- What other names is Flaxseed Oil known by?
- What is Flaxseed Oil?
- How does Flaxseed Oil work?
- Are there safety concerns?
- Are there any interactions with medications?
- Dosing considerations for Flaxseed Oil.
nutrition. Flaxseed oil contains the essential omega-3 fatty acid alpha-linolenic acid (ALA).
People take flaxseed oil by mouth for constipation, osteoarthritis, pneumonia, rheumatoid arthritis, cancers including breast cancer and prostate cancer, anxiety, benign prostatic hyperplasia (BPH), vaginal infections, attention deficit-hyperactivity disorder (ADHD), bipolar disorder, exercise performance, an ovary disorder called polycystic ovary syndrome (PCOS), diabetes, weight loss, hardening of the arteries (atherosclerosis), heart disease, HIV/AIDS, high triglyceride levels, high cholesterol and other fats in the blood, high blood pressure, dry skin, dry eyes, and reducing inflammation associated with a treatment for kidney disease called hemodialysis.
People apply flaxseed oil to the skin to sooth irritations or soften roughness and for carpal tunnel syndrome. It is used in the eye for dry eye.
In foods, flaxseed oil is used in salad dressings and in margarines.
In manufacturing, flaxseed oil is used as an ingredient in paints, varnishes, linoleum, and soap; and as a waterproofing agent. When it is used for manufacturing purposes, flaxseed oil is usually referred to as linseed oil.
Possibly Effective for...
- Carpal tunnel syndrome. Research suggests that applying flaxseed oil to the wrist twice daily for 4 weeks improves symptoms and wrist function in people with carpal tunnel syndrome who wear a wrist splint at night.
Possibly Ineffective for...
- Bipolar disorder. Research suggests that taking flaxseed oil daily for 16 weeks does not improve symptoms of mania or depression in children with bipolar disorder.
- Diabetes. Research suggests that flaxseed oil does not lower blood sugar or improve insulin levels in people with type 2 diabetes.
- High cholesterol. Early research suggests that taking flaxseed oil daily for 3 months lowers total cholesterol in people with high cholesterol. However, this early research is not reliable. More reliable research suggests that flaxseed oil does not reduce cholesterol levels in people with high cholesterol and high triglycerides. When taken in combination with safflower oil, flaxseed oil seems to modestly reduce total and low-density lipoprotein (LDL or "bad") cholesterol in people with at least one risk factor for heart disease. But the combination of oils does not seem to work as well as canola oil that has been enriched with docosahexaenoic acid (DHA).
- Rheumatoid arthritis (RA). Taking flaxseed oil daily for 3 months does not seem to improve symptoms of pain and stiffness, and has no effect on laboratory tests that measure the severity of RA.
Insufficient Evidence to Rate Effectiveness for...
- "Hardening of the arteries" (atherosclerosis). There is some evidence that increasing the amount of linolenic acid in the diet can help to prevent hardening of the arteries. Flaxseed oil contains linolenic acid. Therefore some people suggest that flaxseed oil might prevent atherosclerosis. Though this assumption seems reasonable, there has been no research yet to prove it is correct.
- Attention deficit-hyperactivity disorder (ADHD). Early research suggests that taking flaxseed oil in combination with vitamin C might improve attention, impulsiveness, restlessness, and self-control in children with ADHD.
- Breast cancer. Women who have higher levels of alpha-linolenic acid in their breast tissue seem to be less likely to get breast cancer. Scientists think that high intake of alpha-linolenic acid might protect against breast cancer. Flaxseed oil is one source of alpha-linolenic acid. However it is not known if increasing flaxseed oil intake will help to prevent breast cancer.
- Heart disease. Men and women who consume more alpha-linolenic acid in their diet seem to have a reduced risk of having a heart attack. Also, higher dietary intake of alpha-linolenic acid seems to reduce the risk of having a second heart attack in people who have already had one heart attack. Also, people with existing heart disease who consume more alpha-linolenic acid in their diet seem to have a lower risk of dying from heart disease. Flaxseed oil is one source of alpha-linolenic acid. However, research has not directly measured the effect of flaxseed oil intake on heart disease outcomes. It is also not known if flaxseed oil supplements have the same effects as flaxseed oil from food.
- Dry eyes. Some early research suggests that taking flaxseed oil might reduce irritation and symptoms of dry eyes in people with a condition called Sjögren's syndrome. Also, using a specific product containing fish oil plus flaxseed oil (TheraTears Nutrition, Advanced Vision Research) might reduce symptoms of dry eye and increase tear production.
- Dry skin. There is inconsistent evidence about the effects of flaxseed oil for dry skin. Some research suggests that taking flaxseed oil by mouth with vitamin C daily for 12 weeks does not improve skin moisture in women with dry skin. However, other research suggests that taking flaxseed oil by mouth for the same length of time can improve skin moisture and roughness.
- Exercise performance. Lower-quality research suggests that alpha-linolenic acid, a chemical in flaxseed oil, does not improve muscle strength in older adults. It is not known if flaxseed oil affects exercise performance.
- Treatment for kidney disease called hemodialysis. Hemodialysis can result in inflammation in the body. This inflammation can lead to complications or increase the risk of death in people undergoing hemodialysis. Research suggests that taking flaxseed oil twice daily for 120 days reduces inflammation in people undergoing hemodialysis. But it's not clear if flaxseed oil directly reduces the risk of complications or death in these people.
