Nutritional Ingredients for Breast Health

References

Breast cancer is both terrifying and urgent. Like childbirth or menopause, breast cancer is an initiation where one’s former self dies and a new self emerges. It’s an epidemic—one that can’t be limited to personal transformation, no matter how profound for the individual, no matter how much difference that one person can make to the whole. Instead, the larger, meta-story reveals the power of breast cancer.

The body’s cells usually grow and rest in cycles, which are controlled by genes. When the genes are in good working order, they maintain healthy and controlled growth. When genes develop an abnormality, they sometimes lose their ability to control the cycle of cell growth and rest.

Breast cancer is an uncontrolled growth of breast cells. It’s a malignant (cancerous) tumor that starts from cells of the breast. The disease occurs mostly in women, but men are also susceptible.

One of the causes of cells becoming abnormal and reproducing wildly is damage to the DNA, the “brain” of the cell. This damage causes mutations and activation of oncogenes. Usually one mutation isn’t enough; most cells must undergo several mutations before they become cancerous. Sometimes the mutations must occur in sequence to create a cancer, sometimes random order will do. There are many causes of DNA damage, including radiation, free radicals, genetic defects, electrical fields, chemicals, drugs, viruses and metabolic stresses. Unquestionably, genetics plays a role; however, the genetic revolution continually provides insights into the role of diet in cancer prevention.

A number of studies have attempted to clarify the role of diet in the prevention of breast cancer. Results from the Women’s Intervention Nutrition Study (WINS), a large randomized clinical trial reported in 2005, suggested that a low-fat diet helped prevent breast cancer recurrence in postmenopausal women, especially those whose cancers didn’t respond to estrogen (ER-negative).¹ However, the researchers who conducted the 2006 Women’s Healthy Eating and Living (WHEL) study found only a slight, statistically insignificant reduction in breast cancer risk among women ages 50 to 79 who were able to lower their total fat intake.²

Soy and Breast Cancer

Among all the functional foods, soy products certainly capture consumers’ attention. Soy, and its specific plant chemicals called isoflavones, have displayed cancer-fighting activity in lab tests involving cancers of the prostate, breast and colon.

While some studies showed soy offers a protective effect against breast cancer, others showed the estrogen-like effects in isoflavones may be harmful for women with breast cancer. The College of Human Ecology in Seoul, Korea, carried out a case-control study examining the relationship between fruits, vegetables, soy foods and breast cancer risk in Korean women.³ Subjects were asked to indicate usual dietary habits, which were assessed using a semi-quantitative food frequency questionnaire. Results showed a high soybean intake had an inverse association of breast cancer in postmenopausal women, suggesting soybeans may be associated with a reduced breast cancer risk. However, a study in Japan offers contradicting evidence. Researchers in Nagoya, Japan, investigated whether soy foods really have protective effects against breast cancer by conducting a population-based prospective cohort study among Asian women.⁴ Over a two-year period, they analyzed data from 30,454 women, aged 40 to 79, regarding diet and other lifestyle features. During the mean follow-up of 7.6 years, 145 cases of breast cancer were documented. They found no significant association between the risk of breast cancer and the consumption of soyfoods; but they also found no protective effects against breast cancer either.

The American Institute for Cancer Research stresses data on soy and breast cancer is not conclusive, and more research is needed before any dietary recommendations can be made.

What is known at this point is the phytoestrogens in soy foods are “anti-estrogens”; they may block estrogen from reaching the body’s estrogen receptors, potentially protecting women from developing breast cancer. Pre-menopausal women may benefit from eating soy foods as their natural estrogen levels are high, but this may not be true to post-menopausal women as soy could become “pro-estrogenic” in women with low levels of natural estrogen. Concentrated soy supplements may add estrogen to the body and increase breast cancer risk in post-menopausal women.

Researchers at Brown University, Providence, R.I., noted interpretation of research regarding phytoestrogen intake and breast cancer risk is hampered by differences in dietary measurement, lack of standardization of supplemental sources, differences in metabolism among st individuals and the retrospective nature of much of the research in the area.⁵ They did suggest early exposure in childhood or early adolescence may be protective; however, the intervention studies conducted do not support a protective role.

