Nutritional Supplements With Evidence to Restore Hair Loss

People’s identity is tied to their appearance, which makes significant hair loss at any age or gender devastating, but can nutritional supplements help?

Those experiencing different types of hair loss are often desperate to find a solution, and there is no shortage of lotions, potions, and pills promising new hair growth. Are these safe and effective, or are they simply “snake oil”? This article is about evidence-based nutritional supplements that may help restore hair loss, depending on its cause. It’s important to keep in mind that nutrient needs between people differ, so supplementation is not one-size-fits-all.

Androgenic Alopecia

Androgenic alopecia is commonly known as “male pattern baldness” or “female pattern baldness,” and the leading cause of it is an androgenic hormone known as dihydrotestosterone (DHT). DHT binds to the hair follicle, causing it to shrink, and eventually, the hair stops growing entirely. Some nutritional supplements positively affect DHT and help support hair growth, but many “hair growth nutritional supplements” contain ingredients for which evidence of benefit is lacking.

A study at an alopecia clinic [1] found that 81% of the patients were female, and 63% of them used nutritional supplements, compared to the US average of 40% [2]. The most common hair loss supplements used include biotin, vitamin B12, and B-complex multivitamin and while taking these nutritional supplements may seem benign, biotin, for example, is well-known to interfere with diagnostic tests for Thyroid Stimulating Hormone (TSH). The implication of this is that people taking biotin-containing supplements to self-treat hair loss without first being evaluated for a thyroid disorder may result in missing the diagnosis and underlying cause of their hair loss. In addition to interfering with diagnostic tests, some ‘hair loss nutritional supplements’ may be toxic in high doses, while still others may interact with medications, or supplements that people are taking to restore a diagnosed nutrient deficiency [3]. 

A systematic review that was recently published in the Journal of the American Medical Association (JAMA) Dermatology (November 30, 2022) evaluated the effectiveness of nutritional supplements for treating hair loss in people without nutritional deficiency [4]. This first article is based on this current systematic review.

Three Main Types of Hair Loss

There are three main types of hair loss, telogen effluvium, androgenic alopecia (AGA), and alopecia areata (AA).

Telogen effluvium (TE) is the most common form of diffuse hair loss [5] and usually occurs after a profound stress, shock or traumatic event including childbirth,  a thyroid disorder, or rapid weight loss. This type of hair loss was covered in this earlier article. But TE is not the only type of hair loss in hypothyroidism. In a study of more than 1200 people with thyroid disorder, half (50%) of people aged 40 years old and older had either alopecia areata, or androgenetic alopecia [6].

Androgenic alopeciaAndrogenic alopecia (AGA) affects up to 50% of men and women. In men is called ‘male pattern baldness’ and is mainly seen on the crown of the head and the temples. In women, it is called ‘female pattern baldness’ and is primarily seen at the crown of the head, with a broader center part. Androgenic alopecia is a genetic disorder that involves both maternal (mother’s) and paternal (father’s) genes, with sons being 5-6 times more likely to have it if their fathers were balding [7]. 

Alopecia areataAlopecia areata (AA) is an autoimmune disorder where the body’s immune system attacks the follicles. As a result, hair often comes out in clumps, usually the size and shape of a quarter, but it can affect more expansive areas of the scalp [8]. It can occur in those with other autoimmune conditions, including thyroid disease. 

There are medication treatments available for the different types of hair loss, and there is increasing evidence that taking specific nutritional supplements can be helpful in helping restore hair loss.

A systematic review published in JAMA Dermatology [4] published November 30, 2022 — just a month ago, evaluated the effectiveness of nutritional supplements for treating hair loss in people without nutritional deficiency. The dietary supplements with the highest-quality evidence of potential benefit were categorized according to their mechanism of action and are outlined in this article.

Dihydrotestosterone (DHT) as a Main Cause of Hair Loss

One of the main contributors to androgenetic alopecia (AA) is the male hormone (androgen) called dihydrotestosterone (DHT). DHT is made by an enzyme called 5 alpha-reductase (5-AR) acting on testosterone. When DHT binds to the receptors in the oil glands of hair follicles, it causes the follicles to shrink, shortening their life span. Eventually, these follicles shrink so much that they stop producing hair. The end result is baldness. DHT can be suppressed by medications such as Finasteride®, which lowers levels of DHT. This reduces the attack on hair follicles, slowing or stopping hair loss.