- HIV/AIDS. Early research suggests that taking a formula containing arginine, yeast RNA, and alpha-linolenic acid, a chemical in flaxseed oil, improves weight gain, but not immune function in people with HIV. The effects of flaxseed oil alone on HIV are not clear.
- High blood pressure. There is inconsistent evidence regarding the effects of flaxseed oil on blood pressure. Population research shows that higher intake of flaxseed oil as part of the diet is linked with a lower risk of developing high blood pressure. Also, early research suggests that flaxseed oil supplements can lower blood pressure in men with high cholesterol and normal blood pressure. But it is not clear if flaxseed oil lowers blood pressure in people with high blood pressure. Also, some conflicting research suggests that dietary or supplemental flaxseed oil does not lower blood pressure.
- An ovary disorder known as polycystic ovary syndrome (PCOS). Research suggests that taking flaxseed oil for 6 weeks might lower triglyceride levels, but does not affect weight, blood sugar, or cholesterol levels in women with PCOS.
- Pneumonia. Consuming alpha-linolenic acid in the diet seems to be linked to a reduced risk of developing pneumonia. Flaxseed oil is one source of alpha-linolenic acid. However, research has not directly measured the effect of flaxseed oil intake on pneumonia outcomes. It is also not known if flaxseed oil supplements have the same effects as flaxseed oil from food.
- Prostate cancer. Research is inconsistent on the effect of the flaxseed oil ingredient, alpha-linolenic acid, in prostate cancer. Some research suggests that high dietary intake of alpha-linolenic acid is linked with an increased risk for prostate cancer. Other research suggests high intake or high blood levels of alpha-linolenic acid is not linked with the overall risk of prostate cancer. However, extra alpha-linolenic acid might make existing prostate cancer worse. The source of alpha-linolenic acid appears to be important. Alpha-linolenic acid from dairy and meat sources has been positively linked with prostate cancer. Alpha-linolenic acid from plant sources, such as flaxseed or flaxseed oil, does not affect prostate cancer risk.
- Vaginal problems.
- Weight loss.
- Other conditions.
Quick GuideVitamin D Deficiency: How Much Vitamin D Is Enough?
Large doses of 30 grams per day and higher can cause loose stools and diarrhea. Allergic reactions have occurred while taking flaxseed oil.
Some men worry that taking flaxseed oil might increase their chance of getting prostate cancer because of the alpha-linolenic acid that flaxseed oil contains. Researchers are still trying to figure out the role of alpha-linolenic acid in prostate cancer. Some studies suggest that alpha-linolenic acid may increase risk or make existing prostate cancer worse, but other studies find no connection. Nevertheless, the alpha-linolenic acid in flaxseed oil does not seem to be a problem. Alpha-linolenic acid from plant sources, such as flaxseed, does not seem to affect prostate cancer risk, although alpha-linolenic acid from dairy and meat sources has been linked in some studies with prostate cancer.
Flaxseed oil is POSSIBLY SAFE when applied to the skin in the short-term. Flaxseed oil has been used safely on the wrist for up to 4 weeks.
Special Precautions & Warnings:Children: Flaxseed is POSSIBLY SAFE for children when taken by mouth, short-term. Flaxseed oil has been safely taken by mouth for up to 3 months by children about 7-8 years old.
Pregnancy: Flaxseed oil is POSSIBLY UNSAFE when taken by mouth during pregnancy. Some research suggests that flaxseed oil might increase the chance of premature birth when taken during the second or third trimesters of pregnancy. However, other research suggests that taking flaxseed oil might be safe starting from the second or third trimester and continuing until delivery. Until more is known, pregnant women should avoid taking flaxseed oil.
Breast-feeding: There is not enough reliable information about the safety of taking flaxseed oil if you are breast feeding. Stay on the safe side and avoid use.
Bleeding disorders: Flaxseed oil might increase the risk of severe bleeding in patients with bleeding disorders. Talk to your healthcare provider before using flaxseed oil if you have a bleeding disorder.
Surgery: Flaxseed oil might increase the risk of bleeding during and after surgery. Stop using it at least 2 weeks before a scheduled surgery.
Medications that lower blood pressure (Antihypertensive drugs)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.
Flaxseed oil might lower blood pressure. Combining flaxseed oil with other drugs that lower blood pressure might increase the chance of blood pressure going too low.
Some medications that lower blood pressure include captopril (Capoten), enalapril (Vasotec), losartan (Cozaar), valsartan (Diovan), diltiazem (Cardizem), Amlodipine (Norvasc), hydrochlorothiazide (HydroDIURIL), furosemide (Lasix), and many others.
Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.
Flaxseed oil might slow blood clotting and increase bleeding time. Taking flaxseed oil along with medications that also slow clotting might increase the chances of bruising and bleeding.
Some medications that slow blood clotting include aspirin, clopidogrel (Plavix), diclofenac (Voltaren, Cataflam, others), ibuprofen (Advil, Motrin, others), naproxen (Anaprox, Naprosyn, others), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, ticlopidine (Ticlid), warfarin (Coumadin), and others.
APPLIED TO THE SKIN:
- For carpal tunnel syndrome: 5 drops of flaxseed oil has been applied to the wrist twice daily for 4 weeks.
Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).
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Last Editorial Review: 3/29/2011