Supplements for hair can help only when your diet lacks something your hair needs. Under EU and Swiss law, three nutrients contribute to the maintenance of normal hair: biotin, zinc and selenium; copper contributes to normal hair pigmentation. Low iron is a common, treatable cause of hair shedding, especially in women. No supplement changes hereditary hair loss, and taking more than you need can even harm your hair.
Key facts about supplements for hair
- Losing about 50 to 100 hairs a day is normal; scalp hair grows roughly 1 cm a month.
- Adults need about 40 µg of biotin a day; true biotin deficiency is rare.
- Zinc needs are 7–10 mg a day for women and 11–16 mg for men (D-A-CH, depending on phytate intake). The upper limit is 25 mg a day.
- Selenium needs are 60–70 µg a day (D-A-CH); EFSA's upper limit is 255 µg. Too much selenium can itself cause hair loss.
- Women before menopause need 16 mg of iron a day, men 11 mg (EFSA). Iron should be supplemented in larger doses only after a blood test.
Do supplements for hair actually work?
They work when they correct a deficiency, and rarely beyond that. Hair follicles are among the fastest-dividing cells in the body, so a shortage of protein, energy, iron, zinc or biotin can show up as thinning or shedding. When the gap is closed, hair usually recovers over several months.
Reviews of the research find little evidence that extra vitamins or minerals help hair in people who are already well supplied. Studies have looked at biotin, zinc, vitamin D and iron in different types of hair loss, with mixed or weak results outside of a proven deficiency. A supplement is therefore a way to cover your needs reliably, not a hair growth treatment.
Breakage and dullness are a separate issue: they mostly come from heat, bleaching, colouring, friction and sun, and they are best addressed with gentle hair care rather than with pills.
Which nutrients matter for hair?
| Nutrient | Authorised role (EU/CH) | Daily need, adults | Good food sources |
|---|---|---|---|
| Biotin | Maintenance of normal hair and skin | 40 µg | Eggs, nuts, seeds, oats, legumes |
| Zinc | Maintenance of normal hair, nails and skin | 7–16 mg | Pumpkin seeds (about 7 mg per 100 g), oats, lentils, cheese |
| Selenium | Maintenance of normal hair and nails | 60–70 µg | Brazil nuts, fish, eggs, wholegrains |
| Copper | Normal hair pigmentation | 1.0–1.5 mg | Nuts, seeds, wholegrains, cocoa |
| Iron | Normal oxygen transport; normal formation of red blood cells and haemoglobin | 11 mg (men), 16 mg (women) | Legumes, tofu, oats, seeds, meat |
| Vitamin C | Increases iron absorption; normal collagen formation | 95–110 mg | Peppers, berries, citrus, kiwi |
Your scalp is skin, so the nutrients that contribute to the maintenance of normal skin also play a part: vitamin A, riboflavin, niacin, biotin, zinc and iodine. Our guide to the best vitamins for your skin covers them in detail.
Biotin: the best-known hair vitamin
Biotin contributes to the maintenance of normal hair, and a real deficiency causes hair loss. In people who already get enough, however, extra biotin has not been shown to make hair grow faster or thicker. High-dose biotin (5–10 mg) can also distort blood tests. Read more in our article on biotin benefits, weight gain and safety.
Zinc and selenium
Both trace elements contribute to the maintenance of normal hair. Zinc deficiency can cause hair loss, while too much zinc can lower copper levels. Selenium is needed only in micrograms, and an excess leads to brittle hair and hair loss, so more is clearly not better. See our guides to the benefits of zinc and to selenium.
Iron and hair shedding
Iron has no authorised hair claim, but low iron stores (measured as ferritin) are one of the most frequently studied factors in diffuse hair shedding in women. Studies disagree on the exact threshold, so a doctor should interpret your blood values. Do not take high-dose iron without a test: excess iron is harmful. Our article on iron for women and men explains needs and sources.
What causes hair loss?
Most hair loss has nothing to do with vitamins. The common causes are:
- Hereditary hair loss (androgenetic alopecia): the most common form in both men and women; it depends on genes and hormones, not on nutrition.
- Telogen effluvium: diffuse shedding that starts two to three months after a trigger such as fever, surgery, childbirth, a crash diet, severe stress or low iron.
- Thyroid disorders, both an underactive and an overactive thyroid.
- Hormonal changes, for example after pregnancy, during menopause or with polycystic ovary syndrome.
- Alopecia areata, an autoimmune condition that causes round bald patches.
