There has been some suspicion that consumption of red meat may be a risk factor for breast cancer. A recent research study has indicated that premenopausal women who eat more than one and half servings of red meat
per day may double their risk of developing breast cancer compared with those who eat less than three serves of red meat per week.
Researchers from Harvard (1) studied the effects of red meat intake on the incidence of breast cancer among over 90000 premenopausal women by providing answers food questionnaires
in 1991, 1995 and 1999 with following up review until 2003. Every two years they reported whether or not they had developed breast cancer (only premenopausal women never diagnosed with cancer were
included in the reporting data).
At the end of the study, the women reporting the highest red meat intake were not at significantly greater risk for breast cancer overall but did show an increased risk of hormone receptor-positive cancer.
The risk
of hormone receptor-positive cancer was twice as high among women who ate more than 1.5 servings of red meat per day compared with those who ate red meat three or fewer times per week.
The researchers put forward a number of reasons why red meat may increase the risk of hormone receptor-positive cancer. These include:
Cooked red meats contain known cancer causing chemicals that increase mammary tumours in animals and may be linked to breast cancer in humans.
Growth hormones are used in cattle production and these could influence the risk of breast cancer.
The form of the iron in red meat may promote tumours.
They also suggested that it may be safer to stick to certified grass-fed beef rather than grain-fed beef as the fat profile of the grass-fed beef may contain fewer cancer-fueling omega-6 fats.
Modifying your diet by supplementing red meat with lean poultry, fish and plant-based proteins may be beneficial for your health on a number of levels. To understand more about your health and diet we suggest consulting a nutritionist or other suitably qualified health care professional.
(1) Cho E et al. "Red Meat Intake and Risk of Breat Cancer Among Premenopausal Women". Arch Intern Med 2006; 166;2253-2259