(Minoxidil® is a hair loss medication that works by an entirely different mechanism. It acts as a vasodilator, increasing blood flow in the scalp by making blood vessels wider. It is thought that this increased blood flow slows hair loss and encourages hair to regrow.)

[Update, December 29, 2022: While androgens such as DHT contribute to baldness by their detrimental effect on hair follicles in the scalp, androgens like DHT are also a key player in hair growth. This contradictory role of androgens is known as the “androgen paradox”. This short supplemental article explains more. ]

Nutritional Supplements – the role of 5-α reductase (5-AR) inhibitors in restoring hair loss

Pumpkin Seed Oil as a nutritional supplement in hair loss

nutritional supplements - Pumpkin seedsPumpkin seed oil is known to be effective in treating benign prostate hyperplasia (BPH) because it acts as a 5AR inhibitor [9,10], so it was an excellent candidate to study for its effect on hair growth. In a 2014 study, 76 male androgenic alopecia (AGA) patients were divided into two groups. For 24 weeks, one group of subjects took a 400 mg capsule of pumpkin seed oil each day, while the other group took a placebo. The group taking the pumpkin seed oil nutritional supplement showed significantly superior hair growth, with a mean hair count increase of 40% in the pumpkin seed oil-treated men compared to 10% in the placebo-treated men. There were no differences in adverse effects between the two groups.

Nutritional Supplements in Hair Loss – Saw Palmetto

nutritional supplements -Saw PalmettoIn a 2004 pilot study, six of ten subjects (60%) that took an extract made from 200 mg Saw Palmetto extract (Serenoa repens), 50 mg betasitosterol, along with 50 mg lecithin, 100 mg inositol, 25 mg phosphatidyl choline, 15 mg niacin, and 100 μg biotin for 5 months were reported to have improved hair growth compared to the placebo controlled group (11%), however the difference was not statistically significant [11]. Studies with larger groups of both treatment and control groups is needed before conclusions can be made. Most importantly, it is hard to know if the benefits were due to the Saw Palmetto, or some of the other ingredients in the supplement.  For this reason, I think this next study is more helpful.

A two year randomized control study of 100 male patients with mild to moderate androgenic alopecia took either 320 mg of dry Saw Palmetto nutritional supplement extract (Serenoa repens) daily for 24 months, or 1 mg Finasteride daily for the same time period.  While Finasteride was significantly more effective at slowing hair loss, at 24-months the Saw Palmetto extract did stabilize hair loss. [12].

The results of this study suggest that Saw Palmetto can stabilize hair loss over two years, but is less effective than the medication Finasteride.

The Role of Specific Micronutrients in Restoring Hair Loss

Nutritional Supplements for Hair Loss – Vitamin D

Three studies from the last 5-10 years have demonstrated that that lower levels of vitamin D, or vitamin D deficiency have been associated with all three forms of hair loss, including androgenic alopecia [13], alopecia areata [14], and telogen effluvium [15].

A small 2021 study supplemented 40 women with telogen effluvium with very high oral vitamin D3 (200,000 IU every two weeks for six weeks). The study reported that more than 80% had improved results on a hair pull test after six months, with no adverse side effects [16]. However, the limitation of this study was that it was unknown if any of these subjects were deficient in vitamin D before taking the supplements, there was no control group, and telogen effluvium tends to resolve by itself over the same six-month period without treatment.

nutritional supplements - vitamin D capsulesBefore beginning supplementation, it would be prudent to assess vitamin D status and to determine how low or deficient it is, then increase dietary intake of vitamin D, and supplement as necessary to attain and maintain sufficient blood levels of vitamin D.

nutritional supplements - salmon as a source of vitamin DFoods that are naturally good sources of vitamin D include fatty fish such as salmon, mackerel and tuna.

