Health Benefits of Flax Seeds

A serving of flax seeds provides impressive amounts of nutrients and benefits 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.

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

Benefits

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. An 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 study 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.

Support Digestive Health

Four tablespoons of flax seeds provide 27% of the daily recommended intake of fiber—a key nutrient for digestive health. The benefits of fiber include:

  • Making you feel full faster
  • Helping to manage weight
  • Prevents constipation

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. 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 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

A study 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 meta-analysis 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.

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.

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

Nutrition

Flax seeds may be tiny, but they're chock full of nutrients. 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. Meanwhile, selenium protects cells from damage or infection. And iron helps make red blood cells—which carry oxygen through our bloodstream.

Risks

Some people may be allergic to flax seeds, though it is not common.

Flax seeds also contain trace amounts of potential toxins like cyanide. But, 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. 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.

A Quick Review

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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Sources
Health.com uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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