How much does overnutrition weigh? The environmental and social impacts of Metabolic Food Waste in Italy

Excess Food Energy Intake (EFEI), namely Metabolic Food Waste (MFW) corresponds to excess calorie intake related to overconsumption of food and is responsible for overweight (OW) and obesity (OB) conditions. Identifying its causes and impacts could be important, so that it can be prevented and reduced, generating health, environmental and societal benefits. Therefore, this research quantifies MFW among OW and OB adult populations (18–75 years) in Italy and its environmental and social implications. Life cycle assessment (LCA) through the Simapro 9.5 software was used and then, the results were monetized according to the Environmental Price Handbook to understand the real environmental cost. Finally, Social LCA (S-LCA) was considered following the Product Social Impact Assessment (PSILCA) guidelines to understand the potential social risks behind the food that ends up on our plates. The results highlight the amount of MFW in Italy is 2696 billion kcal/year corresponding to 1.59 Mtons over-consumed food/year, while the impacts are mainly related to global warming (8.78 Mtons CO2 eq/year, or 2.29 % of the total Italian CO2 emissions), terrestrial ecotoxicity (843,451 tons 1.4-DCB/year), freshwater ecotoxicity (222,483 tons 1.4 DCB eq/year), and land consumption (8 million m2a eq/year), mostly due to the meat, fats and oils and sweets overconsumption. Impacts monetization also shows that MFW could induce an environmental price of € 1340/per capita/year, and finally, the S-LCA reveals how overconsumption of food has the potential to affect gender discrimination, water depletion, trade union, and social discrimination due to the high proportion of labor migrants in the agricultural sector.