Flaxseed (linseed) oil â cold-pressed from Linum usitatissimum seeds â is a rich plant source of omega-3 fatty acids, especially α-linolenic acid (ALA). It typically contains about 35â45% oil by weight, of which ~50â60% is ALA (with the rest mostly oleic and linoleic acids) [1].
This high ALA content makes flaxseed oil a popular vegetarian alternative to fish oil. ALA is the short-chain omega-3 that the body can convert (in part) into longer-chain EPA and DHA, which have known heart- and brain-health benefits [2, 1]. Flaxseed oil also contains vitamin E and other minor bioactives.
In recent years it has gained widespread popularity as a âsuperfoodâ supplement and culinary oil, used in salad dressings, smoothies, or taken by the spoonful. As one clinical review notes, âomega-3 fatty acids are good for the heartâ [3], and flax oil is a convenient way for vegetarians to boost their omega-3 intake.
In this article, we examine the scientific evidence for various health benefits of flaxseed oil, focusing on recent studies (last 15 years) and meta-analyses. We will explore its roles in heart and blood pressure regulation, inflammation reduction, skin and gut health, cognitive function, and more, citing authoritative sources for each claim.
Cardiovascular (Heart) Health
Flaxseed oil has been associated with several heart-healthy effects. Its chief ingredient, ALA, can be metabolized into EPA and DHA, which have cardioprotective properties [2, 1]. Mechanistically, EPA and DHA (via ALA) help stabilize heart rhythms and reduce inflammation in blood vessels.
A recent review notes that adding flaxseed oil to the diet âappears to be useful to reduce the risk of cardiovascular diseaseâ [1]. Indeed, meta-analyses and clinical trials suggest flax oil can modestly improve cardiovascular risk factors. For example, a 2022 meta-analysis of randomized trials found that daily flaxseed oil supplementation lowered systolic blood pressure by about 3.9 mmâŻHg in people with metabolic syndrome or related conditions [4]. (Diastolic pressure did not change significantly.) Even a few mm Hg drop can reduce heart disease risk over time.
Flax oil also tends to improve lipid profiles: one comprehensive review reported that ALA-rich diets (like flax oil) âscantly reduceâ total cholesterol and LDL (âbadâ) cholesterol [2], with modest rises in HDL (âgoodâ) cholesterol. In practical terms, studies have found that flax oil raises blood omega-3 levels and slightly lowers LDL and triglycerides compared to control oils [4, 2]. These effects likely stem from both ALA and antioxidants in the oil.
In line with the science, health authorities note flaxseed oilâs heart benefits: the Mayo Clinic highlights that ALA âmay benefit people with heart disease,â helping to lower high blood pressure [3]. Similarly, a meta-analysis suggests flax supplementation (oil or seed) tends to reduce total and LDL cholesterol [5].
For example, adding a tablespoon of flax oil daily was shown to reduce blood pressure significantly more than a placebo oil [6] (in one trial of 59 adults over 12 weeks). Overall, these findings support the idea that regular flaxseed oil intake can contribute to heart health.
Anti-Inflammatory Effects and Joint Health
Chronic inflammation underlies many diseases, and flaxseed oil has notable anti-inflammatory properties. This effect largely comes from ALAâs conversion into anti-inflammatory mediators.
As one review explains, the âanti-inflammatory effects of ALA have traditionally been credited to its conversion to longer-chain n-3 PUFAs, EPA and DHA,â which in turn yield resolvins and protectins that resolve inflammation [2]. Flaxseed oil is thus ârich in PUFAs [and] has anti-inflammatory, immunoregulatoryâ effects [1].
Indeed, meta-analyses confirm tangible biomarker changes: in people with metabolic syndrome, flaxseed oil supplements significantly lowered the inflammatory cytokine IL-6 and markers of oxidative stress (malondialdehyde), while raising total antioxidant capacity [7]. These shifts imply that flax oil can dampen inflammatory pathways.
