Pumpkin Seed Oil for Hair Growth: A Scientific Review

Did you know that pumpkin seed oil may be able to improve hair count and hair thickness in men with hair loss problems? This comes from the results of a 24-week research trial, which I’ll discuss in-depth below. Recent research also suggests it might be effective against female hair loss.

This article will answer the following questions:

• What is pumpkin seed oil, and what does it do?
• What does science have to say about it?
• Are there side effects?
• How do you use it?
• What’s the bottom line?

But first, let’s take a quick look at what causes pattern hair loss (Androgenetic Alopecia or AGA) in the first place.

An Introduction to Pattern Hair Loss

AGA is estimated to affect about 50 million men in the US (1). It generally begins with hair loss at the temples, continues around the crown, and can eventually lead to total baldness.

AGA has a genetic predisposition (2). This means that the more relatives you have with it, the more likely you are to develop AGA yourself. The principal androgen believed to be associated with it is dihydrotestosterone (DHT) (3).

When DHT binds to androgen receptors on the hair follicles, it shortens their hair growth cycle and delays the growth of the new hairs (4). Over time, the follicles completely stop growing new hair.

Treatment Options

The pharmaceutical treatment options for AGA are minoxidil and finasteride.

Minoxidil, commercially known as Rogaine, is a topical treatment that stimulates hair follicles.

Finasteride, brand name Propecia, is a pill that works by binding to the enzyme 5-alpha-reductase. This is the enzyme that would otherwise convert free testosterone to DHT (5). The result is that the levels of DHT in the body plummet. Propecia can halt hair loss for up to 80% of men, but it is relatively ineffective at regrowing many new hairs.

Both of these pharmaceutical options can be costly, and they also have potential adverse side effects.

An inexpensive, natural substance like pumpkin seed would certainly appeal to man men with AGA if it worked.

What Is Pumpkin Seed Oil?

Pumpkin seed (Cucurbita pepo) oil is obtained by expeller-pressing toasted, hulled pumpkin seeds. It is a rich source of antioxidants, essential fatty acids, minerals, and more (6).

Chemically, the oil consists mainly of saturated and unsaturated fatty acids. These include myristic acid, palmitic acid, oleic acid, linoleic acid, and linolenic acid. It also contains beta-sitosterol, the importance of which we will discuss later.

Aside from being a delicious edible plant, pumpkin is also known to have substantial anti-inflammatory and other medicinal properties (7, 8, 9).  People use it to treat all sorts of conditions, from prostate problems to high cholesterol and more (10, 11, 12).

Health Benefits

There are many purported health benefits to pumpkin seed oil, and most are unrelated to hair loss. The following is a summary of the main ones:

Mineral Support

Pumpkins, like all plants that have a close relationship to the soil, are an excellent source of mineral nutrients. Pumpkin seeds, extracts, and oil are all good sources of the minerals phosphorus, magnesium (learn more about magnesium oil), manganese, and copper. They are also excellent sources of zinc and iron.

Antioxidant Support

Pumpkin seeds have a broad diversity of antioxidants. For example, they contain a wide variety of forms of Vitamin E, two of which have only recently been discovered (13).

They also contain mineral antioxidants, phenolic antioxidants, and lignans. This diverse mixture of antioxidants imbues pumpkin seeds with antioxidant properties that are not widely found in other foods.

Anti-inflammatory

Fatty acids isolated from pumpkin seed oil have been used in medicine for their anti-inflammatory properties. We mentioned that the most important of these are linoleic acid, followed by oleic, palmitic, and stearic acid (14).

The people of Central America and India rub the oil extracted from the seeds of pumpkin on herpes sores, venereal sores, acne vulgaris, and stubborn leg ulcers that refuse to heal. Pumpkin leaves are also applied as a poultice on sprains and pulled ligaments.

Antimicrobial

Pumpkin seeds have antibacterial, antifungal, and antiviral properties as a result of their unique proteins (15).

Benign Prostatic Hyperplasia (BPH)

Pumpkin seed oil has been used to treat BPH successfully, based on its phytosterol, lignan, and zinc content. Interestingly, this is what finasteride was originally intended to treat (16, 17). We will return to the significance of this shortly.

Pumpkin Seed Oil & Hair Loss In Men

In 2014, Evidence-Based Complementary and Alternative Medicine published the results of a clinical research study that investigated Pumpkin Seed Oil (PSO) as a treatment for AGA (18).

This was the first randomized, double-blind, placebo-controlled trial of its kind. The 24-week trial recruited 76 male subjects with mild to moderate AGA. Half took a daily supplement (which included PSO) in the form of a 400 mg capsule. The other half received a placebo capsule.