Nutritional Supplements for Hair Loss – Zinc

A deficiency of zinc is associated with telogen effluvium, and lower zinc levels have been observed in people with alopecia areata (AA) [17-19]. Two small studies of zinc supplementation in patients with alopecia areata both reported benefits. The first study with 38 subjects was from 1981 [20] and supplemented using 220 mg of zinc sulfate per day. The second study from 2012 [21] had 67 subjects supplemented with 5 mg/kg body weight per day of zinc sulfate. Both studies reported benefits at three months; however, larger studies are needed.

It would be best to assess zinc status for those with hair loss (especially alopecia areata) prior to supplementing with zinc.

sea urchin roe as a source of zincIf zinc status is low, increasing dietary intake of zinc would be a great place to start. Good sources of zinc include red meat, poultry, seafood such as oysters, crab, lobster, and sea urchin (uni, in Japanese), as well as nuts.

If needed to achieve adequate blood levels of zinc, a supplement can be added to attain, and maintain zinc adequacy, but it’s important to ensure there is adequate copper intake as well, as zinc depletes copper. Beef liver is a very good source of dietary copper, but eating 3 or 4 ounces once a week may be enough, as it has 6 times the recommended dietary intake of copper, and high amounts of preformed vitamin A. It is also important not to take zinc supplements within several hours of taking iron supplements, as they complete for binding sites.

Nutritional Supplements for Hair Loss – Vitamin B12

Vitamin B12 is necessary for DNA synthesis and it was proposed in a 2017 report on the role of micronutrients in alopecia areata that vitamin B12 could be helpful in increasing the number of hair follicles [17].

A 2018 study of people with telogen effluvium that included symptoms of itching, pain, soreness, and/or burning were evaluated for symptoms of B12 deficiency. While lab normal values were 200-400 pg/mL, deficiency was evaluated to be <550 pg/ml, a cutoff limit reported to be used in other countries. After four months, 90% of subjects that received either a daily B12 tablet or monthly B12 injection had significant decrease or even an absence of hair shedding [23]. The main shortcoming of this study was the self-resolving nature of telogen effluvium — which means that over the same period of time, doing nothing could have resulted in improvement is hair loss.

nutritional supplements - liver as a source of vitamin B12The best dietary sources of vitamin B12 are organ meats, including liver and kidney, clams, sardines, and beef, however, some disorders and advanced age can result in reduced dietary absorption of vitamin B12. Testing vitamin B12 status is important especially in older adults who have decreased absorption of B12 due to decreased intrinsic factor, as well as testing B12 status in those taking medication to lower stomach acid. 

Nutritional Supplements – the role of antioxidants in restoring hair loss

Oxidative stress has been thought to play a role in all three types of hair loss [24-26] and antioxidants such as selenium, vitamins A, E and C, and carotenoids (yellow, orange or red coloured fat-soluble pigments found in vegetables, fruit, and some fish. 

A 2015 randomized control study compared the effects of giving a supplement containing omega 3 fat from fish, omega 6 fat from blackcurrant seed oil, as well as the antioxidants lycopene (from tomato), vitamin C, and vitamin E versus giving no supplement to 188 women diagnosed with stage 1 androgenic alopecia [27]. The intervention group had significantly increased hair density and hair thickness at six months.

A 2010 randomized control study compared giving a supplement containing mixed tocotrienol from the vitamin E family versus a placebo to patients with unspecified hair loss. The 50 mg mixed capsules given to the intervention group had 30.8% alpha-tocotrienol, 56.4% gamma-tocotrienol, and 12.8% delta-tocotrienol, as well as 23 IUs alpha-tocopherol). Twenty one subjects were randomly assigned receive 2 x 50 mg (100 mg) of mixed tocotrienols daily, while 17 subjects were assigned to receive an oral placebo capsule. At 8-months, the number of hairs of the subjects in the intervention group increased by 34.5% compared to the placebo group which had a 0.1% decrease [28]. The shortcomings of this study were the small sample size and that the study did not define hair loss in the inclusion criteria of subjects. 

