Greater red meat intake was strongly related to elevated risk of breast cancers that were estrogen and progesterone receptor positive.
Those that were estrogen and progesterone receptor negative have not been affected.
That means younger women consuming one-and-a-half portions of red meat a day nearly doubled their risk of hormone receptor-positive breast cancer compared to those who ate three or less servings per week, according to the study published in ARCHIVES OF INTERNAL MEDICINE.
The study was conducted throughout the 1990s in Boston, involving more than 90,000 pre-menstrual women. They reported back every two years about incidence of breast cancer, and also reported their consumption of 130 food products. Eventually, 1,021 women developed breast cancer, about half of them estrogen and progestrerone-positive cases.
The researchers said that the relation of breast cancer to red meat may be caused by cancer-causing chemicals created by cooking red meat, or perhaps there may be link to the growth hormones often fed to U.S. cattle. Additionally, red meat contains heme iron, found in other research to promote the growth of estrogen-related tumors.
Source: Archives of Medicine International