English beef and lamb levy body Eblex said the study by Harvard School of Public Health (HSPH) was only observational and conflicted with previous evidence found during controlled trials. “The conclusion that swapping a portion of red meat for poultry or fish each week may lower mortality risk was based only on a theoretical model. This conflicts with evidence from controlled trials, which have suggested that a simple switch from red meat to white meat or fish doesn’t provide the benefits anticipated by the theoretical model. Clearly other factors, such as body weight, fat intakes, physical activity and fruit/vegetable consumption, are also important,” said Eblex sector director Nick Allen.
Meat Advisory Panel Dr Carrie Ruxton referred to other recent studies to contradict the findings of the report. “In a recent intervention study, which compared a healthy, low meat diet (28g/day) with a healthy, high meat diet (156g/day), both groups experienced improvements in heart health indicators such as LDL blood cholesterol levels. In two other studies, meat diets were switched for fish diets and markers of colorectal cancer risk, (for example, apoptosis in colon cells, toxicity of faecal water) were studied. Neither study showed a significant reduction in risk, even after six months. This suggests that a simple switch from red meat to white meat or fish doesn’t provide the benefits anticipated by the theoretical model,” she said.
Asked about the other factors contributing to mortality rates, An Pan, HSPH researcher and one of the study’s authors, told GlobalMeatNews: “We have carefully controlled (taken into consideration) all these lifestyle factors in our statistical models, so the associations we reported in the paper were independent of body mass index, smoking, alcohol and physical activity. But certainly, as in any observational studies, residual confounding is possible. But given the comprehensive information and high-quality data we have, the residual confounding by these lifestyle factors would be small.”
Study deemed "unreliable"
The study, published in the Archives of Internal Medicine, associated red meat intake with increased risk of premature death, especially from cardiovascular diseases and cancer. It said one daily intake of unprocessed red meat increased that risk by 13%, and the percentage reached 20% for processed meat.
The American industry rejected the findings as “unreliable”. Shalene McNeill, executive director of human nutrition research at the National Cattlemen’s Beef Association, said: “The scientific evidence to support the role of lean beef in a healthy, balanced diet is strong and there is nothing in this study that changes that fact. Research clearly shows that choosing lean beef as part of a healthful diet is associated with improved overall nutrient intake, overall diet quality and positive health outcomes. Overall, lifestyle patterns including a healthy diet and physical activity, not consumption of any individual food, have been shown to affect mortality.”
At the National Pork Board, registered dietician Adria Sheil-Brown added: “Both coronary heart disease and cancer have many risk factors and simply cutting out or limiting the intake of one particular type of food will not prevent these diseases. The total body of research continues to show that excess weight, lack of activity and smoking are the greatest risk factors for cancer. There is no health-based rationale for substituting one lean protein for another.”
Eblex also deplored the widespread media coverage the study received. Allen said: “What is more concerning than the study itself is the continued willingness of the media to publish over-simplistic, misleading stories without any real understanding of the statistics involved, and with a sensational headline not borne out by the content of the story. (...) The continual drip-drip effect of stories risk turning consumers off to the benefits of eating home-produced red meat.”