Anti-Inflammatory Effects and Joint Health
In practical terms, flax oil is often used as a natural anti-inflammatory remedy. For joint issues like arthritis, the alpha-linolenic acid may help âreduce joint inflammationâ [8] (though evidence in rheumatoid arthritis is limited). The mechanisms involve dampening pro-inflammatory mediators (prostaglandins, cytokines) via ALA-derived eicosanoids [2, 1].
Consistent with this, some animal studies find that flax oil extract reduces signs of arthritis and colitis, though human data are sparse. Altogether, flaxseed oilâs anti-inflammatory properties (often attributed to its omega-3 content) mean it may aid conditions linked to inflammation, from mild muscle aches to chronic inflammatory disorders [7, 1]. (Note: flaxseed oil can also have anti-oxidant effects, which further contribute to reducing tissue inflammation [7].)
In sum, flax oilâs anti-inflammatory action is one of its primary health benefits, as reported in recent clinical analyses.
Skin Health and Barrier Function
Dietary fats strongly influence skin condition, and flaxseed oil appears to improve skin quality. In a randomized trial of women with sensitive skin, daily flaxseed oil supplementation (vs. placebo oil) led to clearer and more hydrated skin [9].
After 12 weeks, the flax oil group showed significantly increased skin smoothness and hydration, with reduced transepidermal water loss (TEWL), roughness, sensitivity, and scaling [9]. By contrast, a control oil (safflower) had smaller effects. In other words, flax oil enhanced the skinâs barrier function and moisture retention. The researchers concluded that âdaily intake of flaxseed oil modulates skin condition.â These changes are likely due to omega-3 fatty acids incorporating into skin membranes and reducing dryness and irritation [9].
Practical implications include using flax oil as part of a skincare regimen. For example, adding flax oil to the diet (or even applying it topically) may soothe eczema, acne, or dermatitis, though clinical proof is limited. Importantly, flax oilâs anti-inflammatory and antioxidant effects (as noted above) can calm skin inflammation.
Thus, flaxseed oil for skin is not just anecdote: at least one trial shows measurable improvement in skin health [9]. It may also benefit hair and nails by nourishing skin cells, although specific studies are scarce.
Digestive and Gut Health
Flaxseed oil can regulate bowel function. Although whole flaxseeds (with fiber and mucilage) are known for relieving constipation, flax oil itself has a surprising dual effect on gut motility.
In a clinical trial of constipated adults on hemodialysis, patients were given either flaxseed oil, olive oil, or mineral oil (a laxative) for four weeks. The study found that flaxseed oil was as effective as mineral oil in improving constipation symptoms [10]: stool frequency and consistency improved significantly on flax oil, just as with standard oils. In other words, consuming flax oil daily made bowel movements easier and stools softer, comparable to conventional remedies [10].
Animal studies offer more insight: flaxseed oil can act as both a laxative and an anti-diarrheal agent. In mice, oral flax oil increased the water content of feces dose-dependently (a laxative effect), yet also reduced diarrhea in toxin models [11]. The laxative action seems partly cholinergic (stimulating gut motility), while the anti-diarrheal effect involves ionic (Kâș-channel) mechanisms [11].
Thus flax oil may help normalize intestinal transit: easing constipation without causing loose stools.
In addition, the healthy fats in flax oil may support the gut lining and microbiome. By reducing gut inflammation and supplying energy, omega-3s can promote a balanced microbial ecosystem (though more research is needed).
Overall, evidence suggests flaxseed oil for digestive health: it can relieve constipation and regulate gut function [10, 11]. (For general gut health, those with mild IBS or irregularity might find a benefit by adding 1â2 tablespoons of flax oil daily.)
Cognitive and Brain Function
Omega-3 fats are famous for supporting brain health, and flaxseed oil contributes via ALA. Although mammals convert ALA to DHA inefficiently, a recent trial indicates even ALA alone can benefit cognition.