IMPORTANT! The supplement given to participants was Octa-Sabal Plus. This does contain pumpkin seed powder but also additional ingredients. These include Octacosanol (from vegetable powder), Gamma-linolenic acid (from evening primrose), and Lycopene (from tomato powder). It is not possible to say whether the PSO was solely responsible for the results, or if the other ingredients also played a role (which is quite likely).

The researchers used phototrichography to analyze hair changes, including hair counts and diameters. They did this at the start of the trial to establish a baseline, after 12 weeks of treatment, and again after 24 weeks of treatment.

You can see the results in the two graphs below. They show that the PSO treatment group had significant increases in hair count over the placebo group. The differences in hair thickness were negligible.

From these results, the researchers concluded that taking a PSO supplement for 24 weeks positively affects hair growth in patients with mild to moderate AGA. They believed this could be due to the possible effects of 5-reductase inhibition (which we discuss below).

Against Female Hair Loss

In 2021, researchers from Cairo University recruited 60 women with pattern hair loss (19). Though clinically different from men, women’s hair loss responds to many of the same treatments. The results of this research are therefore also of interest to men.

The researchers randomly assigned each woman to one of two treatment groups:

• topical pumpkin seed oil once daily
• minoxidil foam 5% once daily

Treatment lasted 3 months for both groups. The researchers looked at the following efficacy parameters:

• hair shaft diversity. One of the hallmarks of pattern hair loss is unequal hair shaft size. This is because, at any given time, hairs on the scalp will have miniaturized to various degrees. A healthy head of hair, on the other hand, has hair shafts of relatively equal diameter. This means that an effective hair loss treatment should decrease hair shaft diversity in balding women (and men).
• the number of vellus (immature) hairs. These are soft, baby-like, and cannot provide sufficient coverage. A feature of pattern hair loss is the gradual conversion of terminal to vellus hairs.
• the number of terminal (mature) hairs. Unlike vellus hairs, these terminal hairs can grow long, thick, and dark. A successful hair loss treatment should increase their numbers.

After three months, both the pumpkin seed oil and minoxidil gave a statistically significant improvement in all three parameters. The hair shaft diversity went down in both groups, as did the mean number of vellus hairs. The number of terminal hairs, on the other hand, increased for both groups. On this last metric, the minoxidil-treated women had a clear advantage (approximately double the regrowth).

These results suggest that pumpkin seed oil is effective against female pattern hair loss, though perhaps not quite as much as minoxidil.

Pumpkin Seed Oil  & DHT

Taken together, the evidence above suggests that PSO has some effect against pattern hair loss in both men and women.

Some researchers have speculated that this might be due, at least in part, to the oil’s anti-androgenic properties, and particularly its ability to inhibit the synthesis of DHT. Let’s look at the evidence for this.

Pumpkin Seed Oil Relieves Prostate Enlargement

Benign prostate enlargement (BHP) is an ailment that affects many men as they age (20). Though benign (non-cancerous) in nature, it has symptoms like increased frequency of urination and difficulty urinating that may lower quality of life. Interestingly, it is linked to DHT, and medications that relieve BHP also tend to be effective against hair loss. It is no coincidence that finasteride was first approved for the treatment of BHP and only subsequently for hair loss.

In 2009, a team of Korean researchers reported that pumpkin seed oil (and saw palmetto oil) was effective in relieving the symptoms of BHP in men (21). Other researchers have found that pumpkin seed oil can block prostate growth in rodents (22, 23). Taken together, these results strongly suggest pumpkin seed oil has some anti-DHT properties.

Pumpkin Seed Oil Inhibits DHT In Vitro

Other scientists have studied the direct effect of pumpkin seed oil and its active compounds in inhibiting the synthesis of DHT in vitro (in a lab). The results confirm that it is a potent inhibitor of DHT (24). Earlier research has found that beta-sitosterol, one of the main compounds of pumpkin seed oil, inhibits DHT on its own (25, 26).

It Increases Hair Growth Suppressed by Testosterone

In rodents, topical administration of testosterone inhibits hair growth.  A 2019 study from Iran found that topical pumpkin seed oil can reverse this testosterone-induced hair growth retardation (27). Again, this is suggestive of a potent anti-androgenic effect.

Are There Side Effects?

According to the University of Michigan Health System, pumpkin seed oil has no reported side effects.

However, it has been speculated that it might have a diuretic effect (28). For those of you taking lithium, taking a pumpkin seed oil-containing supplement might decrease your body’s ability to metabolize the lithium. This could increase its retention in the body and result in serious side effects.

