The incidence of breast cancer in the United States began
climbing steadily in the early 1970s, and is now the highest ever seen in human
history. Nearly 50,000 American women die of the disease every year. In the
face of this tragedy, a great deal of attention has been given to genetics, but
the presence of the breast cancer susceptibility gene, called BRCA-1, only
accounts for at most 5 percent of breast cancers.
Exercise is very important to breast cancer risk. In fact,
women who exercise (walk) for four
hours per week lower their risk by 33 percent. And women who exercise more than that lower their risk even further. [29]
But diet, it turns
out, is even more important. . .
What We Know
Death rate from
breast cancer in the United States: 22.4 (per 100,000)
Death rate from
breast cancer in Japan: 6.3 (per 100,000)
Death rate from
breast cancer in China: 4.6 (per 100,000)
Primary reasons for
difference: People in China and Japan eat more fruits and vegetables and less
animal products, weigh less, drink less alcohol, and get more exercise than
people in the United States.
Breast cancer rate for women in Italy who eat a lot of animal products compared to women in Italy who don't: 3 times greater [30]
Breast cancer rate
for women in Uruguay who eat meat often compared to women in Uruguay who rarely
or never eat meat: 4.2 times greater [31]
Breast cancer rate
for affluent Japanese women who eat meat daily compared to poorer Japanese
women who rarely or never eat meat: 8.5 times greater [32]
Impact on breast
cancer risk for adult women who are 45 pounds overweight: Double [33]
American women who
are aware that there are any dietary steps they can take to lower their chances
of developing breast cancer: 23 percent [34]
American women with
less than high school educations who are aware that there are any dietary steps
they can take to lower their risk of developing breast cancer: 3 percent [35]
American women who
believe that mammograms prevent breast cancer: 37 percent [36]
References
[29] Thune, I., et al., "Physical Activity and the
Risk of Breast Cancer," New England Journal of Medicine 336 (1997): 1269-75.
[30] Decarli, A, et al., "Macronutrients, Energy Intake
and Breast Cancer Risk. . . ," Epidemiology
8 (1997):425-28; see also Wynder, E., et al., "Breast Cancer: Weighing the Evidence for a
Promoting Role of Dietary Fat," Journal of the National Cancer Institute 89 (1997):766-75; Nicholson, A, "Diet
and the Prevention and
Treatment of Breast Cancer," Alternative Therapies 2 (1996):32-8; and Outwater, J., et
al., "Dairy Products and Breast Cancer. . . ," Medical Hypotheses 48 (1997):453-61.
[31] Ronco, E., et al., "Meat, Fat, and Risk of Breast Cancer:
A Case Control Study from Uruguay," International Journal of Cancer 65
(1996):328-31.
[32] Hirayama, T., "Epidemiology of Breast Cancer with
Special Reference to the Role of Diet," Preventive Medicine 7 (1978):173-95.
[33] Huang, Z., et al., Journal of the American Medical
Association (1997), cited in 'Weight Gain Increases Risk of Breast
Cancer," Associated Press, November 4, 1997.
[34] Bamard, N. D., et al., "Beliefs about Dietary
Factors in Breast Cancer among American Women, 1991-1995," Preventive
Medicine 26 (1997): 109-13.
[35] Ibid.
[36] Ibid.
[37] Hirayama, T., "Diet and Cancer," Nutrition
and Cancer 1 (1979a):67-81. See also Colditz, G. A., et al., "Diet and
Lung Cancer: A Review of the Epidemino-logic Evidence in Humans,” Archives of
Internal Medicine 147 (1987): 157-60; and International Journal of Cancer 78
(1998): 430-6, cited in “fruits, Carrots May Reduce Lung Cancer Risk,” Reuters,
November 25, 1999.
(‘The Food
Revolution: how your diet can help save your life and our world’, by John
Robbins)