Breast cancer link to higher red meat consumption greeted with scepticism
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Version 0 of 1. Higher consumption of red meat in early adulthood could be associated with an increased risk of breast cancer and women might be able to lessen their chance of contracting the disease by consuming legumes, poultry, nuts and fish instead, a study has suggested. Analysing data from 88,803 premenopausal women aged 26 to 45 who, beginning in 1991, completed four-yearly questionnaires on diet, US researchers found that a higher intake of red meat was associated with a 22% increased risk of breast cancer overall, with each additional serving per day of red meat associated with a 13% increase in risk. Previous studies have suggested no significant association between red meat intake and the disease, and the study, published in the BMJ on Tuesdayyesterday, has been greeted with scepticism by experts who have said the results are not strong enough to overturn the consensus that there is no link. But the study authors, including Maryam Farvid from the department of nutrition at Harvard School of Public Health, say "most of the evidence has come from studies that evaluated diet during midlife and later". The study asked participants to identify categories of red meat intake from "never or less than once a month" to "six or more per day". The researchers also measured adolescent food intake for the study which adjusted for factors such as age, height, weight, race, family history of breast cancer, history of benign breast disease, and smoking. They identified 2,380 cases of breast cancer during 20 years of follow-up and used a statistical model to estimate breast cancer risks for women with different diets. The authors concluded: "Higher red meat intake in early adulthood may be a risk factor for breast cancer and replacing meat with a combination of legumes, poultry, nuts and fish, may reduce the risk of breast cancer." Substituting one serving of red meat each day for combined legumes, nuts, poultry, and fish was associated with a 14% lower risk of breast cancer, they said. Professor Valerie Beral, director of the cancer epidemiology unit at Oxford University, and leader of the Million Women's Study into the causes of the disease, said that there could be little confidence in such dietary-based studies. "Dozens and dozens of studies have looked at breast cancer risk associated with some aspect of diet," she said. "The totality of the available evidence indicates that red meat consumption has little or no effect on breast cancer risk, so results from a single study cannot be considered in isolation. "Diet is notoriously difficult to measure. The most reliable measure of meat consumption is whether or not people are vegetarian. Vegetarians do not have lower risks of breast cancer than non-vegetarians, further supporting other evidence that meat consumption is unlikely to play a major role in breast cancer." Professor Paul Pharoah, professor of cancer epidemiology at Cambridge University, said: "This is equivalent to an absolute increase of 4.2 cases per 1,000 women over 20 years for every additional portion of red meat eaten per day. This is a very small increase in risk." He added that "association does not necessarily imply causation". The researchers said further study of the relation between diet in early adulthood and risk of breast cancer was needed. |