Flax Essence Special
by Dallas Clouatre, Ph.D.
Flaxseed was consumed by the ancient Babylonians more than 5,000 years ago and was prized by the Greeks and Romans for its health-promoting benefits. The seeds supply both essential fatty acids and fiber, much of it soluble like that found in fruit and oat bran. Recent research has brought to light yet more benefits from components contained within flaxseed fiber known as lignans. Jarrow Formulas makes the benefits of flax lignans available in concentrated form.
Approximately 41 percent of flaxseed consists of oil (fatty acids), of which approximately 70 percent is polyunsaturated. There is a high ratio of alpha-linolenic acid (an omega-3 fatty acid) to linoleic acid (an omega-6 fatty acid). More than half the fat in flaxseed is of the omega-3 fatty acid type, which is the component that most people associate with flax. Omega-3 fatty acids are now widely accepted as protecting against coronary heart disease, stroke, hypertension, inflammation, autoimmune disorders and a number of cancers.
What Are Flax Lignans?
Lignans are a group of fiber-like moleculesthat are found in plants, especially the seeds. Lignans should not be confused with lignin, which is an insoluble fiber that is structurally related. Indeed, in the plant world, lignans might be said to be the building blocks for lignins. Lignans are especially abundant in flaxseed, with some authorities estimating that flax contains up to 800 times as much of these items as do other food sources. Flax lignans form fibrous chains that effectively bind toxins found in the gastrointestinal tract.
However, flax lignans are far more than just fiber. Lignans are phytoestrogens, that is, plant compounds which weakly resemble estrogens, the female sex hormones produced in the human body in both women and men. Other such phytoestrogenic compounds include isoflavones, coumestans, flavonoids and phytosterols. Phytoestrogens can compete for receptor sites with the body’s own estrogen when estrogen levels are high or supplement estrogenic activity when estrogen levels are low. Just as significantly, they complete with what are known as xenoestrogens. Xenoestrogens are harmful estrogen-like molecules from the environment, such as are found in pesticides, solvents, adhesives, soap emulsifiers, plastics, PCB’s, etc. One reason that eating fruits, vegetables and legumes promotes health and reduces the risk of cancer is that phytoestrogens found in these foods help to protect us from toxins that we have added to the environment.
Flax is particularly rich in the lignan secoisolariciresinol diglycoside (SDG), and it also contains small amounts of the lignans matairesinol, pinoresinol and isolariciresinol. Bacteria in the digestive tract act on some of these lignans and convert them into yet more potent substances. The lignans SDG, matairesinol and pinoresinol in flax, are converted in the colon of humans and other animals to the mammalian lignans enterodiol and enterolactone. Enterodiol and enterolactone are called mammalian lignans because they are produced by bacteria in the mammalian colon, but are not found in plants. After a circuitous route through the body, these flax lignan metabolites are removed by the kidneys.
The Benefits of Lignans
Although flax lignans are not as powerful as the body’s own estrogens, they can still exert important effects. In general, flax lignans are balancing to estrogen metabolism. If the level of estrogens in the blood is high, such as in some women who suffer from premenstrual syndrome, then lignans will tend to reduce the body’s response. If the level of estrogens in the blood is low, such as in women after menopause, then lignans will tend to increase the body’s response. Hence, lignans can act either as phytoestrogens (weak estrogens) or as antiestrogens, depending on the circumstances. The major benefits of flax lignans that have been researched thus far are in these areas: protection against breast, prostate and colon cancers; improvements in cardiovascular health; reduction in menopause symptoms; antioxidant protection; and support for bone health. At this point in time, more than 100 research studies have been published on flax lignans.
Flax lignans stimulate the production by the liver of sex hormone-binding globulin (SHBG). This increases the clearance of sex hormones from the body and may have other effects. By displacing estrogen being carried by SHBG, lignans can reduce the level of estrogen carried to the tissues. Lignans, furthermore, decrease the activity of an enzyme known as estrogen synthetase (aromatase), which can increase estrogen production undesirably from fat cells and other sources in men, as well as women. Animal studies and human population studies support the protective role of lignans against hormone-sensitive cancers. As of yet, however, clinical trials testing only purified lignans remain rare and much information must be extrapolated from studies using flaxseed or reduced-oil flaxseed.
There may be other mechanisms at work than the antiestrogenic factor. Lignans seem to reduce the incidence of colon cancer, which is not hormone-sensitive. Research with patients with prostate and other cancers has shown that there is a dramatic lowering of the lignan content in the body wastes compared with non-cancerous individuals. This suggests that lignan compounds may help boost immune response and the detoxification of the by-products of metabolic processes. Research also suggests that flax and its lignans may decrease angiogenesis (the growth of blood vessels that supply oxygen and nutrients to tumors for growth). Furthermore, flax lignans possess antioxidant properties and in animal trials have been found to lower cholesterol and to protect against induced atherosclerosis.
Women may have the most to gain in terms of total health benefits. Because lignans are phytoestrogens, under conditions of low blood estrogen levels, such as menopause, lignans can weakly activate estrogen receptors. This action is similar to that found with isoflavones from various legumes. Flaxseed consumption (40 grams per day for four months) in one study was as effective as hormone replacement therapy in reducing menopause symptoms among 25 menopausal women. Conversely, an antiestrogenic effect (and perhaps an improved rate of estrogen clearance) would seem to have been demonstrated in a trial with premenopausal women taking flax seed who exhibited reduced breast pain and tenderness during the menstrual period.
Men, too, can benefit. At least one pilot clinical trial can be found in the medical literature regarding a reduction in markers of prostate cancer, and recent epidemiological studies link lignan consumption with a reduction in cardiovascular risk factors. Interestingly, flax consumption does not appear to affect testosterone levels in men and, as noted already, flax lignans inhibit that activity of the aromatase enzyme that increases estrogen production.
Other potential benefits include improvements in bone health and kidney function. There even is evidence that suggests that lignans may help to protect against hair loss and acne.
Safety
Ten grams of flax provides approximated 20 milligrams of secoisolariciresinol, the active fraction of the primary flax lignan secoisolariciresinol diglycoside (SDG). Research studies with ground flaxseed at dosages from 5 to 50 grams per day thus supplied 10 to 350 milligrams of secoisolariciresinol without incident, which indicates the inherent safety of flax and its lignans. The only group which perhaps should not supplement with large amounts of flaxseed or its lignans (flax oil is OK) is pregnant women or those looking to conceive. No harm has ever been found, but simple prudence suggests caution in taking any type of supplement during pregnancy.
Jarrow Formulas supplies flax lignans as a specially concentrated lignan extract via capsule, softgel and other deliveries. When supplementing with this concentrated source of secoisolariciresinol diglycoside (SDG), look to increase intake by 40 milligrams or more SDG per day.
Dallas Clouatre, Ph.D., is a Jarrow Formulas consultant based in Santa Monica, California. He is a prominent industry consultant in the US, Europe, and Asia, and is a sought-after speaker and spokesperson. He earned his A.B. from Stanford and his Ph.D. in European Intellectual History from the University of California at Berkeley. A member of the American College of Nutrition, he is a regular contributor to various industry publications. He is the author of numerous books, including FAQ: All about Grapeseed Extract, SAM-e: The Ultimate Methyl Donor, Anti-Fat Nutrients (3rd edition), and The Prostrate Cancer Miracle.
