Pumpkin seeds, Cucurbita pepo (Cucurbitaceae)
Pumpkin seeds, derived from Cucurbita pepo, are the dry fruits of one of the most widely cultivated cucurbit species. Native to the Americas and belonging to the family Cucurbitaceae, the plant is valued not only for its horticultural varieties but also for its edible seeds, which are nutritionally dense and rich in bioactive compounds. Pumpkin seeds may be consumed whole, hulled, or processed into pumpkin seed oil, a specialty product particularly appreciated in parts of Central Europe.
Morphologically, pumpkin seeds are flattened achenes, oval to elliptical in shape, with a seed coat ranging from beige to olive green, the latter typical of hull-less varieties. The seed coat contains mucilage and phenolic substances that offer protection, while the interior endosperm is rich in oily reserves, including lipids and essential nutrients.
Cucurbita pepo grows well in temperate to warm-temperate climates, preferring well-drained soils with good organic matter content. The plant features sprawling or bush-like stems, broad lobed leaves, and the characteristic yellow cucurbit flowers. Seed yield varies widely depending on cultivar, agronomic practices, and fruit maturity stage.
Phytochemically, pumpkin seeds are renowned for their high content of unsaturated fatty acids, particularly linoleic acid (omega-6) and oleic acid, along with smaller amounts of α-linolenic acid. They are a notable source of phytosterols, which may support cholesterol metabolism, and tocopherols (vitamin E) with antioxidant activity. Additional components include high-quality plant proteins, dietary fibre, magnesium, zinc, phosphorus, and a variety of peptides and secondary metabolites under investigation for specific physiological effects.
Nutritionally, pumpkin seeds are regarded as a functional food due to their combination of healthy lipids, antioxidants, and essential micronutrients. Research suggests potential benefits for male urinary function, cardiovascular well-being, and inflammation modulation, although clinical evidence varies depending on dosage, extract type, and consumption method. Given their high caloric density, moderate portion sizes are recommended.
Culinarily, pumpkin seeds are highly versatile:
– consumed roasted or salted as snacks;
– incorporated into breads, crackers, and baked goods;
– added to muesli, salads, or plant-based dishes;
– used for the production of pumpkin seed oil, known for its deep green colour and intense flavour.
Pumpkin seed oil, rich in unsaturated fatty acids and antioxidant compounds, is best used raw, as it is sensitive to oxidation and unsuitable for high-temperature cooking.
Indicative nutritional values per 100 g (hulled, dried pumpkin seeds)
Average values based on European and international composition tables; they may vary depending on species (Cucurbita pepo, C. maxima, C. moschata), cultivar, and drying method.
| Component | Approximate value per 100 g |
|---|
| Energy | ~ 550–560 kcal |
| Water | ~ 4–6 g |
| Total carbohydrates | ~ 10–11 g |
| — of which sugars | ~ 1.3–1.5 g |
| Dietary fiber | ~ 6–7 g |
| Protein | ~ 29–32 g (high) |
| Total lipids | ~ 49–50 g |
| — of which saturated fatty acids (SFA – saturated fatty acids) | ~ 8–9 g |
| — monounsaturated fatty acids (MUFA – monounsaturated fatty acids) | ~ 15–17 g |
| — polyunsaturated fatty acids (PUFA – polyunsaturated fatty acids) | ~ 22–24 g (mainly linoleic acid) |
| Sodium | ~ 5–15 mg |
| Main minerals | magnesium (≈ 500 mg), phosphorus (≈ 1150 mg), potassium (≈ 800 mg), zinc (≈ 7–8 mg), iron (≈ 7–8 mg), copper |
| Relevant vitamins | B-vitamins (B1, B2, niacin, folates), vitamin E, phytosterols and phenolic compounds |
Note on the lipid profile
Pumpkin seeds contain a high proportion of lipids with a favorable balance of MUFA and PUFA.
Saturated fatty acids SFA are moderately present but lower relative to total lipids when compared with many animal sources.
The predominance of PUFA, especially linoleic acid, enhances the nutritional profile.
Nutritional considerations
Excellent source of plant protein, among the richest in the seed and nut category.
