Health Benefits of Flax Seed

The flax plant has given us a wide range of products from bowstrings to boat sails, but the best gift of all may be its tiny seeds. Ancient people in the Middle East and India used flax to make cloth and extracted oil from the seed. Today people still use flax for these purposes, but many people have recognized the benefits of adding flax seed to their diets.  

Flax is a tall plant with slender stems and leaves and an attractive blue flower. When processed, the best flax fibers are creamy white, which is why blonde hair is sometimes called "flaxen." Flax seeds are small and usually brown, yellowish, or tan. The little seeds contain large amounts of nutrients and fiber.

Health Benefits

Flax seed is nutritionally rich, especially in both soluble and insoluble fiber. It is a top source of the omega-3 fatty acid known as alpha-linolenic acid, or ALA. The body turns ALA into DHA and EPA, the same valuable substances found in fish oils. But the real flax seed superstar may be lignans, plant compounds that provide numerous health benefits. Flax seed is the #1 food source of lignans, containing seven times more than the #2 food, sesame seeds.  

Mainly due to these ingredients, flax seed provides many health benefits, including these:

Gut Health

The insoluble fiber in flax seed adds bulk to the stool, preventing constipation. Studies have also shown that fiber-rich foods help food waste travel through the colon more quickly. When waste stays in the intestine too long, some of the toxins can be reabsorbed into the body. Slow transit of food through the intestine can lead to conditions like diverticulitis and colon cancer.

Lower Cholesterol

A meta-analysis of 28 studies showed that adding flax seed to the diet lowers total cholesterol and LDL cholesterol, the "bad" cholesterol. The results varied according to the parameters of the studies, but animal studies had already shown similar effects. The studies used flax seed or lignans derived from flax seed. Studies using flaxseed oil did not produce the same results.


Stroke Prevention

The ALA in flax seed may be effective in improving cardiovascular health and reducing the risk of stroke. This positive effect has appeared in both animal studies and observational studies of humans. A small amount of flax seed is sufficient to improve health, and adding it to the diet has no major negative effects.

Blood Sugar Control

When people with diabetes add flaxseed to their diets, their blood glucose levels improve, several studies have shown. Researchers believe the improvement is due to the combination of fiber, omega-3s, and lignans in the flax seed. 


Flax seed is high in several vitamins and minerals, including these:

Nutrients per Serving

Flax seed provides these nutrients in a two-tablespoon serving: 

  • Calories: 60
  • Protein: 3 grams
  • Fat: 5 grams
  • Carbohydrates: 4 grams
  • Fiber: 4 grams
  • Sugar: 0 gram

Things to Watch Out For

Although the fiber in flax seed is great for gut health, it can cause gas and bloating. If you haven't been eating a lot of fiber, begin using flax seed by adding a teaspoonful a day to your diet. Increase the amount if you have no intestinal distress. Also, drink extra fluids when you use flax seed because the fiber will absorb water. If you skimp on liquids, you could end up with constipation. 

You should opt for ground flax seed, because whole ones can pass through the digestive system whole. You can buy ground flax seed or grind your own. After grinding, refrigerate the flax seed as they lose their freshness quickly. 

How to Use Flax Seed

It's simple to add flax seed to your diet, since a tablespoon or two packs a nutritional punch. Flax seed retains its nutritional value after baking, so one of the best ways to use them is to add them to baked goods. 

You can use flax seed to make an egg substitute suitable for baking. For a mixture that can substitute for one egg, combine one tablespoon of ground flax with three tablespoons of water. Let the mixture sit for a few minutes until it forms a gel, then add to your batter.

Try these easy ways to boost nutrition with flax seed: 

  • Add flax seed to your oatmeal or other hot or cold cereal 
  • Sprinkle on yogurt
  • Add to a smoothie 
  • Add to pancake batter or to muffins or breads 
  • Stir into hearty soups, chilis, or curries 
  • Add to mustard, mayo, or other sandwich spread
  • Put in your salad dressing 
WebMD Medical Reference Reviewed by Dan Brennan, MD on November 07, 2020



The American Journal of Clinical Nutrition: "Meta-analysis of the effects of flaxseed interventions on blood lipids."

BioMed Research International: "Alpha-Linolenic Acid: An Omega-3 Fatty Acid with Neuroprotective Properties—Ready for Use in the Stroke Clinic?"

Cone Health Medical Group: "From Fuel to Stool: 5 Tips to Speed Up Digestion."

Encyclopedia Britannica: "Flax."

ESHA Research, Inc., Salem, Oregon: "Seeds,  flaxseed, plain, meal, ground."

Journal of Food Science and Technology: "Flax and flaxseed oil: an ancient medicine & modern functional food."

Mayo Clinic: "Does ground flaxseed have more health benefits than whole flaxseed?"

Summit Medical Group: "Benefits of Flaxseed."

World's Healthiest Foods: "Flaxseed."

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