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Hemp Seed Oil — Research Profile

Evidence:Emerging
·

This content is for informational purposes only and does not constitute medical advice. Statements about dietary supplements have not been evaluated by the FDA and are not intended to diagnose, treat, cure, or prevent any disease. Individual results may vary — consult your healthcare provider before starting any supplement. Full disclaimer

Hemp seed oil is a food oil with polyunsaturated fats.

Hemp seed oil is a food oil with polyunsaturated fats. A small eczema study reported symptom changes, but robust evidence for treating skin disease or preventing cardiovascular disease is lacking. It is not CBD oil, and contamination controls still matter.

Hemp seed oil can supply dietary fats, but an “optimal” fatty-acid ratio and broad heart, immune or eczema treatment benefits are not established.

Evidence:RCT (2005) · n=20 · moderate confidence[#1]. See full reference list below.

Key Facts

What it is
A seed oil containing linoleic acid, alpha-linolenic acid and smaller amounts of gamma-linolenic acid; distinct from CBD or cannabis extracts
Primary benefits
  • Supplies dietary polyunsaturated fats
  • Small exploratory study of atopic-dermatitis symptoms
  • Clinical heart and immune benefits remain uncertain
Typical dosage
No established therapeutic dose; food use and trial preparations differ
Evidence level
Emerging
Safety profile
Generally Safe

Time to Effect

Hours
Days
Weeks
Months
Not establishedtypical onset

A small crossover study followed participants over 20 weeks; this is not a proven response time for oral or topical use.

What the Research Says

The direct human evidence is limited. Callaway and colleagues compared dietary hempseed oil with olive oil in a small single-blind crossover study. Participants reported changes in dryness, itchiness and medication use, while the skin-water-loss measure did not reach statistical significance [1]. These results require replication and cannot establish topical treatment efficacy.

The oil’s fatty-acid composition does not establish an optimal dietary ratio or broad cardiovascular protection. Studies of hemp oil combined with terpenes and ginger [7], or with evening primrose oil and dietary changes [8], cannot isolate the effect of hemp seed oil. A beta-carotene tablet study is not evidence for this oil and has been removed.

Benefits of Hemp Seed Oil

  • Atopic dermatitis — a small 20-week crossover study reported improved self-rated dryness, itchiness and medication use after oral hempseed oil. The measured skin-water-loss change was not statistically significant, and the study does not establish topical efficacy [1].
  • Fatty-acid composition — hemp oil provides linoleic acid, ALA and some GLA, but no universally optimal omega-6:omega-3 ratio has been established [3].
  • Combination research — trials combining hemp oil with other oils, dietary changes, terpenes or ginger cannot establish an effect of hemp oil alone [7,8].

Our Top Hemp Seed Oil Picks

As an Amazon Associate, we earn from qualifying purchases. Some links below are affiliate links — this doesn't affect our editorial independence or product ratings. How we evaluate products

NOW Foods Hemp Seed Oil 1000mg
NOW Foods Hemp Seed Oil 1000mg
NOW
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OverallForm: SoftgelPrice: $14.99 · $0.12 / count
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Piping Rock Hemp Seed Oil 1400mg
Piping Rock Hemp Seed Oil 1400mg
Piping Rock
BudgetForm: SoftgelPrice: $15.29 · $0.08 / count
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Manitoba Harvest Hemp Seed Oil Capsules 1000mg
Manitoba Harvest Hemp Seed Oil Capsules 1000mg
Manitoba Harvest
Best BrandForm: SoftgelPrice: $17.99 · $17.99 / count
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Carlyle Hemp Oil Capsules 1400mg
Carlyle Hemp Oil Capsules 1400mg
Carlyle
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DEVA Vegan Virgin Hemp Seed Oil Capsules
DEVA Vegan Virgin Hemp Seed Oil Capsules
DEVA
VeganForm: Capsule (vegan plant cellulose)Price: $9.99 · $0.11 / count
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See all hemp seed oil products →
Did you know?

The direct human evidence is limited.