In a randomized, placebo-controlled study of healthy older adults (65â80 years), 3.7 g/day of flaxseed oil (â2.2 g ALA) for 12 weeks significantly improved verbal fluency (an executive function) compared to corn oil [12]. Specifically, participants on flax oil generated more words on a standardized test, suggesting sharper frontal-lobe function.
All other cognitive domains (memory, attention) were unchanged, but the boost in verbal fluency is notable because this skill often declines with age and predicts dementia risk [12]. The authors conclude that regular flax oil intake âimproved cognitive function, specifically verbal fluency, despite the age-related declineâ [12].
This finding aligns with the idea that plant-based omega-3 can aid brain performance. Other research (in animals) has shown flax oil or seeds can improve spatial memory, reduce neuroinflammation, and raise brain-derived neurotrophic factor, though human data are still emerging.
At minimum, flaxseed oil provides essential ALA for neuronal membranes. For those seeking cognitive benefits without fish oil, flax oil appears promising: it modestly raised omega-3 blood levels in the above trial, and yielded detectable cognitive gains [12].
Metabolic Effects (Lipid Profile and Blood Sugar)
Beyond blood pressure and inflammation, flaxseed oil influences metabolic health. Its high ALA content helps improve lipid metabolism: a meta-analysis found that dietary ALA reduces triglycerides, total cholesterol, and LDL cholesterol (though not as strongly as EPA/DHA from fish) [2]. One source notes ALA âdecrease[s] the concentrations of TG, total cholesterol, LDL and VLDLâ [2], and can modestly raise HDL. Thus, regular flax oil may aid in managing high cholesterol or high triglycerides. In practical terms, adding flax oil to a low-fat diet alongside exercise might improve a lipid panel over time.
Blood sugar control, however, seems less affected by the oil alone. Meta-analyses of flax interventions show that improvements in fasting glucose and insulin occur with whole flaxseed (rich in fiber and lignans) but not with flaxseed oil or isolated lignans [13]. In other words, studies to date indicate flaxseed oil has no significant impact on HbA1c or insulin levels [13]. People with diabetes might get more benefit from the fiber in whole seeds than from the oil.
Some preliminary evidence hints at other metabolic roles: animal studies suggest flax oil can increase fat burning in muscle and improve body composition [1]. One trial in men found that alpha-linolenicârich diets raised muscle oxidative capacity and reduced fat more than control diets [1]. While human data on weight loss are limited, these findings imply flax oil could support metabolism. Overall, flaxseed oil is safe and potentially beneficial for metabolic syndrome markers (cholesterol, blood pressure) [4, 2], though it does not replace dietary fiber for blood sugar control [13].
Bone Health and Musculoskeletal Effects
Emerging studies (mostly in animals) suggest flaxseed oil may support bone health. Diets rich in omega-3 fatty acids have been linked to higher bone density and strength. For example, rats fed a high-ALA diet (via flax oil) developed stronger femur bones and improved bone microarchitecture compared to controls [1]. Flax oil appeared to stimulate osteoblastic (bone-forming) activity and increase osteocalcin levels, a marker of bone formation [1]. In models of diet-induced bone damage, flaxseed oil âameliorated trabecular bone damageâ and increased mineral content [1].
While human trials are still needed, these animal findings point to a potential anti-osteoporotic effect of flax oil. It may be that the anti-inflammatory and pro-osteogenic milieu created by omega-3 PUFAs favors bone maintenance. Thus, flaxseed oil could conceivably contribute to bone strength and reduce osteoporosis risk, complementing its other health benefits [1].
Conclusion
In summary, flaxseed oil is a nutrient-dense oil with multiple proven health benefits. Its high omega-3 (ALA) content underlies many of its effects: improving cardiovascular risk factors (lowering blood pressure and modestly improving cholesterol), reducing inflammation, and supporting skin and brain health [1, 7, 9, 12].
