The Effects of the Oral Supplementation with a Natural Keratin Hydrolysate (Kera-Diet®) on Hair and Nails: Randomized, Placebo and Benchmark-Controlled Clinical Trial on Healthy Females
DOI:
https://doi.org/10.17140/TCOJ-4-115Keywords:
Keratin hydrolysate, Oral supplementation, Telogen effluvium, Hair growth, Brittle nail syndrome, Onychoschizia, Clinical studyAbstract
Background
Telogen effluvium (TE) and its acute form (aTE) are two of the commonest occurrences in a trichology clinic, with patients claiming excessive hair shedding. ATE can occur in people of any age and ethnicity and is considered to be a quite common condition in either sex even if women are more likely to have a lowered quality of life and restricted social contacts as compared to men as a result of hair loss. Brittle nail syndrome (BNS) is a common condition affecting up to 20% of the population, especially women over 50 years of age. Nails affected by BNS appear ragged, thin, and dull. The clinical features of BNS include horizontal splits within the nail plate (onychoschizia) and increased longitudinal ridging or splitting (onychorrh exis). In BNS oral supplementation, trace elements and amino acids (especially L-Cystine) have been reported to be useful to ameliorate the nail plate condition.
Objective
We hypothesized that a nutritional approach, with nutrients of which the composition is close to the human keratin, could be effective to decrease hair loss during telogen effluvium and to improve brittle nails condition. At this purpose, a clinical study was designed to investigate the efficacy of a natural keratin hydrolysate obtained from a non-human source (feathers) on both aTE and BNS.
Methods
The in vivo effects of a natural keratin hydrolysate, Kera-Diet® (KD) upon human hair and nails condition was tested in a randomized, double-blind, parallel-group, benchmark (BE) and placebo (PL) controlled study involving 60 women during 90 days. In all subjects, Anagen/Telogen hair, hair volume and density, pull test, global photography, hair and nails brightness, and nail plate growth were measured at baseline and after 45 and 90 days of products use. A self-assessment test was carried out at the end of the study.
Results
With the KD treatment group, hair density, percentage of hair in anagen phase, hair and nails brightness, and nails growth were significantly increased compared to PL treatment group. Interestingly, with this same group, the diagnosis of aTE by pull testing was negative from 45 days. The efficacy of KD was equal to or greater than PL treatment group.
Conclusion
In this study, we demonstrated that daily oral administration of 1000 mg during 3 months of a natural extensively keratin hydrolysate, Kera-Diet®, associated to trace elements and specific vitamins was effective to improve both hair and nails condition. Furthermore, it demonstrates the role of nutrients in both aTE and BNS.
References
2017 CRN consumer survey on dietary supplements. The sci-ence behind the supplements. Council for Responsible Nutrition. Web site. https://www.crnusa.org/newsroom/dietary-supple-ment-usage-increases-says-new-survey. Accessed November 18, 2020.
Katta R, Huang S. Skin, hair and nail supplements: An evidence-based approach. Skin Therapy Lett. 2019; 24(5): 7-13.
Dini I, Laneri S. Nutricosmetics: A brief overview. Phytother Res. 2019; 33(12): 3054-3063. doi: 10.1002/ptr.6494
Bauer K, Clearfield W, Ramacher R, Ling P-R, Marsland C, Bell SJ. Nutrient-dense, functional foods enhance hair, skin, and nail appearance. Trichol Cosmetol Open J. 2020; 2(1): 1-6. doi: 10.17140/ TCOJ-1-114
Nobile V, Duperray J, Cestone E. Sergheraert R., Tursi F. Ef-ficacy and safety of L-Cystine associated or not to a natural keratin (Kera-Diet®) hydrolysate on hair and nails: Randomised, placebo controlled, clinical trial on healthy females. Effects of Cos-metics and Food Supplements on Skin. 2019; 5: 1. doi: 10.4172/2471- 9323.1000142
Hornfeldt CS. Growing evidence of the beneficial effects of a marine protein-based dietary supplement for treating hair loss. J Cosmet Dermatol. 2018; 17(2): 209-213. doi: 10.1111/jocd.12400