A group of researchers from the Division of Preventive Oncology, Ontario, Canada, evaluated whether intake of phytoestrogens, specifically lignans and isoflavones, were associated with reduced breast cancer risk, using a novel phytoestrogen database.⁶ Randomly chosen breast cancer patients, aged 25 to 74 years, were identified using the Ontario Cancer Registry (n=3,063) and controls (n=3,430). An epidemiologic and food frequency questionnaire, which was expanded to include phytoestrogen-containing foods, was mailed to all subjects. Among all women, lignan intake was associated with a reduced breast cancer risk (Q5 vs. Q1 MVOR: 0.81, 95 percent CI: 0.65, 0.99); however, following stratification by body mass index (BMI), this reduction in risk was statistically significant only among overweight women (BMI > 25). Total phytoestrogen intake was also associated with a risk reduction among overweight women only. Among pre-menopausal women, total phytoestrogen intake was associated with a significant reduction in breast cancer risk among overweight women only (Q5 vs. Q1 MVOR: 0.51, 95 percent CI: 0.30, 0.87). Among postmenopausal women, no statistically significant association was observed between breast cancer risk and isoflavones or lignans. The researchers concluded lignan intake may be associated with reduced breast cancer risk among pre-menopausal women, with data suggesting BMI modifies the association.

Another study conducted in Bangkok, Thailand, investigated the pretreatment of the phytoestrogen-rich plant, Pueraria mirifica, and its effects on decreasing breast tumor incidence in rats.⁷ The rats were pretreated with P. mirifica tuberous powder at a dosage of 0, 10, 100 and 1,000 mg/kg BW/day for four consecutive weeks before induction of mammary tumors. Pretreatment of P. mirifica tuberous powder resulted in decreasing of the virulence of tumor development.

Collectively, lignans appear to offer a range of means that positively influence a favorable estrogen balance in the body. Canadian researchers studied the consumption of flaxseed (FS), and its effects in reducing the growth effect on established breast cancer.⁸ According to this study, FS, rich in lignans, which is metabolized to the mammalian lignans enterolactone (ENL) and enterodiol (END), consistently showed tumor inhibitory effects in a human clinical trial as well as rodent breast cancer models. Using the preclinical athymic mouse postmenopausal breast cancer model, combining FS with soy protein or GEN with END and ENL, was found to negate the tumor stimulatory effects of soy protein or GEN alone.

Antioxidant and anti-tumor effects of hydroxymatairesinol (as HMRlignan™, from Linnea), a lignan isolated from the knots of spruce, were studied in vitro in lipid peroxidation, superoxide and peroxyl radical scavenging, and LDL-oxidation models in comparison with the known synthetic antioxidants Trolox (a watersoluble vitamin E derivative), butylated hydroxyanisol (BHA) and butylated hydroxytoluene (BHT).⁹ The antitumor activity of HM-3000 was studied in induced rat mammary cancer, showing a positive result – a statistically significant inhibitory effect on tumor growth. In human studies, HM-3000 has been given in single doses, up to 1,350 mg, to healthy male volunteers devoid of treatment-related adverse events. Rapid absorption from the gastrointestinal tract and partial metabolism to enterolactone in humans was observed.

Complementary Therapies

Researchers at the University of Pennsylvania School of Medicine, Philadelphia, conducted a retrospective case-control study of the use of hormone-related supplements (HRS) and their association with breast cancer.¹⁰ Use of HRS varied significantly by race, with African American women being more likely than European American women to use any herbal preparation (19.2 percent vs. 14.7 percent, p=0.003) as well as specific preparations including black cohosh (5.4 percent vs. 2.0 percent, p=0.003), ginseng (12.5 percent vs. 7.9 percent, p<0.001) and red clover (4.7 percent vs. 0.6 percent, p<0.001). Use of black cohosh in this study appeared to have a significant breast cancer protective effect. This association was similar among women who reported use of either black cohosh or Remifemin (an herbal preparation derived from black cohosh).

Black cohosh extract (BCE) is commonly used to treat hot flashes and other symptoms associated with menopause. It is thought to have multiple mechanisms of action, including potential phytoestrogenic properties. However, researchers from the Department of Pharmaceutical Sciences, Toronto, Ontario, have questioned whether use of black cohosh (Cimicifuga racemosa [L.] Nutt.) by patients with hormone-sensitive cancer could be a concern.¹¹ Instead, they found black cohosh did not appear to exhibit phytoestrogenic activity and may inhibit tumor growth. Scientists at the University of Missouri-Columbia, Columbia, MO, concur black cohosh does not exert an estrogenic effect on the breast.¹² The study goals were to determine first the triterpene content of two commercially available BCE preparations, and second, the effect of BCE on circulating and breast-specific estrogenic markers. Two black cohosh preparations were analyzed for triterpene content. Postmenopausal women took BCE for 12 weeks followed by a 12-week washout. One BCE preparation contained trace amounts and another contained 2.5 percent triterpenes. Women taking BCE with 2.5 percent triterpenes experienced relief of menopausal symptoms, with reversion toward baseline after washout. BCE had no effect on estrogenic markers in serum. Triterpene content in commercially available black cohosh preparations varies. BCE standardized to 2.5 percent triterpenes relieved menopausal symptoms without systemic or breast-specific estrogenic effects.

