Red/processed meat consumption and noncancer-related outcomes in humans: Umbrella review


 The associations of red/processed meat consumption and cancer-related health outcomes have been well discussed. The umbrella review aimed to summarize the associations of red/processed meat consumption and various noncancer-related outcomes in humans. We systematically searched the systematic reviews and meta-analyses of associations between red/processed meat intake and health outcomes from PubMed, Embase, Web of Science and the Cochrane Library databases. The umbrella review has been registered in PROSPERO (CRD 42021218568). A total of 40 meta-analyses were included. High consumption of red meat, particularly processed meat, was associated with a higher risk of all-cause mortality, cardiovascular disease, and metabolic outcomes. Dose‒response analysis revealed that an additional 100 g/day red meat intake was positively associated with a 17% increased risk of type 2 diabetes mellitus (T2DM), 15% increased risk of coronary heart disease (CHD), 14% of hypertension, and 12% of stroke. The highest dose‒response per 50 g increase in processed meat consumption at 95% confident levels were 1.37 (1.22-1.55) for T2DM, 1.27 (1.09-1.49) for CHD, 1.17 (1.02-1.34) for stroke, 1.15 (1.11-1.19) for all-cause mortality, and 1.08 (1.02-1.14) for heart failure. In addition, red/processed meat intake was associated with several other health-related outcomes. Red and processed meat consumption seems to be more harmful than beneficial to human health in this umbrella review. It is necessary to take the impacts of red/processed meat consumption on noncancer-related outcomes into consideration when developing new dietary guidelines, which will be of great public health importance. However, more additional randomized controlled trials are warranted to clarify the causality.