Flaxseed Oil Benefits, Nutrition, Dosage and Side Effects - Dr. Axe

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Flaxseed Oil Benefits for Digestion, Skin & Heart Health

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Flaxseed oil benefits - Dr. Axe

If you’re looking to increase your omega-3 intake, flaxseed oil is one of the best vegan or vegetarian choices. In fact, flaxseed is the richest plant source of omega-3 fatty acids, with it being particularly rich in  a-linolenic acid (ALA).

Research suggests that flaxseed oil has potential health benefits related to heart health, cancer, inflammation levels, digestive issues, skin health and more. Today, you’ll see flaxseed oil and flaxseed oil supplements online or in your local health food store. Just like fish oil, people use flaxseed oil for its healthy fats and its benefits for the heart.

Flaxseed oil, also known as flax oil or linseed oil, comes from the seeds of the flax plant (Linum usitatissimum). The flaxseeds are ground and pressed to release the oil. Flaxseed is actually one of the oldest crops, as it has been cultivated since the beginning of civilization. The Latin name for flaxseed means “very useful,” and that’s because every part of the flaxseed plant is utilized.

Let’s learn about flaxseed oil’s main benefits for health as well as how to use it in one’s diet.

1. Rich in omega-3 fatty acids

Studies show that flaxseed oil is low in saturated fatty acids, moderate in monounsaturated fatty acids and rich in polyunsaturated fatty acids.

Flaxseed oil contains omega-3 and omega-6 fatty acids, which are both polyunsaturated fatty acids (PUFAs) that the body is unable to produce, but are necessary to human health. It’s highly important to get the right balance of PUFAs since omega-3 fatty acids help reduce inflammation, while many omega-6 fatty acids contribute to inflammation.

With flaxseed oil, the omega-6:omega-3 ratio is 0.3:1, which is exactly in line with how much of each type of fat you should be consuming.

Among its omega-3 fatty acids, flaxseed oil only contains ALA, which the body converts into eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), which are the omega-3 fatty acids readily available in fish oil.

A typical serving size of flaxseed oil — one tablespoon (13.6 grams) — contains about 9.2 grams of polyunsaturated fatty acids, of which 7.3 grams is ALA.

2. Relieves constipation and diarrhea

Constipation is slower than normal movement of food waste through the digestive tract. It’s generally accompanied by a variety of symptoms, such as bloating, gas, back pain or fatigue. One of the main folk or traditional uses for flaxseed oil, by acting as a lubricant to the colon, has been natural constipation relief.

A 2015 study gave either flaxseed oil, olive oil or mineral oil to 50 constipated patients on hemodialysis over the course of four weeks. While mineral oil is often used for constipation, this study also demonstrated that the daily use of flaxseed oil (and olive oil) was as effective as mineral oil for relieving constipation.

Not only that, but flaxseed oil benefits those suffering from diarrhea as well. A 2015 animal study published in the Journal of Ethnopharmacology found that it has dual effectiveness at relieving constipation and stopping diarrhea, showing flaxseed oil benefits the digestive system in multiple ways.

Note that more research is still needed regarding using flaxseed oil for constipation or diarrhea, as studies thus far are limited to being animal-based or with people with certain health conditions.

3. Aids in weight loss

Since flaxseed oil lubricates the colon and works as a natural laxative, it’s excellent at keeping things moving in the digestive system. By helping your body to get rid of food and wastes more quickly, it helps your body to detoxify and shed excess weight.

In fact, a 2015 study published in Nutrition Journal found that flaxseed oil added to a weight loss diet not only helped participants lose weight, but it also reduced inflammation markers.

4. Supports heart health

There’s evidence that eating foods high in alpha-linolenic acid like flaxseed oil might help prevent and treat heart disease. One 2023 review suggested that ALA may play a role in reducing the risk of cardiovascular events because of its anti-hypertensive, anti-atherosclerotic and cardioprotective effects.

Another study found that women who ate high levels of ALA (1.5 grams per day) had a 46 percent lower risk of sudden cardiac death than those who ate the lowest amount of ALA (about half a gram per day).

A study compared flaxseed oil to safflower oil (which is high in omega-6 fatty acids), and it found that supplementing with one tablespoon of flaxseed oil for 12 weeks helped produce much lower blood pressure levels than the safflower oil supplementation.

5. May fight cancer

In a 2015 study, researchers found that ALA contained in flaxseed oil helped reduce growth of breast cancer cell lines by modifying signaling pathways. More research is needed to determine the mechanism of action.

Another study in the journal Nutrition and Cancer supports the use of flaxseed oil as an inexpensive complementary therapy for a wide range of breast cancers. The research showed that the ALA in flaxseed oil helped reduce cancer cell growth and induced apoptosis, which is programmed cell death of cancer cells.

An animal study in 2015 also showed that mice given flaxseed oil for 40 days saw the prevention of cancer spread and lung tumor growth.

Just note that these flaxseed oil for cancer studies are limited to animal and test tube studies at present.

6. Supports skin health

While no studies exist that examine flaxseed oil being used topically for skin health, supplementation of flaxseed oil for skin health has been studied.

A small 2011 study concerned 13 women who supplemented with flaxseed oil for 12 weeks. By the conclusion of the study, the women noted improvements in skin hydration and smoothness as well as a reduction in skin sensitivity to irritation.

7. May treat Sjogren’s syndrome

Sjogren’s syndrome is a disorder of the immune system identified by its two most common symptoms — dry eyes and a dry mouth. A number of studies to date have suggested numerous potential associations between diet and tear film health.