Another botanical with a role to play in breast health is tea [Camellia sinensis (Theaceae)]. An inverse association between the intake of green tea polyphenols and the risk of breast cancer has been reported in Asian Americans. One epidemiological study has shown breast cancer progression is delayed in the Asian population that consumes green tea on regular basis.¹³ In this study, scientists report the effectiveness of green tea polyphenols (GTP) and its constituent epigallocatechin gallate (EGCG) in tumor regression using both in-vitro cell culture models and in vivo athymic nude mice models of breast cancer. Results suggest GTP and EGCG treatment inhibits proliferation and induce apoptosis of breast cancer cells in-vitro and in-vivo.

Because epidemiologic evidence that tea protects against breast cancer has been inconsistent, a case-control study in Southeast China investigated the prevention of breast cancer by use of green tea.¹⁴ The study participants included 1,009 women aged 20 to 87 years with histologically confirmed breast cancer, and 1,009 age-matched healthy controls. After adjusting established and potential confounders, green tea consumption was associated with a reduced risk of breast cancer. The odds ratios (OR’s) were 0.87 (0.73 -1.04) in women consuming between 1 and 249 g of dried green tea leaves per annum, 0.68 (0.54 - 0.86) for 250 to 499 g per annum, 0.59 (0.45 - 0.77) for 500 to 749 g per annum and 0.61 (0.48 - 0.78) for >or=750 g per annum, with a statistically significant test for trend (P < 0.001). Similar doseresponse relationships were observed for the duration of drinking green tea, number of cups consumed and new batches prepared per day. The result suggested regular consumption of green tea may protect against breast cancer; more research, however, to closely examine the relationship between tea consumption and breast cancer risk is warranted.

Essential fatty acids

have long been identified as possible oncogenic factors – omega-6 essential fatty acids (EFA) as prooncogenic and omega-3 EFA as anti-oncogenic factors.

Mary Enig, Ph.D., president of the Maryland Nutritionists Association, along with two colleagues, analyzed the claims made for cancer and fat intake: that the consumption of trans-fatty acids is strongly correlated with the incidence of breast cancer.¹⁵ Researchers at the Walter Reed Army Institute of Research, M.D., investigated the broad spectrum of biological functions.¹⁶ According to their research, omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) inhibit the growth of human breast cancer cells while the omega-6 fatty acids induce growth of these cells in animal models and cell lines.

The Epidemiology Research Unit in Montreal conducted a study with the objective to assess a possible association between specific and total carotenoids and breast cancer risk, and to evaluate the effects of diet-related fatty acids and lifestyle factors in the development of breast cancer.¹⁷ This population-based case-control study involved 414 cases and 429 controls. Dietary intake was estimated with the use of a validated food-frequency questionnaire in face-to-face interviews. The results suggest no significant association was apparent between any of the individual or total carotenoids and the risk of breast cancer after adjustment for major underlying determinants of breast cancer.

Another study, conducted in Montevideo, Uruguay, also investigated the relationship between the intake of different types of fat and breast cancer.¹⁸ The study comprised of 365 cases and 397 controls. It was determined a moderate and non-significant increase in breast cancer risk was associated with total fat intake. Saturated and monounsaturated fat intake were not associated to an increased risk of this malignancy, whereas polyunsaturated fat and linoleic acid were associated with a significantly reduced risk. On the contrary, both alpha-linolenic acid and cholesterol intakes were associated with an increased risk of breast cancer.

Building Long Term Health

Breast cancer treatment has vastly improved in recent years, and advances are continuously being made. This is great news for improving the health and survival odds for women with breast cancer, but it also means a confusing array of treatment options and often many months—even years—of treatment. Breast cancer is akin to other serious, chronic conditions, like heart disease and diabetes; it’s something a woman lives with and is vigilant about the rest of her life.

One of the big steps to take after completing treatment is to focus on what’s most important: good health. Awareness and knowledge – keys to natural breast health.

References

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2. http://www.breastcancer.org/tips/nutrition/new_research/20070717.jsp

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