Nutritional Supplements – more is not always better

Caution needs to be taken when choosing types and amounts of antioxidant supplements as excessive use of supplements such as selenium, for example has been tied both to toxic effects and hair loss [29]. Even when getting selenium in the diet by eating Brazil nuts, only 2 is already at the maximum daily amount. Eating 4 or 5 Brazil nuts can exceed the safe upper tolerance of selenium for adults, so more is not better. 

Excess vitamin A intake can result in vitamin A intoxication which can result in seizures or blurred vision, and long term (chronic) over supplementation with vitamin A can result in several symptoms, including muscle and bone pain, high blood lipids and ironically alopecia, or hair loss [30].

nutritional supplements - cod livers as a source of vitamin AThe best sources of preformed vitamin A (retinol) are beef liver, fish, and eggs and a delicious and very rich source is Icelandic cod livers.

Cod livers are very high in retinol, and just half a 115g can contains 450% the recommended daily intake for vitamin A. To avoid getting too much preformed vitamin A, it is best not to eat cod livers more than once every week or two, and even further apart if also regularly consuming beef liver which is also high in preformed vitamin A.

Before beginning to take supplements it is important to assess intake form food sources, so as not to take too much as a supplement.

Other Nutritional Supplements – probiotics and growth hormone modulators

kim chee as a probioticProbiotics have been hypothesized to improve blood flow to the scalp and one study from 2020 used a kimchi and fermented soybean paste (cheonggukjang) probiotic product.

Twenty-three men and twenty-three women with androgenic alopecia (AGA) were given the supplement and at four months, 93% showed significant improvement in either hair thickness and/or hair count, with no serious side effects [31]. The limitations of this study were the small sample size and lack of a control group.

capsaicin Capsaicin, is the chemical that give hot chilis their spiciness and is used as a topical pain reliever. When  applied to the scalp has been found to increase Insulin-like Growth Factor I (IGF-1) which is involved in hair growth [32].

A randomized control study of a capsaicin and isoflavone supplement (6 mg capsaicin, 75 mg isoflavone (from soy) in 48 adults with either androgenic alopecia (AGA) or alopecia areata (AA) compared to controls found significantly more hair growth in the capsaicin and isoflavone group at 5 months, and no adverse effects were reported. The limitations of this study were its small sample size as well as the inclusion of various types of alopecia.

Final Thoughts…

In the United States, dietary supplements are normally considered a food and as such, their safety or effectiveness are not evaluated by the Food and Drug Administration (FDA). It is only if a product is labelled to treat a disease that the product meets the definition of a drug and needs to establish its efficacy [33].

In Canada, however, dietary supplements are considered Natural Health Products (NHP) by Health Canada and are treated as non-prescription drugs which are regulated under the Natural Health Product Regulations. According to Health Canada, in the ten years from 2004 (when the Natural Health Product Regulations came into existence) and 2014, nearly 55,000 licenses for NHPs were issued [34].

The ease by which Canadians can order supplements online from the US essentially bypasses any governmental safeguards put into place by Health Canada so it is important that people in both countries are aware that there is no FDA oversight for safety or efficacy for supplements purchased from the US. For this reason, it is best that before people begin using dietary supplements to self-treat hair loss, that they discuss this with a knowledgeable healthcare professional, such as their doctor or Registered Dietitian. In addition, for those already taking dietary supplements, it is important before going for lab tests to mention to your doctor and Dietitian which supplements you are taking so that they can ensure that you discontinue use of specific supplements for an sufficiently long period of time before the test (such biotin before a Thyroid Stimulating Hormone (TSH) test).

More Info?

Hair loss can be devastating, but before parting with substantial sums for money for lotions, potions, or pills that promise new hair growth, first take the time to find out what you need. 

Consider finding out if your diet or lifestyle may put you at risk for nutrient deficiencies, and if so to have those evaluated. Ask yourself if it is possible you may have a thyroid disorder (this article may help) so that you can have diagnostic tests before taking supplements that can interfere with getting accurate results.

Finally, if blood tests come back indicating that you may have low nutrient status or a deficiency, find out which nutrients can be adequately obtained from food, and which may need to be supplemented.