Clinical studies show that even a tablespoon a day can increase blood omega-3 levels and yield real physiological changes. For example, regular intake has improved BP, arterial elasticity, and certain antioxidant markers [4, 7]. At the same time, flax oil has been shown to improve skin moisture and barrier integrity [9], normalize bowel movements [10], and enhance cognitive function in older adults [12]. Its anti-inflammatory properties (via ALA-derived mediators) help explain benefits ranging from joint comfort to anti-aging effects [2, 1].
For practical use, experts suggest incorporating 1â2 tablespoons of flaxseed oil daily into the diet. Because ALA can oxidize at high heat, itâs best used cold: drizzled on salads, mixed into smoothies or yogurt, or consumed straight. Traditional uses include mixing it with foods â for example, in parts of Germany a common snack is a roll dipped in flaxseed oil and sugar. (Modern advice would omit the sugar, of course.)
The Mayo Clinic notes flaxseed oil is generally safe at recommended amounts [3], though excessive doses can cause mild digestive symptoms. As with any supplement, people on blood thinners or with bleeding risks should consult a doctor, since flax oil can have a mild blood-thinning effect [3].
Overall, the health benefits of flaxseed oil are supported by a growing body of research. By naturally boosting omega-3 intake, flax oil can contribute to heart health, healthy skin, balanced inflammation, and more. As part of a balanced diet rich in fruits, vegetables, and whole grains, adding flaxseed oil is an easy way to harness its anti-inflammatory and omega-3 benefits. Whether in salad dressings or a smoothie, a daily spoonful of flaxseed oil may offer wide-ranging health gains â from the inside out.
Research Sources
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https://eurjmedres.biomedcentral.com/articles/10.1186/s40001-023-01203-6 - Cambiaggi L., Chakravarty A., Noureddine N., Hersberger M. The role of α-linolenic acid and its oxylipins in human cardiovascular diseases. International Journal of Molecular Sciences 2023; 24(7): 6110. DOI: 10.3390/ijms24076110.
https://pmc.ncbi.nlm.nih.gov/articles/PMC10093787/ - Mayo Clinic Staff. Flaxseed and flaxseed oil. Mayo Clinic portal, 26 March 2025. Accessed 29 April 2025.
https://www.mayoclinic.org/drugs-supplements-flaxseed-and-flaxseed-oil/art-20366457 - Mahmudiono T., Jasim S.A., Karim Y.S. et al. The effect of flaxseed oil consumption on blood pressure among patients with metabolic syndrome and related disorders: a systematic review and meta-analysis of randomised clinical trials. Phytotherapy Research 2022; 36(10): 3766-3773. DOI: 10.1002/ptr.7566.
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https://pmc.ncbi.nlm.nih.gov/articles/PMC3361740/ - Ajmera R. 6 benefits of flaxseed oil â plus how to use it. Healthline portal; updated 25 March 2024. Accessed 29 April 2025.
https://www.healthline.com/nutrition/flaxseed-oil-benefits - Tamtaji O.R., Milajerdi A., Reiner Ćœ. et al. Effects of flaxseed oil supplementation on biomarkers of inflammation and oxidative stress in patients with metabolic syndrome and related disorders: a systematic review and meta-analysis of randomised controlled trials. Clinical Nutrition ESPEN 2020; 40: 27-33. DOI: 10.1016/j.clnesp.2020.09.017.
https://pubmed.ncbi.nlm.nih.gov/33183549/ - Versus Arthritis. Flaxseed oil â uses, side-effects. Versus Arthritis portal, n.d. Accessed 29 April 2025.
https://versusarthritis.org/about-arthritis/complementary-and-alternative-treatments/types-of-complementary-treatments/flaxseed-oil - Neukam K., De Spirt S., Stahl W. et al. Supplementation of flaxseed oil diminishes skin sensitivity and improves skin barrier function and condition. Skin Pharmacology and Physiology 2011; 24(2): 67-74. DOI: 10.1159/000321442.
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https://pubmed.ncbi.nlm.nih.gov/29228348/
