http://archinte.jamanetwork.com/ en-us Mon, 17 Jun 2013 00:00:00 GMT Mon, 17 Jun 2013 16:45:00 GMT Silverchair editor@archinte.jamanetwork.com webmaster@archinte.jamanetwork.com http://archinte.jamanetwork.com/article.aspx?articleID=1697785 Mon, 17 Jun 2013 00:00:00 GMT Pan A, Sun Q, Bernstein AM, et al. <span class="paragraphSection"><div class="boxTitle">Importance</div>Red meat consumption has been consistently associated with an increased risk of type 2 diabetes mellitus (T2DM). However, whether changes in red meat intake are related to subsequent T2DM risk remains unknown.<div class="boxTitle">Objective</div>To evaluate the association between changes in red meat consumption during a 4-year period and subsequent 4-year risk of T2DM in US adults.<div class="boxTitle">Design and Setting</div>Three prospective cohort studies in US men and women.<div class="boxTitle">Participants</div>We followed up 26 357 men in the Health Professionals Follow-up Study (1986-2006), 48 709 women in the Nurses' Health Study (1986-2006), and 74 077 women in the Nurses' Health Study II (1991-2007). Diet was assessed by validated food frequency questionnaires and updated every 4 years. Time-dependent Cox proportional hazards regression models were used to calculate hazard ratios with adjustment for age, family history, race, marital status, initial red meat consumption, smoking status, and initial and changes in other lifestyle factors (physical activity, alcohol intake, total energy intake, and diet quality). Results across cohorts were pooled by an inverse variance–weighted, fixed-effect meta-analysis.<div class="boxTitle">Main Outcomes and Measures</div>Incident T2DM cases validated by supplementary questionnaires.<div class="boxTitle">Results</div>During 1 965 824 person-years of follow-up, we documented 7540 incident T2DM cases. In the multivariate-adjusted models, increasing red meat intake during a 4-year interval was associated with an elevated risk of T2DM during the subsequent 4 years in each cohort (all P < .001 for trend). Compared with the reference group of no change in red meat intake, increasing red meat intake of more than 0.50 servings per day was associated with a 48% (pooled hazard ratio, 1.48; 95% CI, 1.37-1.59) elevated risk in the subsequent 4-year period, and the association was modestly attenuated after further adjustment for initial body mass index and concurrent weight gain (1.30; 95% CI, 1.21-1.41). Reducing red meat consumption by more than 0.50 servings per day from baseline to the first 4 years of follow-up was associated with a 14% (pooled hazard ratio, 0.86; 95% CI, 0.80-0.93) lower risk during the subsequent entire follow-up through 2006 or 2007.<div class="boxTitle">Conclusions and Relevance</div>Increasing red meat consumption over time is associated with an elevated subsequent risk of T2DM, and the association is partly mediated by body weight. Our results add further evidence that limiting red meat consumption over time confers benefits for T2DM prevention.</span> 1 8 10.1001/jamainternmed.2013.6633 http://archinte.jamanetwork.com/article.aspx?articleID=1697785 http://archinte.jamanetwork.com/article.aspx?articleID=1697792 Mon, 17 Jun 2013 00:00:00 GMT Evans WJ. <span class="paragraphSection">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 (T2DM). While previous studies have been cross-sectional in nature, the present study demonstrated that a relatively short-term (4-year) increase in red meat consumption is associated with subsequent risk, even in individuals who initially consumed low amounts of red meat. The authors demonstrated that consuming more red meat is also associated with weight gain, and a statistical adjustment for change in body weight attenuates but does not eliminate the risk, indicating that increased weight is not the only cause of a greater risk of T2DM associated with red meat consumption. The data in this article are valuable for those considering strategies to decrease the risk of developing T2DM.</span> 1 2 10.1001/jamainternmed.2013.7399 http://archinte.jamanetwork.com/article.aspx?articleID=1697792