Flaxseed Nutrition Facts and Health Benefits

Flaxseed—also commonly referred to as flax seed or linseed—can be a nutritious addition to your diet. The small golden or brown seeds are high in heart-healthy fiber and fatty acids. They can be eaten whole or used to make flaxseed oil, extracts, flour, and food products like salad dressing. Flaxseed has been promoted as a healthful and sometimes medicinal substance for thousands of years, dating back to Hippocrates.

Flaxseed Nutrition Facts

The following nutrition information is provided by the USDA for 1 tablespoon (10g) of whole flaxseeds.

Carbs

There are two different types of carbohydrates in flaxseed. Most of the carbohydrate in flaxseed is fiber (almost 3 grams in a tablespoon of whole flaxseeds). Fiber not only helps to boost digestive health, but fiber also helps to regulate blood cholesterol and boosts satiety—the feeling of fullness after eating.

The rest of the carbohydrate in flaxseed comes from sugar, but it is a very small amount of naturally occurring sugar. 

The estimated glycemic load of flaxseed is zero. Glycemic load takes into account the serving size of a given food or beverage to estimate its impact on your blood sugar. It is considered to be more helpful than just using the glycemic index for people who are choosing foods based on their effects on blood glucose.

Fat

There are just over 4 grams of fat in a tablespoon of whole flaxseed and slightly less in a tablespoon of ground flaxseed. The fat in flaxseed is primarily polyunsaturated fat, which is considered to a "good" fat. Polyunsaturated fat may boost heart health when you use it to replace less healthy fats (like saturated fat) in your diet.

There are two different kinds of polyunsaturated fatty acids (PUFAs) and flaxseed contains both of them. You'll get 230 milligrams of α-linolenic acid (ALA) omega-3 fatty acids in a tablespoon of flaxseed, and 606 milligrams of linoleic acid or omega-6 fatty acid, making these seeds a good plant-based source of fatty acids.

There is just under 1 gram of monounsaturated fat in a single serving of flaxseed and a very small amount (0.4 grams) of saturated fat.

Protein

Adding flaxseed to a salad or smoothie can help boost your protein intake, but not substantially. Flaxseed's 2 grams of protein per tablespoon is about 4% of your daily target (if you consume a 2,000 calorie-per-day diet).

Vitamins and Minerals

Flaxseed provides important micronutrients. However, because the serving size is usually small, the nutritional boost you get from consuming the seeds will only put a small dent in your total daily vitamin and mineral needs.

For example, based on a 2,000-calorie-per day diet, a serving of flaxseed provides 11% of the daily recommended intake (DRI) of thiamin. Thiamin is a water-soluble B vitamin that is needed by the body to metabolize carbohydrate and branched-chain amino acids. It is also vital for neural function. A tablespoon of flaxseed also contains 2% of the DRI of niacin, vitamin B6, and folate.

In terms of minerals, a tablespoon of flaxseed provides 13% of the DRI for manganese and about 10% for magnesium. Other minerals in flaxseed include phosphorus (7% of RDI), copper (6%), and selenium (4%).

Calories

One serving (1 tablespoon) of flaxseed contains approximately 55 calories.

Health Benefits

Flaxseed and flaxseed oil are widely credited with aiding or even curing several ailments. Many people also believe that flaxseed products can reduce your risk for certain diseases. Science offers some support for these claims, but flaxseeds are not a miracle cure for anything.

For example, flaxseed has been investigated as a treatment for hot flashes, especially during menopause. The seeds contain phytoestrogens, which are similar to the hormone estrogen. However, research reviews have found that there is insufficient evidence to support the use of flaxseed for hot flashes and other symptoms of menopause.

In addition, some arthritis sufferers take flaxseed for pain related to the condition. But again, there is insufficient evidence to believe that the seeds can provide relief.

Flaxseed is also sometimes used to treat acne, psoriasis, stomach upset, ADHD, bladder inflammation, diverticulitis, and eczema. Currently, there is little evidence to support these uses. However, the National Institutes of Health National Center for Complementary and Integrative Medicine is funding research to understand how flaxseed may play a role in treatment for ovarian cancer, cardiovascular disease, metabolic syndrome, diabetes, asthma, and inflammation.

Improves Heart Health

Research shows that flaxseed might be beneficial for the heart in at least two ways: It helps lower blood pressure, and (at least in animals) it may slow the progression of atherosclerosis.

Protects Against Some Cancers

Experiments in both animals and humans show that dietary flaxseed may be associated with a reduced risk for breast cancer and of dying from breast cancer. Studies of flaxseed in other cancers, such as those affecting the prostate, lung, colon, ovary, and liver, have also shown promise.

May Help Improve Blood Sugar Control

There is some (limited) evidence to support including flaxseed in your diet if you are trying to manage prediabetes or type 2 diabetes.

Relieves Constipation

Research shows that flaxseed may be able to help in the treatment of constipation. Flaxseed is high in fiber, which might improve digestion.

May Aid in Weight Loss

Previous studies have found that adding whole flaxseed into your diet could help in weight management and weight loss thanks to its appetite satiating effects.

Allergies

Flaxseed allergy is rare, but a few anaphylactic reactions have been reported in the medical literature. There is also potential cross-reactivity between flaxseed and other allergens, including other seeds and legumes. It's important to talk with your healthcare provider if you suspect an allergy to flaxseed.

Adverse Effects

Unripe flaxseeds may contain potentially toxic compounds. Taking flaxseed is likely safe for most adults in doses of a few tablespoons per day. However, consuming the seeds may be unsafe during pregnancy or breastfeeding.

Additionally, people with bleeding disorders, diabetes, gastrointestinal obstruction, hormone-sensitive cancers, hypertension, high blood pressure, or low blood pressure should speak with their healthcare provider before taking flaxseed. People who are on medication to manage any of those conditions should also exercise caution and speak to their provider before including the seeds in their diet.

Varieties

You may find brown or golden flax seeds in your local grocery store. There is little difference nutritionally between the two varieties, but golden flaxseed has a nuttier taste. You can find whole flaxseeds, ground seeds, flax meal (flour), flaxseed oil, or supplements in the form of tablets, extracts, and capsules. Flax is also an ingredient in many packaged snacks such as crackers, chips, and cookies.

When It's Best

Flaxseed is available in your grocery store year-round.

Storage and Food Safety

Store whole flaxseeds in an airtight container in your pantry or in a dark, cool cupboard. Properly stored, they should last up to 12 months. Flaxseed (ground or whole) can be frozen to extend its shelf life. Flaxseed oil should be stored in a cool, dark cupboard away from heat sources (such as an oven). If your flaxseeds or flaxseed oil becomes rancid, discard it.

How to Prepare

Some people prefer to grind flaxseed to make it easier to add to drinks and recipes. Grinding doesn't make flaxseeds healthier. But if you choose to grind your own at home (or at your local market), you have the benefit of knowing your ground flaxseed contains only flaxseed and no fillers or other ingredients.

Flaxseeds are easy to toss into a cup of yogurt to provide a crunchy texture and boost of nutrition. They are also easy to put in a smoothie. However, the seeds will add thickness to the beverage and can produce a gel-like consistency if you don't drink it right away.