Pumpkin Seed Oil: Small Trials, One Big One, and a Catch

The Oasis Health Journal · Submitted July 23, 2026 · 5:24 PM ET

Pumpkin seed oil is what you get when you press the part of the pumpkin most people scrape into the trash. It is green, it tastes like toast, and it has been through more human trials than you would expect for something that starts as a jack-o-lantern byproduct. The research is small and uneven. It is also more interesting than nothing.

Where the interest started: hair

The study people cite most is from Korea. Researchers gave 76 men with mild to moderate pattern hair loss either 400 mg of pumpkin seed oil a day or a placebo, for 24 weeks. They counted hairs. The oil group ended with about 40% more hair on average. The placebo group ended with about 10% more. That is a real gap, in a real randomized trial, and it is also 76 men for 24 weeks, which is a study, not a settlement. Hair supplements are a crowded shelf, and most of them do not have even this much behind them.

Worth noting what the study did not do. It did not regrow a chrome dome. It did not compare against the standard options. It counted hairs in men who still had some. People taking it reported being more satisfied with their hair. That is the finding. It is fine to want more.

The other half of the file: the bathroom

Most pumpkin seed research is not about hair at all. It is about men getting up at night. In one 12-month randomized trial of 1,431 older men with lower urinary tract symptoms, whole pumpkin seed edged out placebo. About 58% of the seed group met the improvement bar, versus about 47% on placebo. The plot twist: a concentrated pumpkin seed extract in the same study did no better than placebo. The whole seed did something the extract did not, which is not how supplements are supposed to work, and the authors said as much. They asked for a confirmatory study before anyone gets excited.

There is also a smaller, unblinded Japanese study of 45 people taking pumpkin seed oil for 12 weeks. Their overactive bladder scores dropped. No placebo group, so read it lightly. It rhymes with the bigger trial without proving anything. Men who want to read about this category usually end up on prostate shelves, where pumpkin seed tends to ride along with other botanicals.

It is not only a men's aisle

One observational study followed 117 women with overactive bladder using a blend that included pumpkin seed oil, along with sumac and hops. Leakage episodes and pad use went down over 12 weeks. The catch is large: it was not blinded, it was not placebo-controlled, it was industry-run, and it was a blend, so nobody can hand the credit to the pumpkin alone. It belongs in the file as a footnote, not a headline.

What pumpkin seed oil is, mechanically

The oil is mostly fatty acids, plus phytosterols, plus a little vitamin E and zinc. Researchers think the phytosterols are the interesting part, since sterols sit in the same neighborhood as the other plant compounds studied for prostate comfort. Nobody has nailed the exact mechanism. Cold-pressed pumpkin seed products keep more of the fragile compounds than heat-pressed ones, which is the one sourcing detail worth caring about.

The honest summary

Pumpkin seed oil has a handful of small human trials, one of which is genuinely large, pointing in a consistent direction for hair and for urinary comfort. None of it is a slam dunk. The extract-versus-whole-seed surprise is a reminder that form matters and that the science is not finished. It is a reasonable thing to try and a bad thing to bet the house on.

This article is for education, not medical advice. Talk with your clinician before starting a new supplement, especially if you are pregnant, nursing, or taking medication.

Sources

1. Cho YH, Lee SY, Jeong DW, Choi EJ, Kim YJ, Lee JG, Yi YH, Cha HS. Effect of pumpkin seed oil on hair growth in men with androgenetic alopecia: a randomized, double-blind, placebo-controlled trial. Evidence-Based Complementary and Alternative Medicine, 2014;2014:549721. PubMed
2. Vahlensieck W, Theurer C, Pfitzer E, Patz B, Banik N, Engelmann U. Effects of pumpkin seed in men with lower urinary tract symptoms due to benign prostatic hyperplasia in the one-year, randomized, placebo-controlled GRANU study. Urologia Internationalis, 2015;94(3):286-295. PubMed
3. Nishimura M, Ohkawara T, Sato H, Takeda H, Nishihira J. Pumpkin seed oil extracted from Cucurbita maxima improves urinary disorder in human overactive bladder. Journal of Traditional and Complementary Medicine, 2014;4(1):72-74. PubMed
4. Gauruder-Burmester A, Heim S, Patz B, Seibt S. Cucurbita pepo-Rhus aromatica-Humulus lupulus combination reduces overactive bladder symptoms in women: a noninterventional study. Planta Medica, 2019;85(13):1044-1053. PubMed