- Medicines and an excess of some nutrients, especially vitamin A and selenium.
See a doctor or dermatologist if hair loss is sudden, patchy, comes with itching or scaling, or lasts longer than about three months. A blood test (blood count, ferritin, thyroid values) is often the right first step.
Hair supplements for women and men: what differs?
Women more often have low iron stores because of menstrual blood loss, and they experience hormonal hair changes after childbirth and during menopause. Shedding after pregnancy is common and usually settles within a year; during breastfeeding, discuss any supplement with your doctor or midwife. Men are more often affected by hereditary hair loss, which starts at the temples or crown and cannot be changed by nutrition. Men also need more zinc than women.
How long until you see results?
Hair grows slowly, about 1 cm a month, and a follicle that has shed its hair rests for around three months before it starts a new one. If a deficiency was the cause, it usually takes three to six months to see less shedding and longer to see more length or volume. If nothing has changed after six months, the cause is probably not nutritional.
Hair-related nutrients in Sanbera Daily Essentials
Sanbera's daily multivitamins are designed to complement a balanced diet, not to act as a hair treatment. Per daily dose of 3 tablets (% of the NRV):
| Nutrient | Daily Essential Women | Daily Essential Men |
|---|---|---|
| Biotin | 25 µg (50%) | 25 µg (50%) |
| Zinc | 2.5 mg (25%) | 4 mg (40%) |
| Selenium | 12.5 µg (23%) | 12.5 µg (23%) |
| Iron | 7 mg (50%) | 3.5 mg (25%) |
| Vitamin C | 43.1 mg (54%) | 51.8 mg (65%) |
| Vitamin A | 200 µg (25%) | 200 µg (25%) |
In Daily Essential Women and Daily Essential Men, biotin, zinc and selenium contribute to the maintenance of normal hair. Iron contributes to normal oxygen transport and vitamin C increases iron absorption. The women's formula contains more iron, the men's more zinc; the men's formula also contains guarana, a source of caffeine. All amounts stay well below the upper limits, which matters if you also use a separate hair product: add up everything you take.
Frequently asked questions
Which supplements help with hair growth?
Only supplements that close a real gap. Biotin, zinc and selenium contribute to the maintenance of normal hair, and iron matters if your stores are low. If your diet already covers these nutrients, no supplement has been shown to make healthy hair grow faster or thicker. Hair grows about 1 cm a month whatever you take.
Which supplement is best for hair loss in women?
There is no single best product. Start with the cause: in women, low iron stores, thyroid problems, hormonal changes after pregnancy or in menopause, and hereditary hair loss are common. A blood test shows whether iron or another nutrient is low. A multivitamin with biotin, zinc and selenium can cover everyday needs, but it cannot replace a diagnosis.
How much zinc should I take for hair?
Aim to meet your daily need, 7–10 mg for women and 11–16 mg for men, from food and supplements combined. Do not exceed 25 mg a day over the long term: too much zinc lowers copper levels, and there is no evidence that high doses help hair if you are not deficient.
Can supplements help against grey hair?
Not for normal, age-related greying, which is mainly genetic. Copper contributes to normal hair pigmentation, and studies have linked premature greying with low vitamin B12, iron or copper, but correcting a deficiency rarely restores the original colour. If greying starts very early, a doctor can check for an underlying cause.
Is magnesium good for hair growth?
There is no authorised claim and no good evidence that magnesium supports hair growth. Magnesium contributes to normal protein synthesis and cell division in general, and most people get enough from wholegrains, nuts, seeds and leafy greens. Focus on biotin, zinc, selenium and iron status instead.
Sources
- European Commission: EU Register of nutrition and health claims
- Almohanna HM, Ahmed AA, Tsatalis JP, Tosti A. The role of vitamins and minerals in hair loss: a review. Dermatology and Therapy, 2019.
- Guo EL, Katta R. Diet and hair loss: effects of nutrient deficiency and supplement use. Dermatology Practical & Conceptual, 2017.
- Patel DP, Swink SM, Castelo-Soccio L. A review of the use of biotin for hair loss. Skin Appendage Disorders, 2017.
- EFSA Panel on Nutrition: Scientific opinion on the tolerable upper intake level for selenium. EFSA Journal, 2023.
- German Nutrition Society (DGE): D-A-CH reference values for nutrient intake
This article is for general information and does not replace advice from a doctor or pharmacist. Food supplements are not a substitute for a varied, balanced diet and a healthy lifestyle.