Nutritional supplements can be very helpful if used correctly, but taken in the wrong dosage, or at the wrong timing, supplements can interfere with the absorption of medications you may take, and/or with other nutrients you are already low on.

If you would like more information on how I can help assess your dietary intake or nutrient status of specific nutrients, please send me a note through the Contact Me form at the top of this page.

To your good health!


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    1. Burns LJ, Senna MM. Supplement use among women experiencing hair loss. Int J Womens Dermatol. 2020;6(3):211. doi:10.1016/j.ijwd.2020.01.002
    2. E.D. Kantor, C.D. Rehm, M. Du, E. White, E.L. Giovannucci, Trends in dietary supplement use among U.S. adults from 1999–2012, JAMA, 316 (14) (2016), pp. 1464-1474
    3. Ronis MJJ, Pedersen KB, Watt J. Adverse effects of nutraceuticals and dietary supplements. Annu Rev Pharmacol Toxicol. 2018;58:583-601. doi:10.1146/annurev-pharmtox-010617-052844
    4. Drake L, Reyes-Hadsall S, Martinez J, Heinrich C, Huang K, Mostaghimi A. Evaluation of the Safety and Effectiveness of Nutritional Supplements for Treating Hair LossA Systematic ReviewJAMA Dermatol. Published online November 30, 2022. doi:10.1001/jamadermatol.2022.4867
    5. Malkud S. Telogen Effluvium: A Review. J Clin Diagn Res. 2015;9(9):WE01-WE3. doi:10.7860/JCDR/2015/15219.6492
    6. Vincent M, Yogiraj K. A descriptive study of alopecia patterns and their relation to thyroid dysfunction. Int J Trichol 2013;5:57-60
    7. Ho CH, Sood T, Zito PM. Androgenetic Alopecia. Updated Nov 15, 2021. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing,
    8. Medical News Today, Alopecia areata: Causes, diagnosis and treatments, April 7, 2022,
    9. Hong H, Kim CS, Maeng S. Effects of pumpkin seed oil and saw palmetto oil in Korean men with symptomatic benign prostatic hyperplasia. Nutr Res
      Pract. 2009;3(4):323-327. doi:10.4162/nrp.2009.3.
    10. Cho YH, Lee SY, Jeong DW, et al. Effect of pumpkin seed oil on hair growth in men with androgenetic alopecia: a randomized, double-blind, placebo-controlled trial. Evid Based Complement Alternat Med. 2014;549721. doi:10.1155/2014/549721
    11. Prager N, Bickett K, French N, Marcovici G. A randomized, double-blind, placebo-controlled trial to determine the effectiveness of botanically
      derived inhibitors of 5-alpha-reductase in the treatment of androgenetic alopecia. J Altern Complement Med. 2002;8(2):143-152. doi:10.1089/
    12. Rossi A, Mari E, Scarno M, et al. Comparative effectiveness of finasteride vs Serenoa repens in male androgenetic alopecia: a two-year study. Int J
      Immunopathol Pharmacol. 2012;25(4):1167-1173. doi:10.1177/039463201202500435
    13. Banihashemi M, Nahidi Y, Meibodi NT, Jarahi L, Dolatkhah M. Serum vitamin D3 level in patients with female pattern hair loss. Int J Trichology. 2016;
      8(3):116-120. doi:10.4103/0974-7753.188965
    14. Rasheed H, Mahgoub D, Hegazy R, et al. Serum ferritin and vitamin D in female hair loss: do they play a role? Skin Pharmacol Physiol. 2013;26(2):101-107. doi:10.1159/000346698
    15. Lee S, Kim BJ, Lee CH, Lee WS. Increased prevalence of vitamin D deficiency in patients with alopecia areata: a systematic review and
      meta-analysis. J Eur Acad Dermatol Venereol. 2018;
      32(7):1214-1221. doi:10.1111/jdv.14987
    16. Sattar F, Almas U, Ibrahim NA, et al. Efficacy of oral vitamin D3 therapy in patients suffering from diffuse hair loss (telogen effluvium). J Nutr Sci