Forms of Hemp Seed Oil

Hemp Seed Oil supplement forms compared by bioavailability and best use
FormBioavailabilityBest For
Cold-Pressed Liquid OilHighFood use; protect from heat, light and air and follow the product’s storage instructions.
Softgel CapsulesHighConvenience; capsule amounts are not interchangeable with tablespoons used in food or research.
Topical Hemp Seed OilModerate (local)Cosmetic use; oral evidence does not establish topical eczema treatment, and skin irritation or allergy is possible.

Dosage Recommendations

General recommendation: No evidence-based therapeutic dose is established.

Timing: With meals for optimal fatty acid absorption; can be divided into two doses (morning and evening) for GI tolerance • Take with food for best absorption.

Dosage by Condition

Food or exploratory research use
Product composition and study regimens differ. Do not equate a few capsules with the oil quantities used in a dietary study.Emerging

Upper limit: No established upper intake limit; a suggested tablespoon maximum is not a validated safety threshold.

Medication Interactions & Contraindications

Drug Interactions

blood-thinners
minor
blood-thinners
Hemp seed oil's omega-3 content has mild antiplatelet activity. At standard doses (1-2 tablespoons), the interaction is minimal. Monitor INR if using high doses and report unusual bruising to your physician.
immunosuppressants
minor
immunosuppressants
GLA in hemp seed oil modulates immune function via prostaglandin pathways. While no clinical interactions are documented, inform your transplant team if you begin hemp seed oil supplementation.

Who Should NOT Take This

Hemp seed allergy(absolute)
Individuals with confirmed hemp seed allergy must avoid hemp seed oil. Cross-reactivity with other Cannabis sativa products is possible. Symptoms may include hives, GI distress, or anaphylaxis in severe cases.
Upcoming surgery(relative)
Disclose all supplements to the surgical team and follow their instructions; a universal one-week stop rule for hemp seed oil is not established.
Active immunosuppressive therapy(relative)
Evidence on concentrated supplemental use with immunosuppressive treatment is limited. Review the exact product with the treating team rather than assuming a proven immune effect.

This information is for educational purposes only. Always consult your healthcare provider before starting or stopping any supplement, especially if you take prescription medications.

Side Effects and Safety

Safety profile: Generally Safe

Potential Side Effects

  • Digestive upset can occur, especially with larger amounts.
  • Avoid if allergic to hemp seed.
  • Contamination with cannabinoids is possible; product testing reduces uncertainty but cannot guarantee a negative drug test.

Drug & Supplement Interactions

  • Clinical interaction research on hemp seed oil itself is limited. Do not import CBD drug-interaction claims into seed oil or assume every combination is safe. Review use with the treating clinician when on anticoagulants or immunosuppressive treatment.

Do not exceed: No established upper intake limit; a suggested tablespoon maximum is not a validated safety threshold.

Check Hemp Seed Oil interactions with other supplements →
BenefitsDosage GuideSide EffectsTypes & FormsResearchFAQ

Related Conditions

Skin HealthInflammationHeart HealthEczema (Atopic Dermatitis)Immune Function

Commonly Taken Together

+
Evening Primrose Oil
Both support eczema
See top evening primrose oil products →
+
Omega-3
Both support immune-function
See top omega-3 products →
+
Black Seed Oil
Both support inflammation
+
Krill Oil
Both support heart-health
See top krill oil products →

Related Guides

Eczema & Skin Barrier Supplements Guide
An evidence-cautious look at supplements studied around eczema and the skin barrier — omega-3s, evening primrose, probiotics, vitamin D — framed as support, not a substitute for dermatology.
Omega-3 & Healthy Fats Supplements Guide
How to choose among omega-3 and fat supplements — fish oil, krill, cod liver, flax, algae, MCT — by EPA/DHA content, conversion, and quality, with an oxidation caution.

Related Supplements

Evening Primrose OilModerate

Bottom line: EPO at 2-6 g daily provides anti-inflammatory GLA for skin barrier support, with mixed evidence for eczema but consistent benefits for skin hydration.

Top picks →
Omega-3Strong

Bottom line: Omega-3s have strong evidence for heart, brain, and joint health. Take 1,000-2,000mg EPA+DHA daily — choose triglyceride form fish oil or algal oil for vegans.

