Two new studies have examined the effects of certain dietary factors on recurrence of breast cancer in survivors. Soy had protective effects, and alcohol had detrimental effects. Read the full article on DrFuhrman.com.
Soy and breast cancer recurrence
Some individuals suspected and even promoted the idea that soy was potentially dangerous with regard to breast cancer risk, because of the phyto-estrogenic compounds it contains. However, in Asian countries where soy is a staple food, rates of breast cancer were much lower than those in the U.S. This paradox launched much debate and hundreds of studies on the relationship between soy and breast cancer.
A review of the most recent clinical studies on this subject supports a protective effect of soy:
- 2006: A meta-analysis in the Journal of the National Cancer Institute examining data from 18 studies on soy and breast cancer that were published between 1978 and 2004 concluded that soy overall has a protective effect.1
- 2008: A meta-analysis in the British Journal of Nutrition compiling data from 8 different studies (not included in the 2006 meta-analysis) also concluded that soy consumption decreases breast cancer risk. These effects were dose-dependent – a 16% reduced risk for each 10 mg of soy isoflavones consumed daily.2
In spite of these clear documented results, the myth that soy contributes to breast cancer has persisted. Plus, many scientists and physicians continue to doubt the safety of soy for current or previous breast cancer patients, because of soy’s phytoestrogen content.
A new study of breast cancer survivors has shown that these doubts are unwarranted too. Premenopausal breast cancer survivors who consumed more soy had a 23% reduced risk of recurrence.3
Which soy products are most beneficial?
Cruciferous vegetables are the most powerful anti-cancer foods. In addition, Dr. Fuhrman also recommends consuming a variety of beans, including soybeans, as components of an anti-cancer diet. Soybeans may be consumed as edamame (whole soybeans), or in minimally processed forms such as unsweetened soymilk, tofu, and tempeh. As little as 10 mg of soy isoflavones consumed per day has a protective effect with regard to breast cancer – this equates to approximately 1 ounce of one of these soy foods.
Alcohol and breast cancer recurrence
In contrast to the mainstream assumption that alcohol is heart healthy, even moderate amounts of alcohol are associated with increased risk for breast cancer.4
The current study of breast cancer survivors showed that women who consumed 3-4 alcoholic drinks per week were 34% more likely to experience a recurrence than the women who had less than 1 drink per week. This study was presented last week at the San Antonio Breast Cancer Symposium.5
Alcohol has no beneficial effect on the cardiovascular system, it only inhibits the blood’s clotting mechanisms. Since breast cancer is the second leading cause of death in women (second to cardiovascular disease), Dr. Fuhrman recommends minimizing alcohol consumption in order to reduce this risk.
Read the full article here.
Read “Dr. Fuhrman on Breast Cancer” to learn more diet and lifestyle strategies for breast cancer prevention.
References: 1. Trock BJ et al. Meta-analysis of soy intake and breast cancer risk. J Natl Cancer Inst. 2006 Apr 5;98(7):459-71. 2. Wu AH et al. Epidemiology of soy exposures and breast cancer risk. British Journal of Cancer (2008) 98, 9– 14 4. Lew JQ et al. Alcohol and risk of breast cancer by histologic type and hormone receptor status in postmenopausal women: the NIH-AARP Diet and Health Study. Am J Epidemiol. 2009 Aug 1;170(3):308-17. Epub 2009 Jun 18.
1. Trock BJ et al. Meta-analysis of soy intake and breast cancer risk. J Natl Cancer Inst. 2006 Apr 5;98(7):459-71.
2. Wu AH et al. Epidemiology of soy exposures and breast cancer risk. British Journal of Cancer (2008) 98, 9– 143. Guha N et al. Soy isoflavones and risk of cancer recurrence in a cohort of breast cancer survivors: the Life After Cancer Epidemiology study. Breast Cancer Res Treat. 2009 Nov;118(2):395-405. Epub 2009 Feb 17.
4. Lew JQ et al. Alcohol and risk of breast cancer by histologic type and hormone receptor status in postmenopausal women: the NIH-AARP Diet and Health Study. Am J Epidemiol. 2009 Aug 1;170(3):308-17. Epub 2009 Jun 18.