Do Hair Supplements Like Nutrafol and Viviscal Work?What Trials Show
HairArticleBranded hair supplements point to clinical trials, and those trials did report more hairs and less shedding. But they were small, from 40 to 70 women, and a 2026 review of 14 studies found no clear difference in total hair count, calling for more independent research. Here is what the trials measured, what they didn't, and what to check before you spend.
In this article
Hair supplements are a big business, and their marketing often leans on “clinically tested” claims. Here is what the published trials of two of the best-known brands found, and what a recent review made of them all.
The trials
| Supplement and trial | Women | What it found |
|---|---|---|
| Nutrafol Women’s, 6 months | 26 on the supplement, 14 on placebo1 | More terminal and fine hairs in the measured area at 3 and 6 months1 |
| Nutrafol Women’s Balance, 6 months, around menopause | 40 on the supplement, 30 on placebo2 | More hairs, and shedding about 32% lower by 6 months2 |
| Viviscal Extra Strength, 3 months | 30 on the supplement, 30 on placebo3 | More terminal hairs and less shedding3 |
No side effects were reported in these trials.13
These results look good, but the trials were small, short, and measured hairs in a single small patch of scalp.
The review
A review pooled 14 studies with 967 people, covering Nutrafol, Viviscal and six other commercial supplements.4
- Several lab measures of hair growth favored the supplements, and people said their hair felt thicker and shed less.4
- But total hair count showed no clear difference.4
- Side effects were minimal.4
- The reviewers called the results promising but preliminary, and said more rigorous, independent research is needed.4
Before you buy
- Find the cause first. Shedding from illness, iron deficiency or thyroid problems needs its own fix. See iron and ferritin tests for hair loss.
- Check for biotin, which can skew some blood tests. See thyroid tests and biotin and do hair vitamins and biotin work?
- Compare with established treatments such as minoxidil. See oral vs topical minoxidil.
- Give any product a fair, dated trial with photos, so you can judge it fairly.
Try: “I’m thinking about a hair supplement for thinning. Should we check iron and thyroid first, and how would a supplement compare with minoxidil for me?”
Hair, Everywhere covers this in Chapter 2, “Gummies, Tweezers, and Shrugs,” in a section called “Answer One: It’s a Missing Vitamin.” Its Hair Log keeps the same monthly photos with dates, so any product gets judged against where you started. See the book.
This article is for general educational purposes only and is not medical advice. It isn't a substitute for diagnosis or treatment from a qualified healthcare professional who knows your health history. Tell your clinician about supplements, especially before blood tests, since some contain biotin that can affect results, and check with a pharmacist if you're pregnant or take other medicines. See a doctor for patchy hair loss or shedding that lasts. Girl Playbook does not endorse any specific product, test, or provider.
Girl Playbook sells this book. It provides education and worksheets, not individualized medical care.
Sources
The research behind this article, in the order it’s cited. How we source our articles.
- Journal of Drugs in Dermatology, 2018 trial (abstract via PubMed), 2018A Six-Month, Randomized, Double-Blind, Placebo-Controlled Study Evaluating the Safety and Efficacy of a Nutraceutical Supplement for Promoting Hair Growth in Women With Self-Perceived Thinning Hair (opens in a new tab)abc
- Journal of Drugs in Dermatology, 2021 trial (abstract via PubMed), 2021A Randomized, Double-Blind, Placebo-Controlled Study of a Nutraceutical Supplement for Promoting Hair Growth in Perimenopausal, Menopausal, and Postmenopausal Women With Thinning Hair (opens in a new tab)ab
- Dermatology Research and Practice journal (via PubMed Central), 2015A 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 (opens in a new tab)abc
- Journal of Cosmetic Dermatology (via PubMed Central), 2026Evaluating the Effectiveness of Commercial Oral Supplements for Hair Growth: A Systematic Review and Meta-Analysis (opens in a new tab)abcde
Spotted something out of date? Tell us and we’ll check it.
