.^{11, 21}
• Literature searched to 1 November 2026.

Frequently asked questions

Do hair, skin and nails vitamins really work?

The trials of whole branded formulas, mostly funded by their makers, measured more growing hairs and less shedding than placebo over three to twelve months in women with self-perceived thinning; a 2026 pooling of 14 such studies found no significant difference in total hair count.^{11, 12} The nutrients inside contribute to the maintenance of normal hair, skin or nails at label amounts, and where hair is thinning because of a deficiency, correcting the deficiency is what the case evidence shows working.^{1, 21}

How many hair, skin and nails gummies should I take?

The daily portion on the label, and never more, because biotin and zinc are where the amounts climb: the NHS lines are 0.9 mg of biotin and 25 mg of zinc from supplements a day.^{3, 4} Count any other pot that contains zinc or selenium in the same total.

Can I take a hair vitamin when pregnant or breastfeeding?

Not one that contains preformed vitamin A (retinol, retinyl acetate or retinyl palmitate): the NHS says not to take supplements containing vitamin A in pregnancy.⁷ Tell the midwife about biotin before blood tests, and ask before continuing any formula.⁸ Pregnancy vitamins covers what the NHS does recommend.

Hair vitamins or a multivitamin, which is better?

Both may carry the same register wording for the same nutrient; neither may claim more.¹ Read the amounts per daily portion against the table above and decide what you want in the pot, including whether you want collagen, silica or hyaluronic acid alongside the nutrients.

