However, according to data from 319,826 women, high intakes of processed meat were linked to a slight increase in the risk of breast cancer in post-menopausal women, and high butter intakes were linked to a slight increase in the risk of breast cancer in pre-menopausal women.
But overall a null results was observed, state the EPIC researchers in the American Journal of Clinical Nutrition.
In an accompanying editorial, Eleni Linos from Stanford University Medical Center and Walter Willett from Harvard School of Public Health stated: “We are now fortunate to have reports from many large cohort studies conducted worldwide, which include well over one million women and many thousands of cases of breast cancer, that are quite consistent in showing no overall relation of meat or dairy products consumed in midlife or later to breast cancer risk.
“Although more data on diet in childhood and early adult life are needed, and on the effects of high temperature cooking, these data are sufficient to exclude any major effect of consuming these foods during midlife or later on risk of breast cancer.”
While the results of the study do appear to allay fears of animal fat intakes and breast cancer, concerns still abound in relation to other forms of cancer, most notably lung, pancreatic and colorectal cancer.
Indeed, a body of research blames excessive red meat consumption for a number of health problems, including higher rates of heart disease, macular degeneration, various cancers and premature death.
Study details
During the course of almost nine years of study, the EPIC researchers, led by Valeria Pala from the IRCCS National Cancer Institute in Milan, documented 7,119 cases of breast cancer.
Overall, they found not “consistent association […] between breast cancer risk and the consumption of any of the food groups under study”, wrote Pala and her co-workers.
High intakes of processed meats were associated with a “modest” 10 per cent increase in breast cancer risk for post-menopausal women, while increased butter intakes amongst pre-menopausal women were associated with a 28 per cent increase in the risk of breast cancer.
“Future studies should investigate the possible role of high-temperature cooking in the relation of red meat intake with breast cancer risk,” they concluded.
Important results
Commenting on the study, Shelley McGuire, PhD, spokesperson for the American Society for Nutrition said it pointed toward two very important points. "First we all need to remember that there are really no such things as 'bad' foods.
“Second, observational studies that show associations between diet and health need to be considered with a proverbial grain of salt. These studies clearly provide additional and strong evidence that consumption of meat and dairy products by women does not, by itself, increase breast cancer risk.”
Linos and Willet added that “nevertheless, good reasons still exist for keeping consumption of red meat low, because this will likely help reduce risks of coronary heart disease and type-2 diabetes.
“Also, for women looking to reduce their risk of breast cancer by nutritional means, solid evidence documents that avoidance of weight gain during adult life and low alcohol consumption will be effective.”
Source: American Journal of Clinical Nutrition
September 2009, Volume 90, Pages 602-612
“Meat, eggs, dairy products, and risk of breast cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort”
Authors: V. Pala, V. Krogh, F. Berrin, et al.
Pages 455-456
“Meat, dairy, and breast cancer: do we have an answer?”
Authors: E. Linos, W. Willett