Top picks →
Black Seed OilModerate

Black-seed preparations have promising but limited metabolic evidence. Match any claim to the preparation studied, and review use with a clinician when taking glucose-lowering, blood-pressure, or anticoagulant medicines. [2][11]

Krill OilModerate

Krill oil is an EPA/DHA source, with no established overall clinical superiority to fish oil. Compare active omega-3 content, tolerance, cost and allergy considerations.

Top picks →
Ceramides (Phytoceramides)Moderate

Oral ceramide extracts may modestly improve dry-skin hydration. Match the studied extract and active content; short cosmetic trials do not establish eczema treatment or long-term safety. [1,5,6]

Looking for the best hemp seed oil supplement?

We analyzed and ranked the top products based on form, dosage, third-party testing, and value.

See Our Top Picks

Frequently Asked Questions

Does hemp seed oil contain THC or CBD?

Properly produced hemp seed oil is distinct from cannabinoid-rich extracts and is not expected to have psychoactive effects. Trace contamination can occur during processing, so do not assume every product is entirely free of THC or CBD. Legal requirements also vary by jurisdiction.

What makes hemp seed oil's fatty acid ratio special?

The commonly reported ratio describes its linoleic-acid and ALA content. There is no established single optimal ratio for every person, and omega-6 fats should not all be characterized as inflammatory. Overall diet and amounts matter more than a marketing ratio.

Evidence:Review (1996) · low confidence[#3]. See full reference list below.

Can hemp seed oil help with eczema?

One small oral crossover trial reported improved dryness and itching, but the objective skin-water-loss result was not statistically significant. The evidence is preliminary and does not show that topical oil is an effective eczema treatment or a replacement for prescribed care.

Evidence:RCT (2005) · n=20 · moderate confidence[#1]. See full reference list below.

How does hemp seed oil compare to evening primrose oil?

Both may contain GLA, but amounts vary and evening primrose oil generally supplies a higher proportion. A composition difference does not establish which oil produces better clinical outcomes. Neither should be selected solely on an “optimal ratio” claim.

Will hemp seed oil show up on a drug test?

A negative drug test cannot be guaranteed for any product that might contain trace THC. If testing matters, review the exact batch documentation and the rules of the testing program; a brand reputation or “hemp seed” label alone is insufficient.

How should I store hemp seed oil?

Follow the exact label’s refrigeration and use-by instructions. Protect the oil from light, air and heat; a universal 8-12 week shelf life does not apply to every formulation or package.

Can I use hemp seed oil on my skin directly?

Some products are sold for cosmetic skin use, but oral research does not establish topical efficacy or guarantee that pores will not clog. Avoid use with hemp allergy and stop if irritation occurs; do not replace established eczema care.

Continue Reading

Condition Guide

Skin Health

Specific collagen-peptide trials and a meta-analysis suggest improvements in some skin measures, but effects differ by outcome and formulation. In the 69-woman collagen trial, elasticity improved while moisture findings were not statistically significant. A small oral hyaluronan trial found a wrinkle signal. These studies do not establish a percentage reversal of skin aging or replace sun protection.

Product Comparison

Best Hemp Seed Oil Supplements

See our top ranked products

References

  1. RCTCallaway J, Schwab U, Harvima I, Halonen P, Mykkanen O, Hyvonen P, Jarvinen T (2005). Efficacy of dietary hempseed oil in patients with atopic dermatitis. Journal of Dermatological Treatment. DOI PubMed
  2. ReviewDeferne JL, Pate DW (1996). Hemp seed oil: A source of valuable essential fatty acids. Journal of the International Hemp Association.
  3. ObservationalFarì G, Megna M, Scacco S, Ranieri M, et al. (2023). Hemp Seed Oil in Association with β-Caryophyllene, Myrcene and Ginger Extract as a Nutraceutical Integration in Knee Osteoarthritis: A Double-Blind Prospective Case-Control Study.. Medicina (Kaunas, Lithuania). DOI PubMed
  4. RCTRezapour-Firouzi S, Arefhosseini SR, Mehdi F, Mehrangiz EM, et al. (2013). Immunomodulatory and therapeutic effects of Hot-nature diet and co-supplemented hemp seed, evening primrose oils intervention in multiple sclerosis patients.. Complementary therapies in medicine. DOI PubMed