Beer C, Wood S, Veghte RH. A clinical trial to investigate the effect of Cynatine HNS on hair and nail parameters. Scientific World Journal. 2014; 2014: 641723. doi: 10.1155/2014/641723
Etemadian Y, Ghaemi V, Shaviklo AR, Pourashouri P, Mahoon-ak ARS, Rafipour R. Development of animal/ plant-based protein hydrolysate and its application in food, feed and nutraceutical in-dustries: State of the art. Journal of Cleaner Production. 2021; 278: 123219. doi: 10.1016/j.jclepro.2020.123219
Cash T. The psychology of hair loss and its implications for pa-tient care. Clin Dermatol. 2001; 19(2): 161-166. doi: 10.1016/s0738- 081x(00)00127-9
Williamson, D, Gonzalez M, Finlay AY. The effect of hair loss on quality of life. J Eur Acad Dermatol Venereol. 2001; 15(2): 137- 139. doi: 10.1046/j.1468-3083.2001.00229.x
DonkVJ, Passchier J, Knegt-Junk C. Psychological character-istics of women with androgenetic alopecia: A controlled study. Br J Dermatol. 1991; 125: 248-252. doi: 10.1111/j.1365-2133.1991. tb14749.x
Reid EE, Haley AC, Borovicka JH. Clinical severity does pre-dict not reliably quality of life in women with alopecia areata, telo-gen effluvium, or androgenic alopecia. J Am Acad Dermatol. 2012; 66: e97-e102. doi: 10.1016/j.jaad.2010.11.042
Asghar F, Shamim N, Farooque U, Sheikh H, Aqeel R. Telogen effluvium: A review of the literature. Cureus. 2020; 12(5): e8320. doi: 10.7759/cureus.8320
Harrison S, Sinclair R. Telogen effluvium. Clin Exp Dermatol. 2002; 27: 389-395. doi: 10.1046/j.1365-2230.2002.01080.x
Hughes EC., Saleh D. Telogen Effluvium. In: StatPearls. Trea-sure Island (FL), USA: StatPearls Publishing; 2020.
Sant'Anna Addor FA, Donato LC, Melo CSA. Comparative evaluation between two nutritional supplements in the improve-ment of telogen effluvium. Clin Cosmet Investig Dermatol. 2018; 11: 431-436. doi: 10.2147/CCID.S173082
Udompanich S, Chanprapaph K, Suchonwanit P. Hair and scalp changes in cutaneous and systemic lupus erythematosus. Am J Clin Dermatol. 2018. 19(5): 679-694. doi: 10.1007/s40257-018-0363-8
Saleh D, Nassereddin A, Cook C. Anagen Effluvium. In: Stat-Pearls. Treasure Island (FL), USA: StatPearls Publishing; 2020.
Motosko CC, Bieber AK, Pomeranz MK, Stein JA, Martires Submit your article to this journal | https://openventio.org/submit-manuscript/ KJ. Physiologic changes of pregnancy: A review of the litera-ture. Int J Womens Dermatol. 2017; 3(4): 219-224. doi: 10.1016/j. ijwd.2017.09.003
Belyayeva E, Gregoriou S, Chalikias J, Kontochristopoulos G, Koumantaki E, Makris M, et al. The impact of nail disorders on quality of life. Eur J Dermatol. 2013; 23(3): 366-371. doi: 10.1684/ ejd.2013.2048
Kerkhof PC, Pasch MC, Scher RK. Brittle nail syndrome: A pathogenesis-based approach with a proposed grading system. J Am Acad Dermatol. 2005; 53: 644-651. doi: 10.1016/j.jaad.2004.09.002
Chessa MA, Iorizzo M, Richert B, López-Estebaranz JL, Rigop-oulos D, Tosti A, et al. Pathogenesis, clinical signs and treatment recommendations in brittle nails: A review. Dermatol Ther (Heidelb). 2020; 10(1): 15-27. doi: 10.1007/s13555-019-00338-x
Leyden J, Dunlap F, Miller B, Winters P, Lebwohl M, Hecker D, et al. Finasteride in the treatment of men with frontal male pattern hair loss. J Am Acad Dermatol. 1999; 40: 930-937. doi: 10.1016/ s0190-9622(99)70081-2
Kaufman KD, Olsen EA, Whiting D, Savin R, DeVillez R, Berg-feld W, et al. Finasteride in the treatment of men with androgenetic alopecia. Finasteride male pattern hair loss study group. J Am Acad Dermatol. 1998; 39: 578-589. doi: 10.1016/s0190-9622(98)70007-6
Dickinson A., Shao A., Boyon N. Use of dietary supplements by cardiologists, dermatologists and orthopedists: Report of a sur-vey. J Nutr. 2011; 10: 20. doi: 10.1186/1475-2891-10-20
Skeie G, Braaten T, Hjartåker A. Use of dietary supplements in the European Prospective Investigation into Cancer and Nutri-tion calibration study. Eur J Clin Nutri. 2009; 63: S226-S238. doi: 10.1038/ejcn.2009.83
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