Environmental impact of diet from the INRAN-SCAI Survey: role of food groups and health determinants

Abstract Background The environmental impacts of food consumption, specifically carbon footprint (CF) and water footprint (WF), are gaining increasing importance in the context of global sustainability and public health. This study evaluates the contribution of different food groups to environmental footprints and examines how health determinants such as gender, age, BMI, geographic location, and adherence to the Mediterranean diet (MD) influence these impacts. The goal is to better understand how dietary habits affect environmental sustainability and to provide data-driven recommendations for policy development. Methods This cross-sectional study utilised data from 2,831 participants in the third INRAN-SCAI Survey, conducted across various regions of Italy in 2005. CF and WF were calculated by multiplying the daily consumption of each food product by their respective environmental coefficients. We performed regression analyses to assess the association between health determinants and adherence to the MD to environmental footprints. Results The average CF was 3.53 kg CO2 eq/day, and the average WF was 3,330.96 L/day. Red meats (1.08 kg CO2 eq; 657.24 L) and dairy products (0.28 kg CO2 eq; 708.62 L), were the largest contributors to CF and WF. Males had higher environmental impacts (3.92 kg CO2eq; 3,691 L) than females (3.21 kg CO2 eq; 3,037 L) (p < 0.001), as well as younger individuals (3.76 kg CO2 eq; 3,491 L) versus older adults (3.12 kg CO2 eq; 2,948 L) (p < 0.001). Greater adherence to the MD was associated with reduced environmental impact (p < 0.001), with lower CF (β = -0.226) and WF (β = -189.966). Conclusions Animal-based foods are the primary drivers of the environmental impact of diets in Italy. Significant variations in CF and WF were observed by gender, age, and MD adherence. These findings highlight the need for public health strategies aimed at promoting dietary shifts to address the broader challenges of climate change and water scarcity. Key messages • Animal-based foods, gender, and age significantly influence the carbon and water footprints of individual diets. • Adherence to MD is associated with lower environmental impacts.