Very rich in magnesium, phosphorus, zinc, and iron, supporting energy metabolism, immune function, and muscle health.
Contain phytosterols and phenolic antioxidants.
Typical serving size: 15–30 g per day, suitable as a snack or added to salads, muesli, or baked goods.
Production process
Pumpkin seeds are obtained as a by-product of pumpkin processing. After the pumpkins are cut, the seeds are separated from the pulp, usually by mechanical systems combined with water washing to remove stringy tissue and debris. The clean seeds are then sorted to eliminate damaged seeds and foreign material.
For whole seeds intended for direct consumption, the cleaned seeds are dried with controlled warm air until they reach a safe moisture level for storage. Depending on the product, they may be marketed raw or roasted, with or without shell, plain or salted/flavoured.
For oil production, hulled pumpkin seeds are milled and subjected to mechanical pressing to obtain virgin pumpkin seed oil, or to solvent extraction in more industrial settings, followed by refining steps such as degumming, neutralisation, bleaching and deodorisation. Press cakes and extraction meals are often recovered as protein-rich ingredients for feed.
Applications
In human food, pumpkin seeds are used in many ways: eaten as a snack (roasted, salted or unsalted), incorporated into bread, crackers, breakfast cereals, muesli, granola, bars, salads, soups and vegetable dishes, or processed into seed butters/spreads.
Pumpkin seed oil is used as a cold condiment (notably in Central European cuisines) and as an ingredient in dressings, sauces and certain baked goods.
In animal nutrition, seeds and press cakes can be included in some feed formulations to enhance protein and unsaturated fat content.
In cosmetics, pumpkin seed oil appears in body creams, lotions, massage oils and hair products, particularly aimed at dry skin or dry/damaged hair.
Nutrition & health
Pumpkin seeds are a nutrient-dense, energy-dense food.
Per 100 g of hulled, dried seeds (average values from several databases):
The fat fraction is dominated by unsaturated fatty acids (mainly linoleic and oleic acids), with a smaller saturated component. Pumpkin seeds are also good sources of magnesium, zinc, iron, manganese, phosphorus, potassium and copper, and provide B-group vitamins and vitamin E (especially in the oil).
This composition makes pumpkin seeds interesting for:
Supporting protein intake, particularly in plant-oriented diets.
Contributing to magnesium and zinc intake, important for muscle function, nervous system, immune function and metabolic processes.
Enhancing satiety, thanks to the combination of protein, fat and fibre.
At the same time, because of their high caloric density, attention to portion size is essential, especially in weight-control or low-calorie diets.
Portion note
For everyday use as a snack or topping, a practical portion is around 20–30 g of hulled seeds (about 2–3 tablespoons). This provides useful nutrients without an excessive calorie load when integrated into a balanced diet.
Allergens and intolerances
Pumpkin seeds are not among the major mandatory allergens in common regulations (e.g., EU lists), but:
Individual allergies to pumpkin seeds or pumpkin seed oil do exist and can cause cutaneous or gastrointestinal symptoms.
Some people with multiple seed or nut allergies may show cross-reactivity, so caution is advisable case by case.
In composite products (bars, breads, mixed snacks), most allergenic risk typically comes from other ingredients such as gluten-containing cereals, soy, milk or tree nuts. People with known food allergies should always check the full ingredient list and, when in doubt, seek medical advice.
Storage and shelf-life
Because pumpkin seeds are rich in unsaturated fats, they are prone to oxidative rancidity if poorly stored.
Store seeds in a cool, dry place, protected from light and heat.
Use well-closed packs or jars to limit oxygen and moisture uptake.
In warm climates, keeping opened packs in the refrigerator can help preserve quality.
Under suitable conditions, packaged dry seeds generally have a shelf-life of about 9–12 months (or longer, depending on product specifications).
Pumpkin seed oil should be stored in dark, tightly closed bottles, away from heat; once opened, it is best used within a few months to maintain aroma and oxidative quality.
Safety and regulatory aspects
Pumpkin seeds and pumpkin seed oil are traditional food ingredients and must comply with general food legislation concerning:
Limits for contaminants (heavy metals, mycotoxins, pesticide residues).
Microbiological quality and hygienic processing conditions.
