Flax Lignans, Omega 3 & your Health

Flaxseed Oil is now well recognized as the richest source of Omega 3 essential fatty acid. However Flaxseed hold another well kept secret. Flaxseed contains very high levels of a unique plant Phytoestrogen called Lignan. When flaxseed is pressed to produce flaxseed oil the lignan component remains in the flaxmeal. So to get the benefit of flax lignans you must consume flax meal or tablets containing flax lignans.

Flaxseed has become popular as a rich source of both soluble and insoluble fibre, Protein and of course the omega 3 essential fatty acid alpha linolenic acid (ALA). The body further metabolises ALA into the other essential fatty acids Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA) better known as the fish oil essential fatty acids.

Lignans

There is another important component of flaxseed that is gaining much attention. Flaxseed contains the richest known source of lignans, some 70-800 times more lignans than most other sources. Flax lignans are being studied for their potential benefits in both men’s and women’s health. As this work continues the scientific community continues to uncover new and exciting news about lignans.

What are Lignans?

Lignans are phytoestrogens or naturally occurring plant estrogens that can have a balancing effect on hormones. Lignans also exhibit strong anti-oxidant effects. The main lignan in flaxseed is secoisolariciresinol dyglucoside, or more simply SDG. The most interesting thing about flax lignans is when they are eaten, SDG is converted by bacteria in the colon to mammalian lignans enterolactone and enterodiol. This is important as it is these mammalian lignans that exert health effects in the body.

Research indicates that flaxseed lignans may be protective of men against prostate conditions and in womens health they are being studied for their protective effects against breast cancer and for reducing the symptoms of menopause. Other conditions where flaxseed lignans may have beneficial effects include heart health, colon cancer, hair loss, acne and inflammation.

Womens Health

Management of estrogen levels with plant phytoestrogens has been a topic of research for a number of years. Isoflavonoids and lignans are two commonly occurring phytoestrogens. Isoflavonoids occur principally in soy whilst lignans occur in most plants. The richest source is in flaxseed (Linum usitatissimum), also known as Linseed, with 70-800 times more lignans than any other plant.

The protective effect of flaxseed lignans on breast tissue may be due to their role in lowering circulating levels of free estrogen. Estrogens mainly circulate as inactive conjugates with sex hormone binding globulin (SHBG). Supplementation with lignans has been shown to increase levels of SHBG. Estrogen is further metabolized to by different pathways to two different bio-markers. One metabolite is 16 alpha-hydroxyestrone which is known to be genotoxic. The other is 2 hydroxyestrone which is proposed to exert protective effects for breast tissue. Flaxseed lignans promote the formation of the later thereby providing protection to breast tissue. Flaxseed lignans may also lower free estrogen by inhibiting aromatase enzymes and stimulateing P450 enzymes.

Mens Health

Flaxseed lignans can also play a role in male health and especially the health of the prostate gland. In the body testosterone is converted to a more potent form called dihydrotestosterone (DHT). Normal, healthy prostate cells require DHT for growth. However too much may cause abnormal growth, leading to an enlarged prostate or Benign prostatic hyperplasia (BPH) or causing prostate cancer cells to divide. Like estrogen, most testosterone is bound to SHBG. As flax lignans increase SHBG there should be less testosterone to stimulate prostate growth. Flax Lignans have also been shown to inhibit the action of an enzyme, 5 alpha reductase, that is responsible for the conversion of testosterone to the more potent DHT. Further research is underway on these promising actions of flaxseed lignans.

By Warren Morey, Naturopath