BREAST CANCER; MAKING THE CASE FOR LIGNAN FLAXSEED OIL.
The American Cancer Society reports that one in eight women will contract breast cancer. Unfortunately, breast cancer may be present for as long as four years before it can be detected by mammography or self-examination. Further, many women are under the misconception that if they do not have a family history of breast cancer, they need not be concerned. The truth is the majority of women today who are diagnosed with breast cancer show no family predisposition. The above facts call for every woman to implement a proactive approach to prevent the disease.
We suggest that every woman take at least one tablespoon of lignan-rich flaxseed oil daily to reduce her risk of breast cancer and minimize the potential for it to spread, should it occur.
Lignan-rich flaxseed oil is unique. Unlike regular flaxseed oil, the lignan-rich flax particulate from flaxseeds is retained in the oil, delivering powerful cancer fighting lignan precursors. There may not be a single nutritional supplement or pharmacological drug today that can offer the same level of protection against cancer and other diseases as delivered with the combination of flaxseed oil and lignan precursors.
Making the Case for Flaxseed Lignans
Beginning in the 1980’s consumers were advised by the Surgeon General and the National Academy of Sciences that diets low in saturated fat and high in fiber could be beneficial to their health. This advice was driven by new health statistics that showed that five of the ten leading causes of death in the United States including coronary heart disease, some types of cancer, stroke, certain types of diabetes and atherosclerosis were related to dietary imbalances.
This new information convinced the National Cancer Institute (NCI) to undertake a $20.5 million program to learn more about natural plant chemicals (phytochemicals) in certain food groups that may prevent cancer.
One of the first and most promising foods to be studied was flaxseed. It had been previously discovered that flaxseed contained phytochemicals known as lignans within the cell matrix of its seed. Much of the interest surrounding plant lignans is based on the suspected association between them and the low incidence of breast and colon cancers of those consuming a plant and grain based vegetarian diet. In other words, people who are shown to have high levels of lignans present in their blood, urine and feces have the lowest rates of several malignant diseases.
FACT: Flaxseed, in particular, contains 100 to 800 times more plant lignans than its closest competitors, wheat bran, rye, buckwheat, millet, soy beans and oats.
Once consumed, lignans found in flaxseed are converted to mammalian lignans. These mammalian lignans bind with estrogen receptors, where studies suggest they may induce the production of a special sex hormone binding compound. This compound, known as sex hormone binding globulin (SHBG), regulates estrogen levels by removing excess estrogen from the body. Lignans are thought to be estrogen modulators, helping to balance estrogen activity within the body. These and other positive findings were presented by both the Food and Drug Administration and the NCI as well as several research institutions at the recent annual convention on Experimental Biology held in New Orleans, Louisiana.
Make no mistake. Flax oil is a fat. But it is a good fat. For example, the much-touted Mediterranean diet, traditionally consumed in Greece and regions of Italy, emphasizes whole grains, fruits, vegetables, seafood, and olive and walnut oil with limited meat and dairy. It is not a particularly low-fat diet, however. In fact, the average daily intake of overall fat for Greek women is forty percent of total calories, a figure roughly equivalent to the American diet. Yet, Greek women have much lower breast cancer rates than their American counterparts. Together with a higher intake of vegetables, whole grains and fruits, a high intake of neutral or beneficial fats found in olive and walnut oil appears to be protective, observes researcher Emanuela Taioli.
Meanwhile, Israel has one of the highest intakes of polyunsaturated and saturated fats in the world. The consumption of omega-6 polyunsaturated fatty acids, which are found in safflower, corn and other highly processed commercial cooking oils, is about eight percent higher than in the United States and 10 to 12 percent higher than in most European countries. Not surprisingly, there is an extremely high prevalence of cardiovascular diseases, hypertension, non-insulin-dependent diabetes mellitus and obesity among Israeli Jews. There is also an increased cancer incidence and mortality rate, especially in women, compared with western countries. Studies suggest that high omega-6 fatty acid consumption might be the cause.
Pioneering Cancer Research
“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 is one of the worlds leading authorities on flax’s human health benefits, especially in the area of its use as part of cancer prevention and treatment. In one of her early studies, Thompson learned flaxseed lignans had been shown to be protective at the early promotional stage when cancers have not quite formed. She then wanted to determine whether supplementation with flaxseed, 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. This study demonstrated that reduction in tumor size was due in part to the lignans derived from flaxseed.
In a 1999 report in Carcinogenesis, Thompson and a co-investigator presented intriguing experimental evidence that suggests starting our daughters out on lignan-rich flaxseed oil early on in their lives (including consumption by the mother during pregnancy)can reduce their lifetime breast cancer risk. Flax lignans appear to do so by affecting the highly proliferative terminal end bud structures in the developing mammary gland. Stimulating the terminal ends to develop into alveolar buds and lobules has been suggested to be protective against mammary cancer. In this experimental study, early consumption of flax also delayed onset of puberty.
The Lignan Connection
In a case-control study from the Queen Elizabeth II Medical Center, Perth, Western Australia, 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 lignans. It was determined that there is a substantial reduction in breast-cancer risk among women with a high intake of phyto-oestrogens, particularly the isoflavonic phyto-oestrogen equol and the lignan enterolactone.
Similarly, in a study published in the British Journal of Cancer researchers state there is convincing evidence that low levels of various fatty acids in adipose breast tissue and the emergence of aggressive metastases are intimately related. 121 women patients with an initially localized breast cancer were studied. Their adipose breast tissue was obtained at the time of initial surgery and it’s fatty acid content analyzed. A low level of alpha-linolenic acid (found predominantly in flax) was strongly associated with the presence of vascular invasion, indicating the cancer was likely to spread. After an average 31 months of follow-up, 21 patients developed metastases. Large tumor size, high cell-division rates, presence of vascular invasion and low levels of alpha-linolenic acid were single factors significantly associated with an increased risk of metastasis. (note: alpha-linolenic acid can be considered as a marker for lignan intake.)
The Antiestrogen Effect
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. Because flax lignans are weakly estrogenic, it has been thought that they might displace on the receptors of breast cells more toxic forms of estrogen that are likely to increase women’s risk of cancer. Thompson participated in another study to determine whether flax’s lignans might have a beneficial antiestrogenic effect, much like the drug Tamoxifen but without its risks.
The antiestrogenic 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 Tamoxifen’s gross tissue toxicity (including uterine cancer risks).
To appreciate the dual protective effect of lignans and flaxseed oil, it is imperative that consumers recognize and purchase the right products. Look for flaxseed oil products that are labeled as high-lignan. Flaxseed oil should be gently expeller pressed without filtration or refinement.
Resource: LIGNAN FLAX OIL