Flaxseeds (also called linseeds) are a rich source of micronutrients, dietary fiber, manganese, vitamin B1, and the essential fatty acid alpha-linolenic acid, also known as ALA or omega-3.
The seeds come from flax, one of the the oldest fiber crops in the world – known to have been cultivated in ancient Egypt and China.
It is not only a source of healthy fat, antioxidants, and fiber; modern research has found evidence to suggest that flaxseed can also help lower the risk of diabetes, cancer, and heart disease.
King Charlemagne of the 8th century believed so strongly in the health benefits of flaxseed that he demanded his loyal subjects eat the seeds and passed laws to make sure of it.
The Latin name for flax is Linum usitatissimum, which means “the most useful.
This MNT Knowledge Center feature is part of a collection of articles on the health benefits of popular foods. It contains a nutritional profile on flaxseed, numerous health benefits associated with its consumption, as well as side effects.
To reap the most benefits from flaxseeds, they should be bought in ground form or ground before consumption, as whole flaxseeds can sometimes pass through the digestive tract undigested.
Nutritional profile for Flaxseed
There are two main types of flaxseed: golden flaxseed and brown flaxseed. Their nutritional profiles are very similar and both contain the same number of short-chain omega-3 fatty acids.
The American Nutrition Association highlighted the importance of this “neglected food”, stating that flaxseed is not only “an excellent source of two fatty acids that are essential for human health – linoleic acid and alpha-linolenic acid,” but also “an excellent source of fiber and a good source of minerals and vitamins.”1
Flaxseed is very low in Cholesterol and Sodium
Nutritional value of Flaxseed per 20 g (2 tbps)
|Energy – 54.7 kcal (DV = 3%)||Carbohydrates – 3.0 g (DV = 1%)|
|Sugars – 0.2 g||Dietary fiber – 2.8 g (DV = 11%)|
|Fat – 4.3 g (DV = 7%)||Saturated fat – 0.4 g (DV = 2%)|
|Monounsaturated fat – 0.8 g||Polyunsaturated fat – 2.9 g|
|Protein – 1.9 g (DV = 4%)||Thiamine (vit B1) – 0.2mg (DV = 11%)|
|Riboflavin 0.0mg||Niacin (vit. B3) – 0.3mg (DV = 2%)|
|Pantothenic acid (B5) – 0.1mg (DV = 1%)||Vitamin B6 – 0.0 mg|
|Folate – 8.9 mcg (DV = 2%)||Vitamin C – 0.1 mg (DV = 0%)|
|Calcium – 26.1mg (DV = 3%)||Iron – 0.6mg (DV = 3%)|
|Magnesium – 40.2 mg (DV = 10%)||Phosphorus – 65.8mg (DV = 7%)|
|Potassium – 83.3 mg (DV = 2%)||Zinc – 0.4mg (DV = 3%)|
Source: USDA Nutrient Database
Flaxseeds are rich in:
- Lignans – lignans are one of the major classes of phytoestrogens. They are estrogen-like chemical compounds with antioxidant qualities, able to scavenge free radicals in the body. Flaxseed is considered to be one of the best sources of lignans (0.3 g per 100g). A study, published in the journal Critical Reviews in Clinical Laboratory Sciences, concluded that “lignan-rich diets may be beneficial, particularly if consumed for life.”2
- Fiber – flaxseed is rich in both soluble fiber (which dissolves in water) and insoluble fiber (which does not dissolve in water). According to Mayo Clinic3, “soluble fiber dissolves with water and creates a gel-like substance that helps to lower blood cholesterol and glucose levels.” Whereas insoluble fiber “absorbs water which adds bulk to your digestive tract and helps to move things through quickly.”
- Omega-3 fatty acids – these are considered to be “good fats” that are beneficial for the heart. These essential acids are only obtainable by eating the right foods; the human body is not able to produce them.
Health benefits of Flaxseed
The therapeutic and beneficial properties of consuming flaxseed are not yet completely understood, and many claims still lack “high-quality” studies to back them up.
However, emerging research suggests that flaxseed might indeed be the wonder food many people claim it to be.
The health benefits associated with flaxseed include:
- Protecting against cancer – consuming flaxseed may help protect against prostate, colon, and breast cancers. Flaxseed is thought to prevent the growth of cancerous cells because its omega-3 fatty acids disrupt malignant cells from clinging onto other body cells. In addition, the lignans in flaxseed have antiangiogenic properties – they stop tumors from forming new blood vessels.One U.S. study presented at the 43rd annual meeting of the American Society of Clinical Oncology (ASCO) revealed that consuming flaxseed can stop prostate cancer tumors from growing. Dr Wendy Demark-Wahnefried, lead investigator of the study said that the team were “excited that this study showed that flaxseed is safe and associated with a protective effect on prostate cancer“.
- Lowering cholesterol – researchers at the Iowa State University’s Nutrition and Wellness Research Center found that cholesterol levels lowered among men who included flaxseed in their diet. Suzanne Hendrich, lead author of the study, said that for “people who can’t take something like Lipitor, this could at least give you some of that cholesterol-lowering benefit.”
- Preventing hot flashes – a study published in the Journal of the Society for Integrative Oncology suggests that dietary intake of flaxseed can decrease the risk of hot flashes among postmenopausal women. “Not only does flaxseed seem to alleviate hot flashes, but it appears to have overall health and psychological benefits as well,” concluded Dr. Pruthi.
- Improving blood sugar – there is strong evidence to suggest that consuming flaxseed everyday improves glycemic control in obese men and women with pre-diabetes4, according to a study published in Nutrition Research.
- Protecting against radiation – a diet of flaxseed may protect skin tissue from being damaged by radiation, revealed researchers at the Perelman School of Medicine at the University of Pennsylvania. The investigators concluded that their “study demonstrates that dietary flaxseed, already known for its strong antioxidant and anti-inflammatory properties, works as both a mitigator and protector against radiation pneumonopathy.”
Side effects and precautions
Even though research on the safety of taking flaxseed during pregnancy is scarce, pregnant women should stay on the safe side and avoid consuming flaxseed because of its estrogen-like properties which doctors believe may affect pregnancy outcome. In addition, people suffering from a bowel obstruction should avoid flaxseed too (because of its high level of fiber), according to the University of Maryland Medical Center.5
Side effects associated with the consumption of flaxseed, include: