In the Pink Month or National Breast Cancer Awareness Month, the following is intended for breast cancer survivors.
A study published in Journal of American Medical Association suggests use of soy foods may help women diagnosed with breast cancer reduce risk of premature death and recurrence.
The study led by Shu X.O. and colleagues from Vanderbilt Epidemiology Center showed those who had highest intake of soy protein were 30 percent less likely to die or had recurrence of the disease during a 4-year follow-up.
Soy foods are high in isoflavones, phytoestrogens that have been associated with reduced risk of breast cancer in previous studies, according to the background information in the study report.
The study was meant to examine the effect of soy protein intake on the health in women who have already been diagnosed with breast cancer.
For the study, the researchers enlisted 5,042 female breast cancer survivors in China ages 20 to 75 years who participated in the Shanghai Breast Cancer Survival Study. The participants were diagnosed with the disease between March 2002 and April 2006 and followed up through June 2009.
During the 3.9-year follow-up, of 5,033 women who underwent surgery, 444 women died and 534 suffered recurrence or breast cancer related deaths.
The researchers found those who had highest intake of soy protein were 29 percent less likely to die and 32 percent less likely to have recurrence of breast cancer compared to those who had lowest intake.
The mortality rate among women having the highest intake of soy protein was 7.4 percent compared to 10.3 percent for those who had lowest intake.
The recurrence rate among those who ate highest amounts of soy foods was 8 percent compared to 11.2 percent among those who had the lowest intake.
The researchers concluded “Among women with breast cancer, soy food consumption was significantly associated with decreased risk of death and recurrence.”
More reports on diet and breast cancer will be released in the pink month.
New studies indicate that breast cancer survival rate may be increased with moderate soy consumption
Eating soy boosts breast cancer survival
Soy consumption for cancer patients has been the subject of some controversy. A new study has shown that breast cancer survivors who consume soy foods reap important health benefits and found that eating soy can increase the rate of survival for breast cancer patients.
According to a recent report published in the Journal of the American Medical Association (JAMA), women diagnosed with breast cancer and who consumed soy foods, such as tofu, soy milk, or edamame reduced their risk of recurrence by 32 percent. 1
Previous research refuted
Previous research had produced contradictory results with some studies suggesting that soy foods reduce the risk of breast cancer and others that compounds unique to soy may help breast cancer cells to grow. Now, previous theories been refuted with this new study demonstrating that soy does not increase the growth of breast cancer cells and has been proven to increase survival rates.
Higher soy intake – lower mortality
Researchers also found that breast cancer patients who consumed soy had a 29 percent decreased risk of death, compared to women who consumed little or no soy. Xiao Ou Shu, MD, PhD, lead researcher and professor of medicine at Vanderbilt University Medical Center in Nashville, TN, said, “Women who had a higher soy intake had a lower mortality and lower risk of relapse [than women with a low soy intake].”
Dr. Shu and her fellow researchers analyzed data from the Shanghai Breast Cancer Survival Study, the largest population-based study of breast cancer survival to date. The study included 5,042 women from 20 to 75 years of age and followed them for a period of four years.
Soy compounds reduce estrogen in the body
Soybeans are rich in phytoestrogens, also known as isoflavones. Although these substances are one thousand times less potent than human estrogen, there has been some concern that isoflavones may have an estrogen-like effect and may increase cancer risk.
However, many experts believe that because isoflavones fool the body into accepting the very weak compound, phytoestrogen actually competes with the human estrogen, thus reducing the overall level of estrogen in the body.
Soy is safe and potentially beneficial
An editorial accompanying this new study suggests some probable inconsistencies in prior research. The editorial attributed those inconsistencies to the fact that soy consumption in the U.S. is a good deal lower, which made the beneficial effects of consuming soy foods difficult to identify. In China, soy intake is higher and diets tend to include the intake of more traditional soy from food sources, rather than from soy supplements.
The researchers report, “The inverse association was evident among women with either estrogen receptor-positive or receptor-negative breast cancer and was present in both users and nonusers of tamoxifen.”
“In summary, in this population-based prospective study, we found that soy food intake is safe and was associated with lower mortality and recurrence among breast cancer patients.” These scientists concluded that, among women with breast cancer, soy food consumption was significantly associated with decreased risk of death and recurrence. Dr Shu and her colleagues stated, “This study suggests that moderate soy food intake is safe and potentially beneficial for women with breast cancer.”
1. Shu XO, Zheng Y, Cai H, et al. Soy food intake and breast cancer survival. JAMA. 2009;302:2437-2443. Ballard-Barbash R, Neuhouser ML. Challenges in design and interpretation of observational research on health behaviors and cancer survival. JAMA. 2009;302:2483-2484.
A new study finds that the isoflavone in soybeans can prevent a second stroke in individuals suffering from cerebrovascular events. According to the study published in The European Heart Journal, isoflavone reverses endothelial dysfunction in stroke sufferers.
Similar to cholesterol-lowering drugs, the chemical, also known as a phytoestrogen due to its estrogen-like effects, can improve the arterial blood flow in patients with a positive stroke history. Previous studies had reported that soy-rich diets can lower blood cholesterol levels and help prevent breast and prostate cancers. Isoflavones are also effective in lowering the risk of arteriosclerosis and other cardiovascular events.
University of Hong Kong scientists concluded that taking isoflavone dietary supplements can help reduce the risk of future strokes or cardiovascular events in stroke patients.
New research determines that dietary supplements rich in isoflavones may improve the function of arteries in stroke patients
A dietary supplement rich in isoflavones may improve the function of arteries in stroke patients, according to new research from Hong Kong.
The study is said to be the first randomized controlled trial investigating the effects of isoflavone supplements on improving the blood flow in the arm’s main artery in cardiovascular disease patients.
A daily 80 mg dose of isoflavones was associated with a one per cent increase in flow-mediated dilation (FMD), the measure of a blood vessel’s healthy ability to relax, according to findings published today in the European Heart Journal.
“Although the absolute increase in brachial diameter – one per cent – is small, the relative increase actually amounted to about 50 per cent because the mean average FMD in these stroke patients was about two per cent,” explained lead researcher Professor Hung-Fat Tse.
“These findings may have important implications for the use of isoflavone for secondary prevention in patients with cardiovascular disease, on top of conventional treatments,” wrote the authors in their EHJ paper.
Isoflavones from soy have been shown to provide a number of health benefits, including the promotion of heart health and the maintenance of bone health in post-menopausal women.
They have also been studied for their role in cancer prevention and slowing down the ageing process in peri-menopausal women, and isoflavone-rich supplements have proved to be a popular alternative to HRT for those wishing to control menopause symptoms without resorting to drugs.
Professor Tse and his co-workers from the University of Hong Kong recruited 102 stroke patients and randomly assigned 50 to receive daily isoflavone supplements (), and 52 to receive placebo, for 12 weeks.
“The specific dosage of 80 mg/day was chosen because previous studies have shown that isoflavone at this dosage was well tolerated by both men and women without significant side effects,” explained the researchers.
Ultrasound techniques were used to measure FMD at the start and end of the study. At the start, 80 per cent of the patients had an impaired FMD, defined as relaxation of less than 3.7 per cent. At the end of the 12 weeks, however, the patients receiving the isoflavone supplements experienced an improvement of one per cent, compared with the controls.
Moreover, the prevalence of impaired FMD after 12 weeks was only 58 per cent in the isoflavone group, compared to 79 per cent in the placebo group.
“The patients who had a lower initial FMD were found, in general, to respond with a larger absolute increase in FMD after receiving 12 weeks of isoflavone intervention, compared to patients who had a better baseline FMD in the first place,” said Prof Tse.
“These findings suggest that isoflavone reverses endothelial dysfunction in this group of patients with cardiovascular disease. This has important clinical implications, as the benefit of the [intervention] is conferred to the group of patients with the highest risks for cardiovascular events, and this effect persists, even at this rather late stage of the cardiovascular continuum.”
Supplementation with isoflavones was also associated with decreases in the levels of a protein called high-sensitivity C-reactive protein (CRP). This protein is a marker of inflammation and is reported to be an independent predictor of cardiovascular-related events.
“These findings suggested that isoflavone[s] alleviated vascular inflammatory stress and was an important component that mediated the reversal of endothelial dysfunction in this group of patients,” wrote the authors.
The mechanism by which the soy compounds is not totally understood, said Professor Tse. However, the anti-inflammatory effects may be related to the weak oestrogenic effect of the isoflavones. The female hormone oestrogen is known to protect against heart disease, said the researchers.
Despite the promising results of this clinical trial, the researchers stressed that it was too early to make any recommendations in this area.
“At this juncture, regular isoflavone supplement might not be advocated since the benefits and side effects of long-term supplementation are still unknown,” said Professor Tse.
“A balanced diet is still the top priority in promoting health. Diets with higher soy content might be beneficial due to the isoflavone contents. These food products also, in general, have higher contents of polyunsaturated fats, fibre, vitamins and less saturated fat.”
The FDA claims having 25 grams of soy protein a day, as part of a low-in-saturated-fat and cholesterol diet reduces heart disease risk.
Family: N.O. Fabaceae
Synonym: Coumestrol, daidzein, edamame, frijol de soya, genistein, greater bean, shoyu, soja, sojabohne, soybean
Habitat: The soybean is native to Southeastern Asia.
Soybean, classified as oilseeds, is an annual plant that does not grow more than five feet tall.
Part Used Medicinally:
Soybeans contain all the essential amino acids the body requires and is therefore a complete source of protein. Soybeans do not have any cholesterol, and are high in fiber. They have many vitamins, minerals, and phytochemical compounds (isoflavones). They are a rich source of calcium, iron, zinc, phosphorus, magnesium, B-vitamins, omega 3 fatty acids and fiber. Soybean oil is one of the few common vegetable oils that contain significant amount of aLNA and omega-6 fatty acids.
While the soybean’s high isoflavones, genistein and daidzein content prevents cancer, some consider it as the cause for thyroid and reproductive health problems. Isoflavones, with their estrogen-like properties, alleviate certain menopausal (hot flashes) and PMS symptoms. They also have favorable effects on cognitive function, particularly verbal memory and bone mineral density in postmenopausal women. Isoflavones are good for pre-menopausal women with cyclical breast pain and protect the body from hormone-related cancers. Soybean-rich diets can reduce testosterone levels in men. It is believed to be effective in preventing prostate cancer. Soy proteins provide antioxidants, reduce artery clogging plaques, improve blood pressure, boost the immune system, and lower the risk of atherosclerosis. Soy proteins lower LDL (bad cholesterol) and decrease blood clotting (thrombosis), which reduces the risk of heart attack and strokes. Their effect on HDL (good cholesterol) has not been proven. Soybeans are effective in treating gallbladder stones and Crohn’s disease. Their soluble fiber protects the body from cancers, such as colon and rectal malignancies. Soy proteins and soluble fibers help regulate glucose levels and kidney filtration especially in nephrotic syndrome. Soy is also effective in lowering blood pressure and sugar levels in individuals suffering from type 2 diabetes.
Natural soy milk contains about the same amount of protein as cow’s milk. Most commercially available soy milk is enriched with vitamins especially B12. Unlike cow’s milk it has little saturated fat and no cholesterol or casein, which many consider to be a benefit. It is also a rich source of lecithin and vitamin E.
Soy products contain sucrose as the basic disaccharide instead of galactose, it can safely replace breast milk in children with Galactosemia or in lactose-intolerant individuals. It is high in isoflavones, organic chemicals, polyunsaturated and monounsaturated fats which are good for the heart.
- Soy is traditionally considered to be safe during pregnancy and breastfeeding.
- Like milk, eggs, peanuts, fish, and wheat soy can also act as an allergen.
- While some studies claim soy protects against breast cancer, others show the estrogen-like effects of isoflavones may be harmful for women with breast cancer.
- Soy phytoestrogens disrupt endocrine function and have the potential to cause infertility, hypothyroidism and thyroid cancer.
- Soy formula has been linked to autoimmune thyroid disease in infants.
- Trypsin inhibitors in soy interfere with protein digestion and may cause pancreatic disorders.
- Soy-rich foods increase the body’s vitamin D requirement.