Power Foods - Lignan Flax Oil & Cancer Risks There's a good reason that we recommend flax seed oil, especially lignan flax oil, perhaps the richest source of valuable lignans on earth today. You might be asking, "What on earth lignans are." Lignans happen to be one of the most important foods people can consume on a daily basis to support normal cell multiplication and reduce cancer risk. Interestingly, a lignan-rich diet can minimize cancer spread (metastasis). Not all flax oils are good sources of lignans due to filtration methods. The best lignan flax oil is non-filtered and unrefined and, thus, a rich source of flax particulates which are high in lignans. Lignans: Health Saviors Since the early 1980's, these plant compounds with estrogen-like qualities have come under increasing scientific scrutiny after studies suggested they may interfere with the development of breast, prostate, colon, and other cancers. Indeed, with cancer now striking greater than one in three Americans, perhaps lignan's greatest gift to humankind is their well-documented, anti-cancer activity. This should not be construed as a cancer cure. Flax isn't that. But, clearly, flax should be part of a healthy diet that supports normal cell development and growth and minimizes carcinogenic influences on cellular activities. Scientific/Medical Evidence Flax is among the richest sources of lignans in the diet today. Scientific evidence shows how important it is to consume a lignan-rich diet. Use of flax as a cancer prophylactic is "an area that I think has a lot of promise," notes Lilian U. Thompson, Ph.D., of the University of Toronto, one of a handful of researchers investigating the relationship between flax and cancer inhibition.  Thompson and her colleagues began their scientific quest into the
powers of lignans by seeking the richest source of lignan precursors,
screening for the production of two marker lignans, enterolactone and
enterodiol, from about 70 common foods. Finding that flaxseed
produced 75 to 800 times more of these substances than any other foods
led them to their intensive study of flax. Today, Thompson is one of
the world's leading authorities on flax's human health benefits.
Dr. Thompson knew that flaxseed lignans had been shown to be protective at the early promotional stage, when cancers have not quite formed. In an experimental study, she wanted to determine whether supplementation with flaxseed, it's lignan or oil fractions, beginning 13 weeks after carcinogen administration, would reduce the size of already established mammary tumors present at the start of treatment, as well as appearance of new tumors. After seven weeks of treatment, established tumor volume was over 50 percent smaller in all treatment groups while there was no change in the placebo group. The correlation between established tumor volume and urinary lignan excretion "indicates that the reduction in tumor size is due in part to the lignans derived from... flaxseed." Meanwhile, researchers from the Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, Nebraska, investigated the effect of dietary supplementation of flaxseed, the richest source of lignans, on experimental melanoma cells. Flax reduced tumor occurrence by up to 63 percent. The addition of flaxseed to the diet also caused a dose-dependent decrease in tumor area and volume, implying that it could be beneficial both in prevention and treatment. "These results provide the first experimental evidence that flaxseed reduces metastasis and inhibits the growth of the metastatic secondary tumors in animals. It is concluded that flaxseed may be a useful nutritional adjuvant to prevent metastasis in cancer patients." Next, Thompson participated in a study to determine whether flax's lignans might have a beneficial anti-estrogenic effect much like the drug tamoxifen but without its risks. A woman's cumulative exposure to estrogen, including the length of her estrous cycle, plays an important role in her lifetime breast cancer risk; the more estrogen to which her tissues are exposed, the greater her risk. Thus, the anti-estrogenic effects of flaxseed were compared with tamoxifen by monitoring estrous cycles. Four-week supplementation of a high-fat diet with flaxseed produced a dose-related cessation or lengthening of the cycle in about two-thirds of animals. With tamoxifen, 83 percent of the animals had irregular cycles. Thus, both compounds were antiestrogenic; however, flax performed its activities without gross tissue toxicity (including uterine cancer risks). Most recently, Thompson and other researchers from the Department of Nutritional Sciences, University of Toronto, Ontario, Canada, found that lignans significantly reduced the proliferation of four different types of human colon tumor cell lines, even if they were incubated with various levels of estrogen cancer promoters. Comparative research also suggests an anti-cancer role for lignans. Researchers from the