A large network meta-analysis ranks popular supplements for hair loss and shows who benefits most, but why pills alone won’t replace proven alopecia treatments.
Study: Effects of dietary supplements on androgenetic alopecia: A systematic review and network meta-analysis. Image Credit: AYO Production / Shutterstock.com
A recent study published in Frontiers in Nutrition uses a network meta-analysis approach to compare the effectiveness and safety of multiple dietary supplements for hair loss.
Hair loss: Prevalence and pathology
Androgenetic alopecia (AGA) is the most common progressive hair disorder worldwide, characterized by follicular miniaturization and transformation of terminal hairs into vellus hairs. AGA can lead to progressive scalp thinning or hair loss, which can significantly impact the patient’s appearance and quality of life.
The prevalence of AGA increases with age, with about 50 % of men over 50 years of age affected by the condition, whereas women often experience diffuse thinning with increased incidence after menopause. Pathologically, AGA results from genetic susceptibility and disturbances in androgen metabolism.
In susceptible individuals, dihydrotestosterone (DHT), a testosterone metabolite produced by 5α-reductase, binds to follicular androgen receptors. This shortens the anagen phase, prolongs telogens, and progressively miniaturizes hair follicles.
Study rationale and data sources
To date, several treatments for AGA have been approved by the United States Food and Drug Administration (FDA), including finasteride, a 5α-reductase inhibitor, and minoxidil, a vasodilator and follicle activator. Both treatments have considerable efficacy and acceptable safety profiles; however, inter-individual variability and tolerability issues necessitate the development of adjunctive interventions with improved tolerability.
For the current meta-analysis, the authors reviewed relevant randomized controlled trials (RCTs) evaluating dietary supplements for the treatment of androgenetic alopecia (AGA) from major medical databases, including PubMed, Cochrane Library, Embase, and Web of Science. A total of 1,105 potentially relevant studies were initially identified, of which 19 RCTs met all eligibility criteria.
Network meta-analysis (NMA) enables comparison of multiple interventions within a single framework. Although previous NMAs report that dietary supplements improve hair health in AGA patients, no NMA has specifically evaluated dietary supplements for AGA treatment. Thus, the current review is the first to systematically evaluate the efficacy and safety of dietary supplements for AGA.
The researchers analyzed 16 interventions across 19 RCTs involving 1,658 patients. These studies evaluated hair density, terminal hair density, and blinded physician assessments, with surface under the cumulative ranking (SUCRA) curves used to guide clinical decisions.
Dietary AGA treatment strategies
Dietary supplements have emerged as promising AGA interventions due to their natural origins and multi-target mechanisms. Saw palmetto extract (ESR) and pumpkin seed oil (PSO) inhibit 5α-reductase, whereas tocotrienols provide antioxidant protection, and omega fatty acids reduce inflammation. However, small sample sizes and a lack of direct comparative studies limit conclusions about their relative efficacy.
Interventions including plant extracts (Nutrafol), apple extract (AMSbzs and AMS), tocotrienol, PSO, and compound extract of Cistanche and Laminaria (MK-R7) significantly outperformed placebo for hair density, with Nutrafol ranking highest at a SUCRA score of 81.1 %.
ALRV5XR, Nutrafol, and probiotics significantly improved terminal hair density as compared to placebo, with ALRV5XR ranking first at 99 %. Subgroup analyses suggested that improvements in terminal hair density may be more pronounced when supplements are combined with topical agents, although the evidence remains limited.
In blinded physician evaluations, PSO and capsaicin-isoflavones (CI) significantly outperformed controls, with PSO ranking highest at 73.1 % after finasteride.
For the terminal-to-vellus hair ratio, no significant differences were observed between dietary supplements and controls; however, ALRV5XR, probiotics, and Omega 3&6 ranked highest. Terminal-to-vellus hair ratio did not show statistically significant differences versus placebo or conventional treatment, though ALRV5XR, probiotics, and Omega 3&6 ranked highest in the SUCRA, suggesting the need for larger studies to validate these findings.
Subgroup analyses examined intervention modality and population characteristics, including sex, duration, and single versus multi-component, none of which correlated with any significant differences in efficacy. However, several moderating effects emerged; for example, combining supplements with topical therapy was associated with greater observed improvements in terminal hair density, suggesting a potential systemic-local synergy.
Supplements improved blinded physician outcomes as compared to placebo but not relative to finasteride, indicating suitability as adjuncts rather than replacements. Notably, women experienced statistically significant benefits in terminal hair density with supplements, particularly menopausal women, whereas the larger effect sizes observed among male participants did not reach significance due to smaller sample sizes.
Conclusions
Existing evidence confirms the benefits of various supplements, including Nutrafol for hair density, ALRV5XR for terminal hair density, and PSO for visible improvements. This effectiveness is likely due to several mechanisms, including androgen modulation, reduced oxidative stress, and improved microcirculation.
Supplements outperformed placebo but not prescription drugs, suggesting their potential utility as adjunctive therapy. Postmenopausal women benefited most from supplement treatment, with available evidence for men considered insufficient. Compared with single therapy, combination therapy with supplements and topical agents demonstrates the greatest observed efficacy.
However, the certainty of evidence was rated as low for terminal hair density and blinded physician assessments, reflecting small sample sizes, heterogeneity, and reliance on indirect comparisons.
Although supplements were mostly well tolerated, most studies were short-term, and variability in formulation, dosing, duration, and topical co-interventions limits the ability to make direct clinical recommendations. In the future, larger and longer randomized trials with stratified analyses by sex, age, and special populations are needed to validate efficacy and long-term safety for standardized clinical use.
