Reviewed: 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 [published online April 23, 2014]. Evid Based Complement Alternat Med. doi: 10.1155/2014/549721.
Androgenetic alopecia (AGA) is a form of hair loss common in older men that is linked to both genetic factors and effects of androgenic hormones. Standard drug therapies used to treat AGA often produce adverse side effects. This has led researchers to explore alternative treatments, such as natural products that block the action of androgenic hormones or the enzyme 5α-reductase, which is involved in the conversion of testosterone to dihydrotestosterone. Studies have suggested that pumpkin (Cucurbita pepo, Curcurbitaceae) seed oil (PSO) may exhibit some of these effects, but it had not been investigated as a treatment for AGA. The aim of this randomized, placebo-controlled, double-blind study was to evaluate the efficacy and safety of PSO for male patients with mild-to-moderate AGA.
This 24-week study was conducted in Busan, South Korea. Patients had moderate hair loss that was classified as Norwood-Hamilton type II, III, III vertex, IV, or V. A total of 76 adult males (aged 20 to 65 years) participated in the study. Criteria for inclusion were mild-to-moderate AGA, no use of any hair-loss treatment for three months prior to the study, liver enzymes aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels less than 60 mg/dl, and creatinine levels below 1.5 mg/dl.
Patients were divided randomly into either the intervention group (n=37) — which consumed two capsules of 100 mg PSO (Octa Sabal Plus®; Saerona Co., Ltd.; Daegu, South Korea) twice per day, 30 minutes before breakfast and dinner — or the control group (n=39), which received the same number of identical placebo capsules. No information about the supplement or placebo was provided.* Safety and compliance were evaluated by reports of adverse side effects and pill counts, respectively, at each clinic visit after one, four, and 12 weeks of treatment. At baseline and at 24 weeks, blood samples were obtained after 12 hours of fasting. Fasting blood glucose, serum AST, serum ALT, γ-glutamyltransferase (GGT), creatinine, and testosterone levels were determined from the blood samples.
Patients rated their observations using a visual analog scale (VAS; from worst to best: 0-10) for hair growth improvement and satisfaction with the treatment. Pictures of the patients’ scalps (vertex and superior frontal scalp) were taken at baseline and 24 weeks. Blinded investigators assessed these photos and rated changes in scalp appearance from baseline to 12 and 24 weeks using a seven-point rating scale (from worst to best: -3 to +3). Hair counts and hair diameters were measured at baseline, 12 weeks, and 24 weeks by phototrichography (a technique in which a close-up image of a well-defined scalp area is taken and analyzed using special software). The hair changes were evaluated by a technician who established the most severe site of baldness as the region for all subsequent measurements.
There were no significant differences between the intervention and placebo groups’ demographic data, body measurements, or clinical characteristics at baseline. At 12 weeks, there were no significant differences between the two groups for self-rated improvement (P=0.514) or self-rated satisfaction (P=0.214). However, self-rated improvement was significantly higher (P=0.013) in the intervention group (3.4 ± 2.9) compared to the placebo group (2.1 ± 2.0) after 24 weeks. Self-rated satisfaction also was significantly higher (P=0.003) in the PSO group (3.5 ± 2.9) in comparison to the placebo treatment (2.3 ± 2.0) at 24 weeks.
Blinded investigators determined that treatment with PSO significantly increased hair growth compared to the placebo group at both 12 and 24 weeks (P<0.001). Based on measurements with phototrichography, it also was found that at 12 and 24 weeks the hair count percentages (change from baseline) were significantly higher (P<0.001) in the intervention group (30% and 40% after 12 and 24 weeks, respectively) compared to the placebo group (5% and 10%). Conversely, there were no significant differences found for change in hair thickness at 12 and 24 weeks (P=0.991). Most of the patients did not report any adverse side effects, although one patient from each group complained of a whole-body itching sensation. One patient in the intervention group also reported mild abdominal discomfort. No major toxicity issues were observed in this study; liver enzymes, creatinine, testosterone, blood pressure, and glucose were not significantly altered.
The authors conclude that PSO may be a promising treatment for AGA but also mention that the mechanisms of action of PSO were not investigated. Although this was the first time a clinical study evaluated the efficacy and safety of PSO for the treatment of AGA, a previous 12-month randomized, double-blind, placebo-controlled study demonstrated that a similar dose of PSO was a safe and effective treatment for patients with benign prostatic hyperplasia (BPH).1 The present study not only confirms the safety of PSO, but also suggests that the mechanistic effects of PSO may involve inhibition of 5α-reductase, which could explain the effects associated with the treatment of BPH and AGA. Future studies should evaluate the potential mechanistic effects of PSO and confirm the efficacy of this treatment for AGA.
—Laura M. Bystrom, PhD
*Editor’s note: Unfortunately, as is too often the case with pharmacological and clinical trial publications on botanical extracts and related phytomedicinal preparations, the researchers did not provide a description of the tested material, which makes it difficult to assess the results. The CONSORT document on reporting of botanical clinical trials calls for adequate descriptions of such chemically complex preparations.2
- 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.
- Barnes J, Bombardier C, Boon H, Gagnier JJ, Moher D, Rochon P. Improving the quality of reporting randomized controlled trials evaluating herbal interventions: implementing the CONSORT Statement. HerbalGram. 2006;71:50-56.