Pumpkin seed oil has been investigated for its potential benefits in supporting hair health, primarily due to its rich content of phytosterols, essential fatty acids, vitamin E, and other bioactive compounds. The most notable scientific evidence comes from a 2014 randomized, double-blind, placebo-controlled trial published in "Evidence-Based Complementary and Alternative Medicine." In this study, 76 men with mild to moderate androgenetic alopecia (male pattern baldness) received either 400 mg of pumpkin seed oil daily or a placebo for 24 weeks. The results showed a statistically significant increase in hair count (about 40% increase) among those taking pumpkin seed oil compared to placebo, with minimal side effects reported.

The hypothesized mechanism involves pumpkin seed oil's inhibition of 5-alpha reductase, an enzyme responsible for converting testosterone to dihydrotestosterone (DHT), a hormone implicated in hair loss. Animal studies and in vitro experiments also support this mechanism, though human data is still limited. While these findings are promising, the overall body of evidence is small, with relatively few human trials and limited data on long-term safety and efficacy. Thus, while there is some scientific rationale and initial clinical support, more robust, larger-scale studies are needed to confirm pumpkin seed oil's effectiveness for hair health.