Study links red meat consumption to heightened diabetes risk

The research, a follow-up of three studies covering around 149,000 men and women in the United States, was published by JAMA Internal Medicine.

While red meat has been consistently associated with an increased risk of T2DM, previous studies only measured consumption at a baseline with limited follow-up information.

However, a person's eating behaviour is likely to change over years and measuring consumption at a single point in time does not capture the variability of intake during follow-up, the authors noted.

In-depth follow-up​

An Pan, of the National University of Singapore, and colleagues analysed data from three Harvard group studies and then invited them to answer a questionnaire to assess their diets.

The follow-up took more 1.9m people-years as researchers documented 7,540 incident cases of T2DM.

"Increasing red meat intake during a four-year interval was associated with an elevated risk of T2DM during the subsequent four years in each cohort​," according to the study.

The results indicate that compared to a group with no change in red meat intake, those who increased their red meat intake of more than 0.50 servings per day saw a 48% higher risk over the subsequent four-year period.

Moreover, reducing red meat consumption by more than 0.50 servings per day from the baseline over the same time period resulted in a 14% lower risk.

"Our results confirm the robustness of the association between red meat and T2DM and add further evidence that limiting red meat consumption over time confers benefits for T2DM prevention​," the authors concluded, noting the study was observational so causality cannot be inferred.

However, Pan later speculated to Bloomberg that high amounts of iron in the meat might cause insulin resistance, which had the potential to raise the risk of diabetes. The food is also high in saturated fat and cholesterol and processed forms have nitrates and high levels of sodium that may also increase the danger of developing the disease.

Quality of meat​

However, in an accompanying editorial, head of the Muscle Metabolism Discovery Performance Unit at GlaxoSmithKline in London and an adjunct professor at Duke University Medical Centre, wrote that it may be the fat in the meat that raised the risk of diabetes, not the type of meat.

"The article by Pan et al confirms previous observations that the consumption of so-called red meat is associated with an increased risk of type 2 diabetes mellitus​.

"Perhaps a better description of the characteristics of the meat consumed with the greatest effect on risk is the saturated fatty acid content, rather than the amount of oxygen-carrying proteins​.

"A recommendation to consume less red meat may help to reduce the epidemic of T2DM. However, the overwhelming preponderance of molecular, cellular, clinical and epidemiological evidence suggests that public health messages should be directed toward the consumption of high-quality protein that is low in total and saturated fat​,” Evans concluded.

Source: JAMA Intern Med. Published online June 17, 2013. doi:10.1001/jamainternmed.2013.6633.