Sources

1. Department of Health and Social Care. Great Britain nutrition and health claims (NHC) register. Published 31 December 2020, last updated 19 May 2026. gov.uk. Register of authorised and non-authorised wordings; the legal basis is Regulation (EU) No 432/2012 as retained in UK law.
2. Regulation (EU) No 1169/2011 as retained in UK law, Annex XIII, nutrient reference values and the 15% "significant amount" condition. legislation.gov.uk.
3. NHS. Vitamins and minerals: B vitamins and folic acid. Page reviewed 3 August 2020. nhs.uk.
4. NHS. Vitamins and minerals: others (copper, selenium, zinc). Page reviewed 3 August 2020. nhs.uk.
5. NHS. Vitamins and minerals: vitamin A. Page reviewed 3 August 2020. nhs.uk.
6. NHS. Vitamins and minerals: vitamin C. Page reviewed 3 August 2020. nhs.uk.
7. NHS. Pregnancy vitamins and supplements. Page reviewed 3 June 2026. nhs.uk.
8. MHRA. Safety Roundup, May 2025: be aware of the potential for biotin interference on thyroid function laboratory tests. gov.uk.
9. NHS. Levothyroxine: taking it with other medicines and supplements. Page reviewed 6 July 2026. nhs.uk.
10. Li D, et al. Association of biotin ingestion with performance of hormone and nonhormone assays in healthy adults. JAMA, 2017. PubMed 28973622. Non-randomised crossover study, 6 healthy adults, 10 mg a day for 7 days; US National Institutes of Health funding; an erratum is on record and the figures here are from the corrected abstract.
11. Drake L, et al. Evaluation of the safety and effectiveness of nutritional supplements for treating hair loss: a systematic review. JAMA Dermatology, 2023. PubMed 36449274. Systematic review, 30 articles (17 randomised trials, 11 other clinical studies, 2 case series), searched to October 2021; funding not stated on PubMed.
12. Alanazi R, et al. Evaluating the effectiveness of commercial oral supplements for hair growth: a systematic review and meta-analysis. Journal of Cosmetic Dermatology, 2026. PubMed 41954038. Systematic review and meta-analysis, 14 studies, 967 participants, 12 weeks to 12 months; authors declare no conflicts of interest.
13. Ablon G. A 3-month, randomized, double-blind, placebo-controlled study evaluating the ability of an extra-strength marine protein supplement to promote hair growth and decrease shedding in women with self-perceived thinning hair. Dermatology Research and Practice, 2015. PubMed 25883641. Randomised double-blind placebo-controlled trial, 60 women, 90 days; trial registered by the product's company.
14. Ablon G, Kogan S. A randomized, double-blind, placebo-controlled study of a nutraceutical supplement for promoting hair growth in perimenopausal, menopausal, and postmenopausal women with thinning hair. Journal of Drugs in Dermatology, 2021. PubMed 33400421. Randomised double-blind placebo-controlled trial, 70 women (40 active, 30 placebo), 6 months; funded by the product's maker.
15. Proksch E, et al. Effectiveness, tolerability, and acceptance of a food supplement in the management of non-illness-related hair loss. Journal of Cosmetic Dermatology, 2026. PubMed 42144810. Open-label multicentre study, 112 adults (109 analysed), 12 weeks, no placebo group; funded by the product's maker, which was involved in design, writing and the decision to publish; one author an employee.
16. Zhou L, Zhu W, Chen Y, et al. Effects of dietary supplements on androgenetic alopecia: a systematic review and network meta-analysis. Frontiers in Nutrition, 2025. PubMed 41561175. Network meta-analysis, 19 randomised trials, 1,658 patients; authors declare no commercial conflicts.
17. EFSA Panel on Dietetic Products, Nutrition and Allergies. Scientific opinion on a health claim related to a combination of thiamin, riboflavin, niacin, pantothenic acid, pyridoxine, D-biotin and pumpkin seed oil and maintenance of normal hair. EFSA Journal, 2012. PubMed 42016079. Scientific opinion; cause and effect not established.
18. EFSA Panel on Dietetic Products, Nutrition and Allergies. Scientific opinion on a health claim related to a combination of keratin, copper, zinc, niacin, pantothenic acid, pyridoxine and D-biotin and maintenance of normal hair. EFSA Journal, 2012. PubMed 42016093. Scientific opinion; one uncontrolled single-arm study submitted; cause and effect not established.
19. EFSA Panel on Nutrition, Novel Foods and Food Allergens (Turck D, et al.). Scientific opinion on the tolerable upper intake level for selenium. EFSA Journal, 2023. PubMed 36698500. Scientific opinion; upper level 255 micrograms a day, from a lowest-observed-adverse-effect level of 330 micrograms in a large randomised trial with an uncertainty factor of 1.3.
20. EFSA Panel on Nutrition, Novel Foods and Food Allergens (Turck D, et al.). Scientific opinion on the tolerable upper intake level for preformed vitamin A and beta-carotene. EFSA Journal, 2024. PubMed 38846679. Scientific opinion; upper level 3,000 micrograms RE a day retained on teratogenicity.
21. Patel DP, Swink SM, Castelo-Soccio L. A review of the use of biotin for hair loss. Skin Appendage Disorders, 2017. PubMed 28879195. Systematic review of case reports and trials, 18 cases, all with an underlying pathology; funding not stated on PubMed.
22. NHS. Hair loss. Page reviewed 24 January 2024. nhs.uk.
23. NHS. Iron deficiency anaemia. Page reviewed 26 January 2024. nhs.uk.
24. NHS. Menopause: symptoms. Page reviewed 19 May 2026. nhs.uk.
25. Martin-Biggers J, Barbosa Bueno de Campos M. A randomized, placebo-controlled clinical study evaluating a dietary supplement for hair growth. Journal of Clinical and Aesthetic Dermatology, 2024. PubMed 39758217. Randomised placebo-controlled trial, 65 women aged 18 to 60 with thinning hair, 6 months; first author an employee of the gummy's maker, second author at a contract testing company.
26. Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment. Draft minutes of the 8th September 2026 COT meeting, item 6: selenium in the maternal diet (paper TOX/2026/31). Draft minutes, updated 15 October 2026; a final statement is to follow. gov.uk.

Spotted something out of date? Email support@wellgard.co.uk with the page address and the sentence.

This article is general information, not medical advice. Hair or nail changes that are sudden, patchy or persistent need a GP; tell whoever takes your blood if you take high-dose biotin.