Pumpkin seed oil has also been proven to inhibit the production of 5-alpha-reductase. Pumpkin seeds contain not one but two DHT blockers. The first is beta-sitosterol, a phytosterol, which is structurally like cholesterol. The other is a steroid, delta-7-sterine. A 2014 Chinese study evaluated the effect of a daily dose of 400mg of pumpkin seed oil on 38 men with AGA. A randomized equal number of men received a placebo. After 24 weeks, scientists discovered a 40% mean increase in hair count in the group receiving the pumpkin seed oil as compared to the placebo group.