There’s nothing more beautiful on the prairie landscape than a field of flax, blooming in deep blue next to golden yellow canola. In Canada most commercial flax production involves varieties of seed that are crushed and used to produce different grades of oil, both for culinary and non-food purposes (e.g. linseed oil for paints and wood finishes). In Europe flax is raised for fibre that is spun into linen, an industry that is several thousands of years old. However, in recent years, alongside these markets is an increasing consumer demand for flax as a food, and the research that has been done (it is ongoing) has revealed that the seeds, indeed, have several health benefits.
Flax contains a variety of nutrients which it holds in common with other seeds, but it appears flaxseeds offer a number of unique health benefits due to the high content of three components – omega-3 fatty acid, fibre-like compounds known as lignans and mucilage, a water-soluble fibre. It is thought that all three in combination play a key role in providing significant benefits.
One of these benefits is health of the cardiovascular system which merits examination. The primary omega-3 fatty acid in flaxseed is alpha-linoleic acid (ALA) which helps protect blood vessels from inflammatory damage. Similar protection is provided by lignans which inhibit the formation of platelet activating factor, and also provide antioxidant benefits by reducing oxidative stress on blood vessels.
Regulate blood pressure
It must be understood that research on the effect that ingesting flaxseed has on blood pressure is limited, but a few studies have shown a decrease in LDL cholesterol (the “bad” cholesterol) after eating seeds – this would improve the ratio of HDL (the “good” cholesterol) to LDL. General research points out that increased intake of omega-3 fatty acids (which flaxseed contains in significant amounts) helps regulate blood pressure.
In addition to providing antioxidant benefits, lignans have the ability to act as phytoestrogens – in other words, lignans are one of few naturally occurring compounds that can function as weak or moderate estrogen when consumed by humans. While this whole area is complex, it does appear that the presence of lignans in flaxseed may help in the management of perimenopausal and postmenopausal symptoms (including hot flashes, insomnia and mood swings) as well as during hormone replacement therapy (assisting in strengthening bone, thus reducing the risk of osteoporosis).
While fibre is sometimes overlooked as a key component in optimum health, foods high in fibre such as flaxseeds are imperative for proper digestive function. The mucilage in flaxseed refers to water-soluble gel-forming fibre that helps prevent too rapid emptying of the stomach contents into the small intestine, thereby improving absorption of nutrients. Insoluble fibre also present in flaxseed stimulates the colon which increases peristaltic contraction to move waste products out of the body.
Oxidative stress
Certainly other health benefits flow from these specific features of flaxseed – for example, the fact that the seed contains antioxidant and anti-inflammatory properties indicates it might also help prevent cancer – particularly breast, colon and prostate cancers. Remember that oxidative stress and chronic inflammation are risk factors for a wide variety of problems which lead to type-2 diabetes, asthma, obesity and metabolic syndrome.
The question is: how much flaxseed should one ingest, and in what form? The usual rule of “all things in moderation” applies here – thus two tablespoons of flaxseed is generally considered as one serving, and this quantity once a day or several times a week is adequate. The ground seed – easier for your body to digest than whole seed – can be sprinkled on cold or hot breakfast cereal, added to muffin or cookie batter, or thrown into smoothies. Whole seed may be used to provide texture to breads and cereals. Both forms of flaxseed should be stored in the refrigerator since the seed is high in oil and thus prone to rancidity.