It is important to note that any natural remedy can cause an allergic reaction in some people, and this holds true for pumpkin and its many derivatives (i.e. oils, extract, etc.) as well.

Signs of an allergic reaction may include breathing problems, tightness in the chest or throat, chest pain, hives or rash, and itchy or swollen skin. You should treat any of these reactions as a potential medical emergency.

Women who are pregnant or nursing should not take any supplements without consulting their doctor.

How Do You Use Pumpkin Seed Oil On Your Hair?

There are two ways to incorporate pumpkin seed oil into your hair care routine: topically and orally.

Topical Pumpkin Seed Oil

For maintaining a healthy scalp, pumpkin seed oil should be massaged into the scalp with some type of carrier oil such as olive oil and then left in overnight. You might want to warm it gently before application, or you can use it at room temperature.

You should repeat this at least twice a week for a minimum of two months before expecting to see results.

Supplementation

For treatment of AGA, pumpkin seed oil is ingested orally as a supplement. Pumpkin Seed oil (Cucurbita pepo) supplements are widely available online and at drug stores, grocery stores, and nutrition specialty stores. Manufacturers sell them in the form of capsules or soft gel caps. Note these supplements are not regulated by the FDA. As a result, there can be large differences in quality and potency between various brands. Make sure to read reviews from other customers first, and always source your supplements from a reputable manufacturer.

Dosages range from 500 to 1000 mg. Prices typically range from 15 cents to 35 cents per unit, depending on the dosage, brand, and quantity purchased.

Individuals deciding which supplement to buy should look for those containing pure, unrefined, organic pumpkin seed oil that has been expeller-pressed. A recommended dosage for the particular treatment of AGA has not been established, but 500mg seems like a reasonable starting point.

Combining With Other Treatments

While you can choose to apply PSO to the scalp or take it as a daily supplement, there are treatments you can combine it with to boost its effectiveness.

Microneedling

There are plenty of oils you can combine with microneedling to improve results, but pumpkin seed oil is one of the better options.

Microneedling is a procedure that involves the use of tiny needles (29). They create micro-wounds that, when they heal, help to promote collagen production and the proliferation of skin cells (30).

You can use a dermaroller or a dermastamp, though a dermastamp is the more popular recommendation.

Just apply the dermastamp to the areas of hair loss, and press down until the needles penetrate the scalp. Do this horizontally, vertically, and diagonally.

Once weekly microneedling sessions are sufficient to see results in most cases. On the days that you microneedle you can skip the pumpkin seed oil.

Scalp Massage and Exercises

The dermaroller and dermastamp are great tools to use to increase blood circulation to the scalp. But you can also do so with your hands.

In 2016, a study suggested that 24 weeks of standardized scalp massage can increase hair thickness (31). This is the case not only with balding men but also for those with healthy hair. The results appear to be dose-dependent; the more you massage, the better results you can expect (32).

How to Perform Scalp Massages

Using just your fingertips (and maybe some PSO), place your thumbs, index, and middle fingers on either side of your head (just above the ears). Place varying levels of pressure throughout the massage, and begin to use circular motions.

You will start at the sides and then move up to the crown, to the hairline and temples, and finally to the base of the scalp.

You can also trace back at any point during the massage, and even focus more exclusively on thinning areas.

This should take 10 – 15 minutes per day.

How to Perform Scalp Exercises

To further increase blood circulation, you can use your facial muscles to stretch and gently pull the skin of the scalp. Here is a quick rundown of how:

1. Lift your eyebrows as high as possible, and hold for 2 minutes. Return to resting position.
2. Furrow your eyebrows as deep as possible, and hold for 2 minutes. Return to resting position.
3. Lift your eyebrows as high as possible, and hold for 2 minutes. Then furrow your eyebrows as deep as possible, and hold for 2 minutes. Finally, return to the resting position.

You can also use your fingertips, and gently stretch the skin by pulling and pushing your fingers together.

What’s the Bottom Line?

In recent years, pumpkin seed oil (PSO) has emerged as a superfood packed with protein, micronutrients, and healthy fats. Alongside this increased public interest in PSO, there is promising scientific evidence to support its use as a treatment for mild to moderate AGA.

Over the years, researchers have compiled evidence that PSO is involved in the inhibition of DHT and can be effective against both male and female hair loss.

While you can always apply it topically, it will generally be far easier and more practical to supplement. Since PSO products are not regulated by the FDA, be sure to do your due diligence when selecting a brand. Allow a minimum of 3 months’ use before deciding if PSO is right for you.