      Vitaminol (Tokyo). 2021;67(1):68-71. doi:10.3177/jnsv.67.68
    17. Thompson JM, Mirza MA, Park MK, Qureshi AA, Cho E. The Role of micronutrients in alopecia areata: a review. Am J Clin Dermatol. 2017;18(5):
      663-679. doi:10.1007/s40257-017-0285-x
    18. Abdel Fattah NS, Atef MM, Al-Qaradaghi SM. Evaluation of serum zinc level in patients with newly diagnosed and resistant alopecia areata. Int J
      Dermatol. 2016;55(1):24-29. doi:10.1111/ijd.12769
    19. Mussalo-Rauhamaa H, Lakomaa EL, Kianto U, Lehto J. Element concentrations in serum, erythrocytes, hair and urine of alopecia patients.
    20. Ead RD. Oral zinc sulphate in alopacia areata-a double blind trial. Br J Dermatol. 1981;104(4): 483-484. doi:10.1111/j.1365-2133.1981.tb15323.x
    21. Sharquie KE, Noaimi AA, Shwail ER. Oral zinc sulphate in treatment of alopecia areata (double blind; cross-over study). J Clin Exp Dermatol Res.
    22. Siavash M, Tavakoli F, Mokhtari F. Comparing the effects of zinc sulfate, calcium pantothenate, their combination and minoxidil solution regimens
      on controlling hair loss in women: a randomized controlled trial. J Res Pharm Pract. 2017;6(2):89-93. doi:10.4103/jrpp.JRPP_17_17
    23. Daly T, Daly K. telogen effluvium with dysesthesia (ted) has lower B12 levels and may respond to B12 supplementation. J Drugs Dermatol.
    24. Prie BE, Iosif L, Tivig I, Stoian I, Giurcaneanu C. Oxidative stress in androgenetic alopecia. J Med Life. 2016;9(1):79-83.
    25. Savci U, Senel E, Oztekin A, Sungur M, Erel O, Neselioglu S. Ischemia-modified albumin as a possible marker of oxidative stress in patients with
      telogen effluvium. An Bras Dermatol. 2020;95(4): 447-451. doi:10.1016/j.abd.2020.01.005
    26. Öztürk P, Arıcan Ö, Kurutaş EB, Mülayim K. Oxidative stress biomarkers and Adenosine deaminase over the alopecic area of the patients with alopecia areata. Balkan Med J. 2016;33(2):188-192. doi:10.5152/balkanmedj.2016.16190
    27. Le Floc’h C, Cheniti A, Connétable S, Piccardi N, Vincenzi C, Tosti A. Effect of a nutritional supplement on hair loss in women. J Cosmet
      Dermatol. 2015;14(1):76-82. doi:10.1111/jocd.12127
    28. Beoy LA,WoeiWJ, Hay YK. Effects of tocotrienol supplementation on hair growth in human volunteers. Trop Life Sci Res. 2010;21(2):
    29. Sutter ME, Thomas JD, Brown J, Morgan B. Selenium toxicity: a case of selenosis caused by a nutritional supplement. Ann Intern Med. 2008;148
      (12):970-971. doi:10.7326/0003-4819-148-12-200806170-00015
    30. Olson JM, Ameer MA, Goyal A. Vitamin A Toxicity. [Updated 2022 Aug 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-.
    31. Park DW, Lee HS, Shim MS, Yum KJ, Seo JT. Do kimchi and cheonggukjang probiotics as a functional food improve androgenetic alopecia? a clinical pilot study. World J Mens Health. 2020;38 (1):95-102. doi:10.5534/wjmh.180119
    32. Harada N, Okajima K. Effect of topical application of capsaicin and its related compounds on dermal insulin-like growth factor-I levels in mice
      and on facial skin elasticity in humans. Growth Horm IGF Res. 2007;17(2):171-176. doi:10.1016/j.ghir. 2006.12.005
    33. US Food and Drug Administration. Questions
      and Answers on Dietary Supplements. Accessed December 27, 2022.
    34. Health Canada, Natural Health Products Program Quarterly Snapshot – Quarter 1 (Fiscal year 2014-2015),


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