12 January - 20 June 2016

Disagreement over breast cancer risk from red meat

18 June 14

A recent paper published in the British Medical Journal has claimed that women who consume a greater amount of red meat in early adulthood have up to a 22% higher relative risk of developing breast cancer in later life. The paper has sparked a debate between experts in the area; previous work has shown no clear link between red meat and breast cancer, and some scientists have raised concerns or expressed doubt about the Harvard study's conclusions.

Unlike previous research, which had for the most part involved older subjects, premenopausal women aged 26-45 from the US Nurses' Health Study II were selected for this study. This enabled the authors to look at the link between the 88,803 women's early adulthood diets and their risk of developing breast cancer over a 20-year period. The participants were asked to complete semi-quantitative questionnaires in 1991, rating their frequency of consumption of various foods on a nine-point scale ranging from 'never or less than once per month' to 'six or more per day'. The researchers also looked at the subjects' adolescent food consumption, and adjusted for variables including, but not limited to: age, height, weight, family history of breast cancer, history of benign breast cancer, smoking, race, age at first birth, age at menopause and postmenopausal hormone use. Analysis of this data showed a relative risk increase of developing breast cancer of 22% when comparing the group in the lowest fifth of total red meat intake (median 0.14 servings/day) with the highest fifth (median 1.50 servings/day).

These conclusions have been met with some scepticism, partly due to conflict with previous research findings, and partly to perceived weaknesses in the methodology. One criticism, for example, was that the study relied heavily on the women's recollection of their diet. Professor Valerie Beral, director of the cancer epidemiology unit at Oxford University, was quoted in the Guardian noting that "vegetarians do not have lower risks of breast cancer than non-vegetarians...[which supports] other evidence that meat consumption is unlikely to play a major role in breast cancer." Another sceptical voice came from Professor Tim Key, an epidemiologist at Oxford University, whom the BBC reported as saying the study found "only a weak link" and was "not strong enough to change the existing evidence that has found no definite link between the two."

Whilst there is evidence that consuming red meat is linked to bowel cancer, there is certainly no consensus as yet regarding its effect on breast cancer risk, and so further research is required before drawing firm conclusions or making new dietary recommendations.

share this article
RSSL endeavours to check the veracity of news stories cited in this free e-mail bulletin by referring to the primary source, but cannot be held responsible for inaccuracies in the articles so published. RSSL provides links to other World Wide Web sites as a convenience to users, but cannot be held responsible for the content or availability of these sites. This document may be copied and distributed provided the source is cited as RSSL's Food e-News and the information so distributed is not used for profit.

Previous editions

Load more editions

Make an Enquiry