Breast Cancer, Prostate Cancer, and Diet
Citations collected by George Eisman, R.D.
Men with a family history of breast cancer have an increased risk of
prostate cancer, and women with a family history of prostate cancer have an
increased risk of breast cancer. Epidemiology 9 (5) (1998) 525-529.
There is a link between animal protein and cancer, evident in both laboratory and human epidemiological studies. Journal of Surgical Research 59(2) (1995) 225-228.
A massive international study that contained data from 59 countries showed that men who ate the most meat, poultry and dairy products were the most likely to die from prostate cancer, while those who ate the most unrefined plant foods were the least likely to die from this disease. Journal of the National Cancer Institute 90 (21) (1998) 1637-1647.
As animal-derived food intake increases from once a week to four times a week, breast cancer rates increase by 70%. Japanese Journal of Cancer Research 85 (1994) 572-577.
A British study found low death rates for breast cancer where dairy product consumption was low, even when intake of other fats was high. British Journal of Cancer 24(1970), 633-43.
Studies that have failed to show a relationship between animal product consumption and breast cancer suffer from methodological problems. Journal of the National Cancer Institute 89 (1997) 766-775.
Among women younger than 50, having high IGF-1 (Insulin-like Growth Factor –1) levels raises breast cancer risk by seven times Lancet 351(1998), 1393-96.
In a study of 700 men, 233 of whom were vegan, serum IGF-1 was 9% lower in the vegans. British Journal of Cancer 83(1) (2000) 95-97.
In a study of men with prostate cancer, it was found that on average their serum IGF-1 was 8% higher than matched controls without active prostate cancer. Science 279 (1998), 563-6.
The 1,25 form of vitamin D in the body is lowered by diets rich in animal protein and/or too high in calcium. When blood levels of 1,25 vitamin D are depressed, IGF-1 becomes more active. Together these factors increase the birth of new cells while simultaneously inhibiting the removal of old cells, both favoring the development of cancer. This can result in 9.5 times increased risk of advanced stage prostate cancer. Journal of National Cancer Institute 94 (2002) 1099-1109.
And just in case you are worried that a dairy-free diet can lead to osteoporosis:
The Nurses’ Health Study (over 120,000 subjects) found that the consumption of milk does not protect against hip or forearm fractures. Those who drank 3 or more servings of milk a day actually had a slightly higher rate of fractures than women who drank little or no milk. American Journal of Public Health 87 (1997) 992-997