Red meat and processed meat intake has been linked to increased risk of type 2 diabetes; however, evidence from Asia is limited and inconsistent. We prospectively examined the association of intake of total meat and its subtype with type 2 diabetes in a Japanese working population. Participants were 2709 workers aged 18–78 years who reported no history of diabetes when they responded to a health survey for the first time between 2012 and 2019. Dietary intake was assessed using a validated self-administered diet history questionnaire. The incidence of type 2 diabetes was assessed via annual health checkups from baseline through March 2023. Type 2 diabetes was defined as fasting blood glucose ≥ 126 mg/dl, casual blood glucose ≥ 200 mg/dl, HbA1c ≥ 6·5 %, self-report of diabetes or current use of anti-diabetic drugs. Hazard ratios according to tertile of meat intake were estimated using Cox proportional hazards regression. During 16 119 person-years of follow-up, 135 (5·0 %) workers developed type 2 diabetes. Intakes of total meat, red meat, processed meat and poultry were not associated with risk of type 2 diabetes. After adjustment for covariates, hazard ratios for the highest v. lowest tertile of meat intake were 1·01 (95 % CI 0·63, 1·62) for total meat, 1·02 (95 % CI 0·66, 1·58) for red meat, 0·99 (95 % CI 0·65, 1·49) for processed meat and 1·13 (95 % CI 0·71, 1·80) for poultry. Our findings suggest that meat intake is not associated with the risk of type 2 diabetes among Japanese workers.

We explored the role of lipid accumulation products and visceral adiposity on the association between red meat consumption (RMC) and markers of insulin resistance (IR) and inflammation in USA adults. Data on RMC and health outcome measurements were extracted from the 2005–2010 US National Health and Nutrition Examination Surveys. Overall 16 621 participants were included in the analysis (mean age = 47·1 years, 48·3 % men). ANCOVA and ‘conceptus causal mediation’ models were applied while accounting for survey design. In adjusted models, a lower RMC was significantly associated with a cardio-protective profile of IR and inflammation. BMI had significant mediation effects on the association between RMC and C-reactive protein (CRP), apo B, fasting blood glucose (FBG), insulin, homoeostatic model assessment of IR and β-cell function, glycated Hb (HbA1c), TAG:HDL ratio and TAG glucose (TyG) index (all Ps < 0·05). Both waist circumference and anthropometrically predicted visceral adipose tissue mediated the association between RMC and CRP, FBG, HbA1c, TAG:HDL ratio and TyG index (all Ps < 0·05). Our findings suggest that adiposity, particularly the accumulation of abdominal fat, accounts for a significant proportion of the associations between red meat consumption, IR and inflammation.

Knowledge regarding association of dietary branched-chain amino acid (BCAA) and type 2 diabetes (T2D), and the contribution of BCAA from meat to the risk of T2D are scarce. We evaluated associations between dietary BCAA intake, meat intake, interaction between BCAA and meat intake and risk of T2D. Data analyses were performed for 74 155 participants aged 50−79 years at baseline from the Women’s Health Initiative for up to 15 years of follow-up. We excluded from analysis participants with treated T2D, and factors potentially associated with T2D or missing covariate data. The BCAA and total meat intake was estimated from FFQ. Using Cox proportional hazards models, we assessed the relationship between BCAA intake, meat intake, and T2D, adjusting for confounders. A 20 % increment in total BCAA intake (g/d and %energy) was associated with a 7 % higher risk for T2D (hazard ratio (HR) 1·07; 95 % CI 1·05, 1·09). For total meat intake, a 20 % increment was associated with a 4 % higher risk of T2D (HR 1·04; 95 % CI 1·03, 1·05). The associations between BCAA intake and T2D were attenuated but remained significant after adjustment for total meat intake. These relations did not materially differ with or without adjustment for BMI. Our results suggest that dietary BCAA and meat intake are positively associated with T2D among postmenopausal women. The association of BCAA and diabetes risk was attenuated but remained positive after adjustment for meat intake suggesting that BCAA intake in part but not in full is contributing to the association of meat with T2D risk.

The aims of the present study were to verify the proportion of population that consumed more red and processed meat than the World Cancer Research Fund (WCRF) dietary recommendation, to estimate the environmental impact of beef intake and the possible reduction of greenhouse gas emissions if the dietary recommendation was followed. We used the largest, cross-sectional, population-based survey entitled the National Dietary Survey (34 003 participants aged 10–104 years). The usual meat intake was obtained by two food records completed on 2 non-consecutive days. The usual intake was estimated by the multiple source method. The environmental impact was analysed according to estimates of CO2 equivalent emissions from beef intake as a proxy for beef production in Brazil. The red and processed meat intake mean was 88 g/d. More than 80 % of the population consumed more red and processed meat than the WCRF recommendation. Beef was the type of meat most consumed, accounting to almost 50 %. Each person contributed 1005 kg of CO2 equivalents from beef intake in 2008, the same quantity of CO2 produced if a car travelled a distance between the extreme north and south of Brazil (5370 km). The entire Brazilian population contributed more than 191 million tons of CO2 equivalents, which could have been reduced to more than 131 million tons if the dietary recommendation was followed. The present study shows that the magnitude of the excessive red and processed meat intake in Brazil can impact on health and the environment, pointing to the urgency of promoting a sustainable diet.

In early epidemiological studies of diet and cancer the stress was on the search for causal factors. Population (ecological) studies tended to show a strong correlation between meat intake, particularly red meat, and the risk of colo-rectal cancer. They also tended to show meat to be strongly inversely correlated with cancers of the stomach and oesophagus and liver. Early case- control studies tended to support the postulated role for red meat in colo-rectal carcinogenesis, although more recent case-control studies, particularly those from Europe, have tended to show no relationship. The cohort studies in general failed to detect any relationship between meat intake and colo-rectal cancer risk. The available evidence points to the intake of protective factors such as vegetables and whole-grain cereals being the main determinants of colo-rectal cancer risk, with meat intake only coincidentally related.