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The Best Vitamins for Hair Growth

So, in this article, I intend to provide some facts to categorize those nutraceuticals with varying degrees of effectiveness.


Gene Bruno

Aug 4, 2021

I’m frequently asked the question: “What vitamins are good for hair growth?” or “How do I increase my hair growth” or some variation on that theme. Unfortunately, there is a great deal of misinformation about this topic – not to mention false promises. So, in this article, I intend to provide some facts to categorize those nutraceuticals with varying degrees of effectiveness.

Mildly Effective Nutraceuticals

Vitamin A for hair: Vitamin A protects hair follicle cells from damage caused by free radicals.[1] Vitamin A deficiency causes dry hair, while taking large amounts can cause hair loss. All in all, supplementation is not likely to have a significant impact on your hair.

Vitamin E for hair: vitamin E is beneficial for hair because it helps to maintain the integrity of cell membranes of hair follicles. This vitamin provides physical stability to cell membranes and acts as an antioxidant.[2] Supplementation is not likely to have a significant impact on your hair.

Vitamin C for hair: One of the primary functions of Vitamin C is to help product and maintain healthy collagen, the connective tissue found within hair follicles. Vitamin C is also a potent antioxidant and protects both the cells found within follicles and cells in nearby blood vessels.[3] Once again, supplementation is not likely to have a significant impact on your hair.

Moderately Effective Nutraceuticals

Biotin for hair: Biotin is required for several enzymatic reactions within the body, and is necessary for the proper metabolism of protein, fat, and carbohydrates.[4] Over time, poor metabolism of nutrients can contribute to undernourished hair follicle cells. Although rare, a biotin deficiency results in skin rashes and hair loss. A study conducted at Harvard University suggests that biotin is one of the most important nutrients for preserving hair strength, texture, and function.[5]

Vitamin B for hair: B Vitamins are important for hair growth. Reduced levels of niacin and pantothenic acid can contribute to the undernourishment of hair follicle cells. [6] Research using these nutrients in combination with keratin protein demonstrated improvements in hair growth and thickness.

Very Effective Nutraceuticals

The predominant protein in hair is keratin. Consequently is would seem to make sense that supplementation with keratin would help support the structure of keratin in human hair — and indeed, that is the case as was demonstrated in two clinical studies with solubilized keratin (as Cynatine® HNS). In the first study, daily supplementation with solubilized keratin was tested in women with damaged, fragile and stressed hair as a consequence of internal (stress, genetic) and external (styling, aggressive treatments, UV exposure) causes. The result of supplementation was a significant reduction in hair loss during washing.[7] Hair was significantly stronger, and clinical evaluation and self-assessment of hair brightness were also improved. In conclusion, solubilized keratin promoted a higher resistance to stress and mechanical actions (combing, brushing, washing, etc.), counteracted excessive hair loss, strengthening the hair and improving its ultra-structure and hair brightness.

In the second study, supplementation with solubilized keratin improved various aspects of hair and nails in women tested.[8] This included:

  • 34.4% reduction in hair loss (from combing, brushing, washing, etc.)

  • Significant increase in hair growth

  • Significant improvement in hair strength

  • Significant improvement in hair appearance (brightness, color, etc.)

  • Considerable improvement in the tendency of nails to break and a substantial improvement in nail appearance

In these studies, subjects included 500mg of solubilized keratin, along with 15mg zinc, 18mg niacinamide, 1.65mg copper, 13.68mg pantothenic acid, 2mg vitamin B6, and 300mcg biotin. These nutraceuticals can be found in these doses in Reserveage Keratin Hair Booster. It should be noted that all these nutraceuticals should be ingested as dietary supplements. There is no evidence detailing that using them topically in, a keratin shampoo, would have any benefit whatsoever.


[1] Ross A, Ternus M. Vitamin A as a hormone: Recent advances in understanding the actions of retinal, retinoic acid, and beta-carotene. J Am Dietetic Assoc. 1993;93:1285–1290.[2] Niki E, Noguchi N, et. al. Interaction among vitamin C, vitamin E, and B-carotene. Am J Clin Nutr. 1995;62(supplement):1322S–1326S.[3] Niki E. Action of ascorbic acid as a scavenger of active and stable oxygen radicals. Am J Clin Nutr. 1991;54(suppl):1119S–1124S.[4] Knowles J. The mechanism of biotin-dependent enzymes. Annu Rev Biochem 1989;58:195–221.[5] Doss L. Hair breakthrough offers hope to millions. J Longevity. 2000;6:4:18–20.[6] Janowiak JJ, Ham C. A practitioner’s guide to hair loss. Part 2―Diet, supplements,vitamins, minerals, aromatherapy, and psychosocial aspects. Alternative & Complementary Therapies. August 2004;10(4):200-205.[7] Marzatico F, Quaglini M, Michelotti A. Evaluation of the efficacy of a food supplement to strengthen and support hair growth. Unpublished Study. Unpublished. Farcoderm srl. Head office: Via Angelini angolo Via dalla Chiesa – 27028 San Martino Siccomario – Pavia; 2010:17 pgs.[8] Beer C, Wood S, Veghte RH. A Clinical Trial to Investigate the Effect of Cynatine HNS on Hair and Nail Parameters.The Scientific World Journal. 2014; 2014, Article ID 641723:6 pgs.