Health Benefits of Flax Seeds

A serving of flax seeds provides impressive amounts of good for you nutrients like fiber, magnesium, and iron. Evidence-based benefits of flax seeds include improved digestion and reduced cancer risk.

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Flax seeds are small edible seeds from the North American flax plant. Not only do these seeds add a nutty flavor to dishes, but they're also bursting with nutrients like heart-healthy fats, fiber, plant protein, and key vitamins and minerals, per the National Library of Medicine's resource Medline Plus.

Here's more about their potential health benefits, and simple ways to incorporate flax seeds into meals and snacks.


For the past few years, flax seeds have become increasingly popular thanks to their abundance of health benefits. So far, research has found flax seeds:

May Improve Cardiovascular Health

Heart disease is the leading cause of death in the U.S., according to the Centers for Disease Control and Prevention (CDC). Flax seeds can protect heart health in several ways, mostly by reducing risk factors for heart disease, like:

  • Lowering blood pressure. A 2016 analysis of 15 studies published in Clinical Nutrition found that flax seeds reduced blood pressure, particularly when taken for 12 weeks or more.
  • Improving cholesterol levels. A 2014 study published in Biomedical Journal found that of 50 adults with high cholesterol, those who ate about three tablespoons of roasted flax seed powder daily for three months saw significant reductions in total cholesterol and LDL (aka "bad") cholesterol levels compared to a placebo group. They also saw an increase in HDL (aka "good") cholesterol levels.
  • Preventing strokes. Flax seeds are a good source of healthy fats called alpha-linolenic acid (ALA) according to Harvard Medical School— which a 2015 review in Biochimie found may help prevent stroke.

Support Digestive Health

Four tablespoons of flax seeds provide 27% of the daily recommended intake of fiber—a key nutrient for digestive health, according to the U.S. Department of Agriculture (USDA).

According to Mayo Clinic, fiber improves digestion by:

  • Regulating bowel movements
  • Reducing the risk of hemorrhoids
  • Lowering the risk of colorectal cancer

Plus, flax seeds contain both soluble and insoluble fiber, each of which improves bowel movements in slightly different ways:

  • Soluble fiber softens stool so it can pass through the digestive tract more easily
  • Insoluble fiber adds bulk to stool, which pushes waste through your gut more quickly, easing constipation.

Help Reduce Cancer Risk

Although no one food or supplement can prevent cancer, some research indicates flax seeds may reduce the risk or spread of certain cancers.

For instance, flax seeds' high fiber content can lower the chances of developing colorectal cancer. The American Institute for Cancer Research found that for every extra 10 grams of fiber consumed, there is a 7% reduced risk of colorectal cancer.

The most studied cancer in relation to flax seed consumption is breast cancer. A 2019 review published in Nutrients noted that eating flax seeds may:

  • Protect against the development of breast cancer
  • Reduce tumor growth in women with breast cancer
  • Lower the risk of death in women with breast cancer

Might Improve Blood Sugar

Since flax seeds contain ALA—a certain type of healthy fat—they may also help manage pre-diabetes. That's because ALAs appear to regulate blood sugar levels and improve insulin sensitivity, both of which reduce the risk of developing type 2 diabetes.

A 2013 study published in Nutrition Research gave 41 people with obesity and pre-diabetes either 13 grams, 26 grams, or 0 grams of flax seed daily for 12 weeks. It found that those who consumed 13 grams of flax seeds per day—about two tablespoons—saw the greatest reductions in blood sugar levels and the most significant improvement in insulin sensitivity.

Support Weight Management

Incorporating flax seeds into your diet may help with healthy, sustainable weight management thanks to their soluble fiber content. Most of the soluble fiber in flaxseeds is called mucilage (which contains 35–45 % of fiber), which, when combined with water, forms a gel-like consistency. This slows down how quickly food passes through your stomach so you stay fuller for longer, as explained in a 2015 Journal of Food Science and Technology article.

A 2017 meta-analysis published in Obesity Reviews assessed 45 studies and found eating whole flax seeds was associated with significant reductions in both body weight and waist measurement. Having a waist measurement of over 35 inches for women or 40 inches for men is associated with a higher risk for heart disease and type 2 diabetes according to the National Institutes of Health (NIH).

The review also found that eating 30 grams—about three tablespoons—of whole flax seeds daily for more than 12 weeks improved body composition in patients. Body composition tells us what percentage of our bodies are made up of fat, muscle, and other tissues, like bone.

Help Protect Against Chronic Disease

In addition to their beneficial fats and fiber, flax seeds are rich in health-protective antioxidants called polyphenols, according to a 2013 review published in the Journal of Oleo Science.

Polyphenols act like bodyguards for our cells, protecting them from damage that could eventually lead to cancer, aging and chronic diseases, including heart disease.


Flax seeds may be tiny, but they're chock full of nutrients. According to the USDA a quarter cup—about four tablespoons—of whole flax seeds supplies:

  • Calories: 224
  • Fat: 17.5g
  • Saturated Fat: 1.5g
  • Unsaturated Fat: 16g
  • Sodium: 12.6mg
  • Carbohydrates: 12g
  • Fiber: 11.5g, or 41% of the daily value (DV)
  • Added Sugars: 0g
  • Protein: 7.7g
  • Thiamin: 0.69mg 57% DV
  • Magnesium: 165mg 39% DV
  • Selenium: 7.12mcg 19% DV
  • Iron: 2.4mg 13% DV

Flax seeds are a great source of thiamin, a B vitamin that helps convert nutrients into energy. Another stand-out nutrient of flax seed is magnesium, which is important for nerve, muscle, and immune function, per Medline Plus. Meanwhile, selenium protects cells from damage or infection (per the National Institutes of Health, NIH) and iron helps make red blood cells—which carry oxygen through our bloodstream, per Medline Plus.


Some people may be allergic to flax seeds, though it is not common, according to a 2017 study in Medicine.

Flax seeds also contain trace amounts of potential toxins like cyanide. But, as a 2019 research summary published in Nutrients points out, the consumption of flax is highly unlikely to cause cyanide toxicity because levels are very low and the body can detoxify cyanide in amounts as small as those found in flax seeds. Additionally, cooking flax seeds destroys the chemical.

Tips for Consuming Flax Seeds

When shopping for flax seeds, opt for ground flax seeds over whole ones since whole seeds can pass through your intestines undigested, per Medline Plus. This prevents nutrients from being absorbed into the bloodstream.

If whole flax seeds are your only option, no worries, you can grind them yourself with a coffee grinder just before eating.

Just make sure you store your flax seeds in a cool, dark place—like the freezer—since the oil in flax breaks down when exposed to light and air.

Simple ways to eat flax seeds include:

  • Sprinkled on oatmeal or overnight oats
  • Mixed into yogurt
  • Added to pancake batter
  • Used as a garnish for snacks like smoothies, fresh fruit, and avocado toast
  • Folded into nut butter along with oats to make energy balls
  • Baked into cookies, muffins, brownies, and banana bread

You can also use flax seeds as a vegan replacement for eggs in baking recipes. Just mix one tablespoon of ground flax seeds with three tablespoons of water for each egg the recipe calls for.


While small, flax seeds pack a nutritious punch thanks to their ability to reduce blood pressure, improve digestion, and prevent certain types of cancer. They're also quite versatile, as they can be incorporated into both sweet, savory, hot, and cold dishes.

Whether you should consume flax seeds and how often should be based on your own personal preferences and individual health needs. For tailored advice, talk to your healthcare provider or dietitian for tailored guidance.

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