Application of HACCP (Hazard Analysis and Critical Control Points) and GMP (Good Manufacturing Practices) along the production chain.
Any nutrition or health claims (e.g. “source of magnesium”, “high in zinc”) must respect the relevant regulations on authorised nutrition and health claims and be justified by actual nutrient content per portion.
Labeling
On food products, pumpkin seeds appear in ingredient lists as, for example:
“pumpkin seeds”, sometimes with additional descriptors such as “roasted”, “salted”, “hulled” or “shelled”.
Retail packaging must provide:
A nutrition declaration (including energy in kJ and kcal per 100 g and, when applicable, per portion).
Clear indication of any allergens present in the finished product.
Details such as origin and processing (e.g. “roasted”, “unsalted”) when required by local rules.
In cosmetics, pumpkin seed oil is usually listed under the INCI name Cucurbita Pepo Seed Oil.
Main INCI functions (cosmetics)
In cosmetic formulations, pumpkin seed oil is mainly used as:
Emollient / skin conditioning agent: helps soften, smooth and nourish the skin, especially in products for dry or mature skin.
Hair conditioning agent: improves hair softness and feel in hair and scalp products, often combined with other plant oils.
Lipid-replenishing component: contributes to the oil phase structure of emulsions, influencing texture, spreadability and after-feel.
Conclusion
Pumpkin seeds are an energy-dense but nutritionally rich food, supplying unsaturated fats, high-quality plant protein, fibre and key minerals such as magnesium and zinc. In moderate portions they can be a valuable addition to an overall balanced diet, especially as a replacement for less nutrient-dense snacks.
Pumpkin seed oil extends their use into both culinary and cosmetic applications. As with all fat-rich ingredients, appropriate portion control, storage conditions and quality assurance along the production chain are essential to fully benefit from their properties without undesirable effects from excess calories or oxidation.
Studies
The fruit flesh is rich in carotenoids, tocopherols, polysaccharides, carbohydrates and minerals which endow pumpkin with medical functions including antidiabetic, antihypertensive, antitumor, antioxidant, immunomodulation, antibacterial, antihypercholesterolemia, intestinal antiparasitia, anti-inflammation and antalgic activities (1).
The seed contains fatty acids (≤64% linoleic acid), specific delta-7-sterols, tocopherols and micronutrients (2).
The oral administration of high doses of pumpkin seeds and pumpkin seed oil reduced prostate weight in experimental animal models of prostate growth (3).
Pumpkin seed oil is considered a preventive agent for various pathologies, particularly prostate diseases. These properties are related to its high content of carotenoids and liposoluble vitamins. In this study the carotenoid (lutein and zeaxanthin), vitamin E (α- and γ-tocopherol) and fatty acid contents (4).
This study validates the hypoglycemic and antidiabetic effect of Cucurbita maxima seed extract and therefore this extract could be further explored for development as a new anti-diabetic agent (5).
Pumpkin seed studies
References_______________________________________________________________________
(1) Caili F, Huan S, Quanhong L A review on pharmacological activities and utilization technologies of pumpkin. Plant Foods Hum Nutr. 2006 Jun; 61(2):73-80.
Abstract. Dietary plants and herbal preparations have been traditionally used as medicine in developing countries and obtained a resurgence of use in the United States and Europe. Research carried out in last few decades has validated several such claims of use of traditional medicine plants. Popularity of pumpkin in various systems of traditional medicine for several ailments (antidiabetic, antihypertensive, antitumor, immunomodulation, antibacterial, antihypercholesterolemia, intestinal antiparasitia, antiinflammation, antalgic) focused the investigators' attention on this plant. Considerable evidence from several epidemiological studies concerning bioactivities leads have stimulated a number of animal model, cell culture studies and clinical trials designed to test this pharmacological actions. In addition, it was found that technologies such as germination and fermentation could reduce antinutritional materials and affect the pharmacological activities of pumpkin. This review will focus on the main medicinal properties and technologies of pumpkin, and point out areas for future research to further elucidate mechanisms whereby this compound may reduce disease risk.
(2) Strobl M, Patz B, Bracher F: Kürbissamen bei Störungen der Blasenfunktion. DAZ 2004;144:4010-4014.