One such study evaluated if oral flaxseed oil can help Sjogren’s syndrome patients. Results showed that therapy with oral flaxseed oil capsules (one or two grams per day) reduced eye surface inflammation and improved the symptoms of keratoconjunctivitis sicca (dry eye) in Sjogren’s syndrome patients.

8. Used in Ayurveda and TCM

Ayurveda practitioners use flaxseed oil to balance the skin’s pH and improve its strength and elasticity. It’s also known to improve dry skin by holding in moisture, promote wound healing and give the skin a glowing appearance.

Flaxseed is also part of an Ayurvedic diet and traditionally, it would be used in medicine as a remedy for wound healing, gastrointestinal disorders, respiratory conditions and even tumors.

Meanwhile, in Traditional Chinese Medicine, flaxseed oil is used to restore moisture in the body and counteract dryness that occurs in colder weather. Flaxseeds and flaxseed tea are also used to improve kidney and liver health.

How to use flaxseed oil

You can find flaxseed oil easily in your local health food store or even online. It’s best to purchase a cold-pressed and organic flaxseed oil from a well-respected brand. Whichever brand you go with, flaxseed oil should be stored in an opaque bottle (usually black) to reduce oxidation. You can also buy flaxseed oil in capsule form if you’re looking to avoid the taste.

One of the most convenient flaxseed oil benefits is its versatility. With its nutty, slightly sweet flavor, it’s fairly easy to add to your diet.

Here are some ways to use flaxseed oil in your diet:

  • It can be used in place of other oils for salad dressings and sauces.
  • Add to smoothies and protein shakes.
  • Like flaxseed meal, mix with yogurt or oatmeal.
  • Use in place of butter on rice, potatoes or toast.

In terms of storage, flaxseed oil must always be kept in the refrigerator to retain freshness. To prevent oxidation and rancidity, it’s also key to keep the bottle tightly closed.

For maximum freshness, it’s ideal to consume your flaxseed oil within six to eight weeks after opening. If you’re not going to take flaxseed daily or are prone to forgetfulness, it can be a good idea not to purchase an overly large bottle of flaxseed oil.

Never use flaxseed oil in cooking since it’s much too easily oxidized. It’s fine to add flaxseed oil to foods after they’ve been heated, however.

Supplements and dosage

Flaxseed oil is available as a dietary supplement in capsule form. Flaxseed oil supplements are typically taken for their omega-3 fatty acid content and they are generally used to boost cardiovascular health.

The flaxseed oil dosage will vary depending on the product, but taking one to three 1,000 milligram flaxseed oil capsules daily is commonly recommended. If you are taking too much flaxseed oil, you may notice digestive problems, like loose stool and diarrhea. If that’s the case, reduce your dosage.

If you are taking flaxseed oil supplements while on medication or along with other dietary supplements, make sure to consult your healthcare professional about possible interactions.

Risks and side effects 

Flaxseed oil supplements seem to be well-tolerated with few flaxseed oil side effects reported. Flaxseed oil is likely safe for most people when taken by mouth in appropriate amounts. Large doses of two tablespoons (30 grams) or higher per day can cause loose stools and diarrhea.

If you’re being treated with any of the following medications, you should not use flaxseed oil or other omega-3 fatty acid supplements without talking to your healthcare professional first:

  • Blood-thinning medications (anticoagulant): Omega-3 fatty acids can strengthen the effects of blood-thinning medications.
  • Blood sugar-lowering medications: Omega-3 fatty acid supplements may increase fasting blood sugar levels, which may increase your need for the medications.
  • Cyclosporine: Taking omega-3 fatty acids during cyclosporine (Sandimmune) therapy may reduce the toxic side effects associated with this medication in transplant patients, such as high blood pressure and kidney damage, but also may have adverse effects.

On the positive side, some possible good interactions with flaxseed oil have been seen with the following:

  • Etretinate and topical steroids: Adding omega-3 fatty acids (specifically EPA) to the drug therapy etretinate (Tegison) and topical corticosteroids may improve symptoms of psoriasis.
  • Cholesterol-lowering medications: Increasing the amount of omega-3 fatty acids in your diet may help a group of cholesterol-lowering medications known as statins work more effectively.
  • Nonsteroidal anti-inflammatory drugs (NSAIDs): In an animal study, treatment with omega-3 fatty acids reduced the risk of ulcers from NSAIDs, including ibuprofen (Motrin or Advil) and naproxen (Aleve or Naprosyn). It’s likely that more research will show that omega-3 fatty acids have the same effects in people.

Pregnant women should also avoid flaxseed oil since it may increase the risk of premature birth. Check with your healthcare before consuming flaxseed oil if you are currently nursing.

Taking flaxseed oil and fish oil at the same time can possibly cause the blood to become too thin. Check with your healthcare before taking both at the same time.

If you have any other health concerns or are currently taking any other prescription or non-prescription medicines, including supplements, then speak with your healthcare professional before incorporating flaxseed oil into your diet.

Conclusions

  • Flaxseed oil is high in omega-3 fatty acids (specifically ALA) and has been shown to support heart and skin health, potentially relieve constipation and fight cancer, and may even boost weight loss efforts.
  • Flaxseed oil is versatile and easy to add to the diet, including as a salad dressing oil, added to smoothies and drizzled over cooked foods.
  • Including just one or two servings of flaxseed oil may offer several valuable health benefits.

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