Background: Hair loss, with its wide range of causes and types, has been a major concern for a large population. Baldness or hair thinning has caused a lack of self-perceived confidence and deteriorating quality of life. Biotin, vitamin B12, and B complex multivitamins are the most commonly used supplements, amongst many. Despite the rising use, and the apparent safety these supplements seem to entail, the effectiveness of these supplements is still questionable.
Objective: This systematic review and meta-analysis aims to evaluate the effect of nutritional supplements on hair loss.
Methods: Cochrane Library, Scopus and Pubmed were search till March 2023 from their inception. Relevant randomized control trials were identified using keywords according to the preferred reporting items for systematic reviews and meta-analysis (PRISMA guidelines). The reference lists of relevant articles were manually searched to identify additional studies. Studies were included if they met the following criteria: (1) randomized controlled trial design, (2) published in English, (3) evaluating the efficacy of nutraceutical supplements on alopecia, (4) providing quantitative data on hair growth parameters, (5) include a control group and (6) conducted in human participants. Data were analyzed using Review Manager (RevMan) version 5.4 software. Forest plots were used to visualize the results of the meta-analysis, and effect sizes were expressed as odds ratio (OR) or standardized mean differences (SMD) and their respective 95% confidence intervals (CI). A p-value < 0.05 was considered significant. Subgroup analysis was performed too. The outcomes included change in total hair count, change in vellus hair, change in terminal hair, and change in hair thickness with the use of nutritional supplements.
Results: This meta-analysis included 11 RCTs. Nutritional supplements were seen to improve terminal hair length. (SMD=1.37, 95% CI [0.53 to 2.22], Z=3.19, P=0.001). In the subgroup analysis, Viviscal was only seen to have a positive correlation with terminal length. Overall supplements, however, had insignificant effects on total hair count (SMD= 0.17, 95% CI [-0.20 to 0.54], Z=0.89, P=0.37), hair thickness (OR=1.60, 95% CI [0.33, 7.69], Z=0.59, P=0.56), and vellus hair (SMD=0.38, 95% CI [-0.03, 0.78], Z=1.83, P=0.07). Our subgroup analysis, despite the concurrent total results, revealed that Nutrafol improved these variables.
Conclusion: The conducted meta-analysis suggests that nutritional supplements have the potential to improve terminal hair in individuals with alopecia. Despite the need for larger randomized controlled trials, the findings provide important insights for clinicians in the management of alopecia. Further research is needed to standardize supplement dosages and predispose combinations and provide more definitive evidence on the efficacy of nutritional supplements as treatment options for alopecia.
Audience Take Away Notes:
- Overall, nutritional supplements only improve the terminal hair length
- They should not be prescribed without considering the specific need of the patients and the effect of the type of supplement
- There is a stereotype that all nutritional supplements improve hair quality, and thus, it is taken by patients in indefinite quantities. This must change to avoid adverse effects.
- Specific supplements have specific effects on terminal hair length, vellus hair, hair count and thickness
- This meta-analysis highlights the need for larger, carefully-designed randomized controlled trials to confirm the findings obtained in this study and provide more conclusive evidence on the efficacy of nutritional supplements in the prevention and treatment of alopecia