Do Pepitas Block DHT? Understanding the Science for Hair Health

December 10, 2025 •

3 min read

A significant portion of hair loss is linked to the hormone dihydrotestosterone (DHT), which can shrink hair follicles in susceptible individuals. Recent research suggests that specific compounds within pepitas, or pumpkin seeds, may potentially block DHT, offering a natural approach for hair health.

Quick Summary

Pepitas contain phytosterols that may inhibit the enzyme responsible for converting testosterone to DHT, offering a natural approach to mitigate androgenetic hair loss.

Key Points

Inhibits 5-AR: Pumpkin seed oil, derived from pepitas, contains phytosterols that may block the 5-alpha reductase enzyme, which converts testosterone into DHT.
Supported by a Clinical Study: A 2014 randomized trial showed men taking pumpkin seed oil supplements experienced a 40% increase in hair count over 24 weeks.
Oil is More Concentrated: The DHT-blocking effect is most evident in cold-pressed pumpkin seed oil used in studies, not necessarily whole seeds alone.
Provides Broader Nutrition: Pepitas are rich in beneficial nutrients like zinc, omega-3s, and antioxidants that support overall hair and scalp health.
Mild, Natural Alternative: Offers a promising, milder alternative to pharmaceutical DHT blockers like finasteride, with fewer reported side effects.
Not a Cure-All: While potentially effective, pepitas are not a guaranteed cure for hair loss and work best as part of a comprehensive strategy.

The Role of DHT in Hair Loss

Dihydrotestosterone, or DHT, is an androgen hormone that is a significant driver of androgenetic alopecia (AGA), the most common form of hair loss in men and women. In individuals with a genetic sensitivity, DHT binds to receptors in hair follicles, initiating a process called miniaturization. This causes the follicles to progressively shrink, shortening the hair's growth cycle and leading to thinner, finer, and eventually non-existent hair. To combat this, many individuals seek ways to naturally block DHT production.

The Science Behind How Pepitas Might Block DHT

The 5-Alpha Reductase Enzyme

DHT is produced from testosterone by the enzyme 5-alpha reductase (5-AR). Inhibiting this enzyme is the primary mechanism targeted by most DHT-blocking treatments. Pumpkin seeds, or pepitas, contain compounds that may interfere with this conversion.

Phytosterols: The Active Compounds

Pepitas are rich in phytosterols, plant-based compounds similar to cholesterol. Key phytosterols in pepitas, like beta-sitosterol and delta-7-stearine, may inhibit the 5-AR enzyme, reducing DHT conversion and protecting hair follicles from miniaturization.

Clinical Evidence and Research on Pumpkin Seed Oil

Research on pepitas and DHT largely focuses on cold-pressed pumpkin seed oil (PSO), which has a high concentration of active phytosterols. A notable 2014 randomized, double-blind, placebo-controlled trial involving 76 men with AGA showed promising results. Participants taking 400 mg of PSO daily for 24 weeks experienced a 40% increase in hair count, compared to a 10% increase in the placebo group. They also reported overall improvements in hair growth. While encouraging, more extensive studies are needed to confirm these findings.

Pepitas vs. Pumpkin Seed Oil for DHT Blocking

For DHT-blocking effects, concentrated pumpkin seed oil supplements are considered more effective than consuming whole pepitas due to the higher concentration of phytosterols used in studies. Oral supplementation is typically favored over topical application for DHT inhibition, although applying the oil to the scalp can support overall hair and scalp health.

Comparison: Natural DHT Blockers vs. Pharmaceuticals


Feature	Pumpkin Seed Oil (from Pepitas)	Prescription Finasteride
Mechanism	Indirectly inhibits 5-AR via phytosterols.	Directly inhibits 5-AR enzyme activity.
Efficacy	Modest effects shown in limited clinical trials.	Robustly proven effectiveness in slowing hair loss.
Side Effects	Generally mild, with few reported adverse effects.	Potential for sexual side effects, mood changes, and hormonal imbalance.
Consistency	Requires consistent use over several months for results.	Requires continuous use to maintain benefits.
Safety Profile	High safety profile; side effects are rare.	Well-established safety, but potential side effects must be considered.

Beyond DHT: The Broader Nutritional Benefits of Pepitas

Pepitas also offer significant nutritional value for hair health:

Zinc: Essential for hair growth and repair, with deficiency linked to thinning. Pepitas are a good source.
Essential Fatty Acids: Omega-3 and omega-6 help nourish the scalp, improve circulation, and reduce inflammation.
Antioxidants: Vitamin E protects hair follicles from damage.
Iron and Magnesium: Support hair strength and prevent breakage.

How to Incorporate Pepitas and Oil for Hair Health

To potentially benefit from pepitas for hair health:

Eat Whole Pepitas: Add raw or roasted pepitas to your diet for nutrients.
Take Pumpkin Seed Oil Supplements: Oral capsules offer a concentrated dose of phytosterols, considered more effective for DHT blocking.
Use Pumpkin Seed Oil Topically: Massage into the scalp to improve circulation and nourish follicles, though oral intake is better for DHT inhibition.

Limitations and Considerations

While the research on pumpkin seed oil is promising, it's important to have realistic expectations. The 2014 study is a good starting point but not a large-scale, definitive trial. Pepitas and their oil are natural options, and their effects are often milder and slower than prescription medications. Consult a healthcare professional to determine the best approach for your specific hair loss concerns.

Conclusion: The Final Verdict on Pepitas and DHT

Evidence suggests that compounds in pepitas, particularly the phytosterols in cold-pressed pumpkin seed oil, have potential to block DHT. A 2014 clinical trial showed improved hair count in men with AGA using PSO. The effect is generally milder than pharmaceutical blockers like finasteride and requires consistent oral intake of the oil. Incorporating pepitas or their oil can be a valuable natural strategy for supporting hair health, especially when combined with a balanced diet.

Explore more research on the effects of pumpkin seed oil on hair growth.

Frequently Asked Questions

While whole pepitas contain the active phytosterols, the concentration may be too low for a significant effect. Most research showing a DHT-blocking effect has used concentrated pumpkin seed oil capsules.

No, the DHT-blocking effect of pumpkin seed oil is generally considered milder than prescription finasteride. Finasteride is a more potent and robustly proven inhibitor of the 5-AR enzyme.

Based on the 2014 clinical trial, participants saw a significant increase in hair count after 24 weeks of consistent, daily oral supplementation. Results are not immediate and require patience.

Topical application of pumpkin seed oil can benefit overall scalp health and circulation. However, for significant DHT inhibition, oral consumption is considered more effective, as demonstrated in clinical studies.

Pumpkin seed oil has a high safety profile, and side effects are rare and generally mild, unlike some pharmaceutical options. Some people may experience mild stomach upset.

Beyond their DHT-blocking potential, pepitas are rich in zinc, iron, magnesium, omega-3 and omega-6 fatty acids, and vitamin E, all of which support healthy hair and scalp.

The mechanism of blocking DHT is relevant to androgenetic alopecia in both men and women. Studies specifically on women are more limited, but the logic and nutritional benefits still apply, though results may vary.