Do Hair Growth Supplements Actually Work? Experts Weigh In

colorful pills vitamins scattered across pink table top

Tatjana Zlatkovic / Stocksy

You've heard of hair growth supplements that claim to give you thick, voluminous, and lustrous locks, but do these products actually work? Whether your hair is thinning or you just want to make your mane a little longer, hair-growth supplements are a well-known "treatment."

Surely if there were a miracle-in-a-bottle pill, we'd all be on board and have a Rapunzel-like head of hair. Since that's clearly, and sadly, not the case, it leaves us feeling skeptical about whether or not we're just popping placebos. To answer our questions about hair-growth supplements, we turned to Dr. Rick Mizuguchi of Mount Sinai and Dr. Jennifer Herrmann of Moy Fincher Chipps.

Ahead, check out what you need to know about hair growth supplements and if they actually work.

Meet the Expert

  • Dr. Rick Mizuguchi, MD, is a board-certified dermatologist at Mount Sinai. He has an array of experience and particular expertise in cosmetic dermatology.
  • Dr. Jennifer Herrmann, MD, is a board-certified dermatologist and dermatological surgeon at Moy Fincher Chipps. Her specialties include laser treatments, reconstructive surgery, and cosmetic fillers.

What Are Hair Growth Supplements?

Hair health is impacted by numerous factors, including genetics, stress, hormones, medical conditions, and nutrition.

The types of hair supplements correlate with the different concerns you can come across. Herrmann says supplements "can be grouped into those that replenish true deficiencies or insufficiencies, others that decrease inflammation, those that reduce oxidative stress, others that improve gut health (which in turn keeps fewer potentially inflammatory molecules from entering the body and effecting hair), those that reduce hormonal influences that impact hair loss, and those that decrease inflammation."

Common ingredients in hair growth supplements include vitamins (particularly vitamins A, C, and multiple B vitamins), minerals such as zinc and selenium, herbal ingredients such as saw palmetto, and food content like collagen powders and fish oils. 

"Some supplements aim to improve one’s ability to tolerate stress (ashwagandha), others decrease inflammation (curcumin), some act as potent antioxidants (vitamin E), others aim to reduce negative hormonal influences (saw palmetto), and some truly 'supplement' when there are vitamin or mineral deficiencies," says Herrmann.

Do Hair Supplements Really Work?

We hate to bust this myth, but doctors say that hair supplements don't typically work for most people. "I don't really believe in any of the hair supplements that are out there," says Mizuguchi. "I do think that there is growing evidence that iron supplementation in some women with proven low ferritin [the protein that stores iron] levels should take supplementation as it is a vital cofactor for hair growth." However, Mizuguchi advises you to consult with a doctor before taking iron, since too much could lead to serious liver damage.

And while you've probably heard of biotin, a common ingredient in many hair supplement products, it's important to know that it primarily addresses hair strength. "Biotin is another supplement that's often prescribed, especially for women of color, because it's supposed to be good for hair breakage," says Mizuguchi. "A lot of people mistake it as something that is good for hair thinning, but biotin deficiency causes hair breakage and not hair loss."

"Honestly, there is very little well-researched data on supporting that biotin improves hair growth in those who are not deficient," adds Herrmann.

How to Address Thinning Hair

If thinning hair is your issue, Herrmann says it's important to figure out why hair loss is happening before choosing a treatment path. Talk with your doctor about the possible causes of your hair loss to determine which treatment suits your needs. "Are you losing hair because of changing hormones? Do you have a dermatologic condition causing discrete bald patches? Or have you over-processed to the point where your fried locks are brittle, breaking, and simply falling out? Better understanding the reason for your hair loss or thinning is important in determining what products might be helpful," she says.

If you are in need of a thickening or growing agent regardless of the source of hair thinning, Rogaine is the most effective hair growth treatment on the market, according to both Herrmann and Mizuguchi. "Although we don’t fully understand the exact mechanism behind Rogaine, studies have shown that it lengthens the hair’s growing phase and restores the size of shrunken follicles," says Herrmann. "This leads to gradual re-thickening of hair."

How Do I Know If I Have a Vitamin Deficiency?

Vitamins and minerals do play a role in hair health, and vitamin deficiency can be behind hair loss. There are quite a few signs that can give clues if someone has a severe vitamin deficiency. To get a better idea, Herrmann broke down a few common deficiencies and what they may cause. According to Herrmann:

Vitamin C deficiency: This causes hair-splitting, bleeding gums, nosebleeds, poor wound healing, and problems fighting infections.

Niacin deficiency: Can cause a scaly rash on sun-exposed skin, headaches, vomiting and diarrhea, fatigue, and depression.

Vitamin A deficiency: This can cause dry skin, dry eyes, night blindness, delayed growth, and breakouts.

"Vitamin deficiencies can be detected through blood work. They are uncommon except in those following strict diets, including vegan diets," Herrmann explains. "Vegans may need to supplement to make sure they obtain adequate amounts of vitamins that come from animal products. Also, strict sun avoidance can put someone at higher risk for vitamin D deficiency."

What Are Some Ways to Make My Hair Grow?

Even though hair supplements are likely not your best bet, there are things you can do to help grow stronger, healthier strands.

Eat Foods Rich in Fatty Acids

Herrmann says eating foods rich in omega-3 fatty acids, like salmon, "can also help dry, damaged hair by adding luster, elasticity, and shine to dull locks."

Try a Multivitamin

Nature Made Women's Multivitamin Tablets
Nature Made Women's Multivitamin Tablets $8
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Herrmann says that taking vitamins B6, B12, and folate may be helpful for hair growth. Remember to see a doctor before taking any sort of supplement.

Use a Thickening Shampoo

Not Your Mother's Way To Grow Long & Strong Conditioner
Not Your Mother's Way to Grow Long & Strong Shampoo $8
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Fortified with vitamins, herbs, and bioactive ingredients, this shampoo is meant to strengthen hair and promote healthy hair growth.

The Final Takeaway

Ultimately, there is little to support the efficacy of hair supplements. Those looking to treat thinning hair are better off going to their doctor and finding out what's causing the hair loss, and how it can be treated. While it is possible that a vitamin deficiency is behind thinning or less than lustrous locks, a balanced and healthy diet can help improve the condition of your strands.

Article Sources
Byrdie takes every opportunity to use high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial guidelines to learn more about how we keep our content accurate, reliable and trustworthy.
  1. Phillips TG, Slomiany WP, Robert Allison II. Hair loss: common causes and treatmentAFP. 2017;96(6):371-378.

  2. Almohanna HM, Ahmed AA, Tsatalis JP, Tosti A. The role of vitamins and minerals in hair loss: a reviewDermatol Ther (Heidelb). 2018;9(1):51-70.

  3. Burns EK, Perez-Sanchez A, Katta R. Risks of skin, hair, and nail supplementsDermatol Pract Concept. 2020;10(4):e2020089.

  4. Almohanna HM, Ahmed AA, Tsatalis JP, Tosti A. The role of vitamins and minerals in hair loss: a reviewDermatol Ther (Heidelb). 2018;9(1):51-70.

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