(3) 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. Urol Int. 2015;94(3):286-95. doi: 10.1159/000362903. Epub 2014 Sep 5.
Gossell-Williams M, Davis A, O'Connor N: Inhibition of testosterone-induced hyperplasia of the prostate of Sprague-Dawley rats by pumpkin seed oil. J Med Food 2006;9:284-286.
Abstract. The oil from the pumpkin (Cucurbita pepo) seed is claimed to be useful in the management of benign prostatic hyperplasia. This investigation seeks to examine the effect of pumpkin seed oil on testosterone-induced hyperplasia of the prostate of rats. Hyperplasia was induced by subcutaneous administration of testosterone (0.3 mg/100 g of body weight) for 20 days. Simultaneous oral administration of either pumpkin seed oil (2.0 and 4.0 mg/100 g of body weight) or corn oil (vehicle) was also given for 20 days. The weights of the rats were recorded weekly, and the influence of testosterone and pumpkin seed oil on the weight gain of the rats was examined. On day 21, rats were sacrificed, and the prostate was removed, cleaned, and weighed. The prostate size ratio (prostate weight/rat body weight) was then calculated. Neither testosterone nor pumpkin seed oil had any significant influence on the weight gain of the rats. Testosterone significantly increased prostate size ratio (P < .05), and this induced increase was inhibited in rats fed with pumpkin seed oil at 2.0 mg/100 g of body weight. The protective effect of pumpkin seed oil was significant at the higher pumpkin seed oil dose (P < .02). We conclude pumpkin seed oil can inhibit testosterone-induced hyperplasia of the prostate and therefore may be beneficial in the management of benign prostatic hyperplasia.
Kim SH, Jung KI, Koh JS, Min KO, Cho SY, Kim HW: Lower urinary tract symptoms in benign prostatic hyperplasia patients: orchestrated by chronic prostatic inflammation and prostatic calculi? Urol Int 2013;90:144-149.
(4) Procida G, Stancher B, Cateni F, Zacchigna M. Chemical composition and functional characterisation of commercial pumpkin seed oil. J Sci Food Agric. 2013 Mar 30;93(5):1035-41. doi: 10.1002/jsfa.5843. Epub 2012 Aug 30.
(5) Kushawaha DK, Yadav M, Chatterji S, Srivastava AK, Watal G. Evidence based study of antidiabetic potential of C. maxima seeds - In vivo. J Tradit Complement Med. 2017 Jan 17;7(4):466-470. doi: 10.1016/j.jtcme.2016.12.001
Abstract. Objective: In vitro antidiabetic efficacy of Cucurbita maxima seed extract (CMSE) has already been studied in our previous findings. Thus, in order to validate these findings in biological system, in vivo antidiabetic activity of aqueous extract was investigated in normal as well as diabetic experimental models. Methods: Variable doses of extract were administered orally to normal and STZ induced mild diabetic rats during fasting blood glucose (FBG) and glucose tolerance test (GTT) studies. In order to determine the extract's antidiabetic potential long-term FBG and post prandial glucose (PPG) studies were also carried out. Results: Most effective dose of 200 mg kg-1 of CMSE decreases the blood glucose level (BGL) in normal rats by 29.02% at 6 h during FBG studies and 23.23% at 3 h during GTT. However, the maximum reduction observed in BGL of mild diabetic rats during GTT the same interval of time was 26.15%. Moreover, in case of severely diabetic rats a significant reduction of 39.33% was observed in FBG levels whereas, in case of positive control, rats treated with 2.5 mg kg-1 of glipizide, a fall of 42.9% in FBG levels was observed after 28 days. Results of PPG level also showed a fall of 33.20% in severely diabetic rats as compared to the positive control showing a fall of 44.2% at the end of the 28 days. Conclusion: Thus, the present study validate the hypoglycemic and antidiabetic effect of CMSE and hence this extract could be explored further for developing as a novel antidiabetic agent.
Pumpkin seeds 
Medicinal bioactivites and allergenic properties of pumpkin seeds: review upon a pediatric food anaphylaxis case report.
Edible seeds from Cucurbitaceae family as potential functional foods: Immense promises, few concerns.
D7-sterols
