This article discusses the evidence for these and other possible health benefits, along with side effects to be aware of and precautions to take when adding flaxseed oil to your diet.

What Is Flaxseed Oil Used For?

Flaxseed oil is used for a range of health concerns, including reducing inflammation and preventing cancer. It contains many active compounds that are thought to provide benefits, including: 

Omega-3 fatty acids Minerals, including calcium and magnesium

Here are some of the potential health benefits of flaxseed oil and evidence to back up these claims. 

Lowers Inflammation 

Because flaxseed oil contains omega-3 fatty acids, it may reduce inflammation. One animal study published in 2013 found flaxseed oil offered impressive inflammation-lowering benefits. However, studies in humans have yielded mixed results. 

One analysis of multiple human studies found flaxseed contained compounds helpful for reducing C-reactive protein (an inflammation marker) in some of the study participants.

The analysis suggests that flaxseed oil may affect people differently and, therefore, more research is needed to determine its effects on inflammation in the general population.

Promotes Heart Health

Studies have found that flaxseed oil supplements can increase levels of omega-3 fatty acids in the body, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

EPA and DHA are essential compounds for promoting a healthy heart and preventing heart disease. ALA is converted to EPA and DHA in the body, while flaxseed naturally contains omega-3 fatty acids.

Improves Gut Health 

Flaxseed oil has laxative properties. In a study of 50 hemodialysis patients, daily supplementation of flaxseed oil helped relieve constipation.

A small 2012 study of people with irritable bowel syndrome (IBS) found that flaxseeds were helpful in reducing IBS symptoms, including constipation and diarrhea.

Improves Skin 

ALA is a powerful antioxidant. It is often promoted by cosmetic manufacturers has having “anti-aging” properties. 

Research shows flaxseed oil may help reduce skin cell inflammation and promote the regeneration of skin.

Aids in Weight Loss 

A 2012 report in the journal Appetite finds that flaxseed supplements can help suppress appetite, allowing for reduced food intake and weight loss. It’s thought that the soluble fiber (a type of fiber that absorbs water in the gut) in flaxseed promotes a feeling of fullness.

Reduces Menopause Symptoms 

There is some evidence that flaxseed oil may help with menopause symptoms. One 2015 study of 140 menopausal women using flaxseed oil supplements showed a decrease in hot flashes and an increase in quality of life.

Possible Side Effects

When taken in the right doses and in the short term, flaxseed oil is usually safe for most adults. Large doses can cause diarrhea and loose stools. Allergic reactions are also possible. 

A 2010 study in The American Journal of Clinical Nutrition suggests that ALA can increase the risk of prostate cancer or promote tumor growth. Additional research shows ALA from animal-based foods that are high in saturated fats might be linked to prostate cancer.

But ALA itself might not be the culprit. Other substances in those foods, such as the hormones and pesticides in meat, might promote tumor growth.

However, much of this research is speculative and other research suggests flaxseed can actually benefit men’s prostate health. 

There is limited evidence on the safety of flaxseed oil when applied topically on skin or hair. However, a small study of a topical flaxseed oil gel found it safe and effective for carpal tunnel syndrome.

Contraindications

People who shouldn’t use flaxseed oil include:

Pregnant women: It may have adverse effects in pregnancy, including an increased risk for premature birth. Children: There has not been enough evidence on the safety of flaxseed oil when taken by children, although it is likely safe for children to consume small amounts of flaxseed. Breastfeeding mothers: There isn’t enough reliable information about the safety of flaxseed oil for women who are breastfeeding. People with bleeding disorders: There is some debate about whether flaxseed oil may increase the risk of bleeding. If you have a bleeding disorder, talk to your healthcare provider before using flaxseed oil in food, in supplement form, or as a topical treatment. Surgery: Flaxseed oil should be stopped at least two weeks before surgery and throughout the initial recovery period to prevent bleeding. People taking blood clotting drugs: Taking flaxseed oil with medications that slow down blood clotting (such as aspirin, diclofenac, or warfarin) may increase the risk of bleeding and bruising. 

Ask your healthcare provider if a flaxseed oil supplement is right for you.

Dosage and Preparations

There are no standard dosing guidelines for flaxseed oil. The recommended dosage varies based on the manufacturer.

Flaxseed oil is available as an oil used in food preparation and in gelcap supplements. Here are some ways to use it:

Use as a salad oil, or in cold sauces. Add to juice, shakes, or smoothies. Do not use in stir-fries or when baking. When exposed to heat, the oil can form harmful chemicals. Apply it topically or add it to your favorite skin cream to increase moisture in the skin and improve skin health.  Apply to hair to promote growth and shine.  

What to Look For

You may find flaxseed oil in the refrigerated section of your health food store or on store shelves. Some brands add antioxidants to make their products shelf-stable, meaning they don’t need refrigeration until opened.

Look for cold-pressed oil packaged in an opaque bottle to protect it from the light. The oil should be a clear or golden-yellow color. Some oils, known as high-lignan oils, contain particles of ground flaxseed and may appear to have dirt or grit in it, which is normal.

Fresh flaxseed oil has a mild, nutty aroma reminiscent of sunflower or sesame seeds and tastes crisp and mildly nutty. Oil that is cloudy, smells fishy or like fried oil, or has a bitter or burnt flavor is rancid and should not be used. If you notice this or the product is past its expiration date, throw it out.

Summary

Flaxseed oil, made from ground flax seed, is widely credited with aiding in inflammation, menopause, weight loss, gut health, heart health, and skin health. Science offers some support for these claims, but flaxseed oil is not a miracle cure for any condition.

When taken in the right dose, flaxseed oil has few side effects, but there is limited research on its safety when applied topically. Flaxseed oil can be added to juice, salads, or smoothies as well as to body cream or your hair.

If you’re pregnant, breastfeeding, have an upcoming surgery, or have a bleeding disorder, you should consult your healthcare provider before trying this supplement.

A Word From Verywell

Flaxseed oil is high in omega-3 fatty acids and other healthful compounds shown to have a variety of health benefits. However, most of the research on this has been on animal models, and studies on humans have been limited.

Be sure to speak with your healthcare provider before using flaxseed oil to ensure that it is appropriate for you.

If you decide to supplement with flaxseed oil, start with just a little to see how it affects your digestion. Then gradually increase the amount you take and watch for side effects.