Department of Biological Sciences, Clark Atlanta University, Georgia, compared levels of urinary lignans among cancer-resistant primates with those of humans. It was found that primates consuming their regular food excreted large amounts of the lignans, enterolactone and enterodiol. When fed a high fat diet, excretion levels were reduced by more than 90 percent to a level observed in women with breast cancer. "These results suggest that diet profoundly influences the excretion of both animal lignans... in urine," the researchers concluded. "Because non-human primates are particularly resistant to mammary and genital carcinoma on estrogen treatment, the present data suggest that the very high levels of phytoestrogens and lignans, as found during exposure to the regular diet, may partially account for why these primates are so resistant to hormonal manipulations to induce cancer." We also have increasingly important human evidence, this from the University Department of Surgery, Queen Elizabeth II Medical Centre, Perth, Western Australia. In this case-control study, published in Lancet, women with newly diagnosed early breast cancer were interviewed by means of questionnaires, and a 72 hour urine collection and blood sample were taken. The urine samples were assayed for various plant constituents including the lignans enterodiol, enterolactone, and matairesinol. After adjustment for age at menarche, parity, alcohol intake, and total fat intake, high excretion of both equol (a plant estrogen) and enterolactone was associated with a "substantial reduction in breast-cancer risk.," note the researchers. "There is a substantial reduction in breast-cancer risk among women with a high intake (as measured by excretion) of phyto-estrogens, particularly the isoflavonic phyto-estrogen equol and the lignan enterolactone. These findings could be important in the prevention of breast cancer." Meanwhile, researchers from the University of Wales College of Medicine, Cardiff, United Kingdom, determined the concentrations of lignans in prostate fluid from Portuguese, Chinese and British men. The mean concentrations of enterolactone and other plant estrogens were very high among Portuguese and Asian men, respectively.* The high levels of lignans and related plant estrogens may, in part, be responsible for lower incidences of prostate cancer in men from Mediterranean and Asian countries, the research team concluded. Personal Counsel It is important that people overcome their fear of fat. Saturated fats found in beef and dairy, trans-fatty acids from hydrogenated oils used in baked goods, candy and other snacks, and the types of omega-6 fatty acids in corn oil are "bad" fats that cause heart disease and promote cancer. We get way too much of these fats in our diet. Flax, on the other hand, with it's omega-3 fatty acid and lignans, is a good fat. The key is to start consuming more of the good fats. Of course, much more research is required before we can say with absolute confidence that flax prevents cancer or should be used in its treatment. All we can responsibly tell you for now is that many reasons can be found to put flax in your diet since flax is an all-around healthy food that supplies omega-3 fatty acids, a type of fat usually lacking in the modern American diet. Flax is especially for supporting normal cell functions. How to Find the Best Lignan Flax Oil The choice of a flax oil product is also critical since the quality of the oil determines its taste, antioxidant powers and, of course, lignan content. Be sure the company that produces your flax is M.A.D. about fresh lignan flax oil. Here's what to look for when it comes to being MAD about fresh flax:  This service is called Fresh ExPress and it guarantees you the absolute freshest flax oil anywhere. You will find this type of extremely high-quality, lignan flax oil in the refrigerator sections of natural health centers nationwide. References: 1. footnote* Thompson, L.U., et al. "Flaxseed and its lignan and oil components reduce mammary tumor growth at a late stage of carcinogenesis." Carcinogenesis, 1996; 17(6):1373-6. 2. Yan, L., et al. "Dietary flaxseed supplementation and experimental metastasis of melanoma cells in mice." Cancer Lett, 1998; 124(2):181-6. 3. Orcheson, L.J., et al. "Flaxseed and its mammalian lignan precursor cause a lengthening or cessation of estrous cycling in rats." Cancer Lett, 1998; 125(1-2):69- 76. 4. Sung, M.K., et al. "Mammalian lignans inhibit the growth of estrogen-independent human colon tumor cells." Anticancer Res, 199; 18(3A): 1405-8. 5. Musey, P.I., et al. "Effect of diet on lignans ad isoflavonoid phytoestrogens in chimpanzees." Life Sci, 1995; 57(7):655-64.6. Ingram, D., et al. "Case-control study of phyto-oestrogens and breast cancer [see comments]." Lancet, 1997; 350(9083):990 6. Ingram, D., et al. "Case-control study of phyto-oestrogens and breast cancer [see comments]." Lancet, 1997; 350(9083):990-4. |