Greenhouse gas implications of introducing cultured meat into German and Italian diets: A comparison of substitution and optimized dietary scenarios

Reducing the environmental footprint of food consumption is essential for achieving climate targets, and there is growing interest in understanding whether novel foods such as cultured meat (CM) can meaningfully contribute to lowering diet-related greenhouse gas (GHG) emissions in different national contexts. This study assesses the GHG implications of introducing CM into current German and Italian diets and in nutritionally optimized dietary patterns. Food intake data from the EFSA Comprehensive Database were used to construct country-specific baseline diets, from which six substitution scenarios were created by progressively replacing bovine, pork, poultry, sausages, processed meat, or a weighted average meat portion with CM on a protein-equivalent basis. A Monte Carlo approach (±20% variation in intake and emission factors) was used to account for realistic dietary variability. Linear programming was subsequently used to derive nutritionally optimized diets that were constrained to be within ±20% of current food-group consumption to ensure cultural acceptability. Meat was the most significant contributor to dietary GHG emissions (28% in Germany; 48% in Italy). CM reduced emissions only when substituting bovine meat, whereas replacing other meats consistently increased emissions. Optimized diets lowered emissions by 23% (Germany) and 19% (Italy) but introducing CM in these optimized diets provided no additional mitigation. Energy demand analyses show that large-scale CM production would require renewable energy expansion far beyond current national capacities. Overall, currently, CM shows limited short-term potential to reduce diet-related emissions unless used explicitly as a bovine meat replacement and supported by substantial improvements in production efficiency and the availability of clean energy. • Cultured meat reduces GHG emissions when replacing bovine meat in German and Italian diets. • Substituting meats different from the bovine with cultured meat increases GHG emissions. • Diet optimization under realistic ±20% acceptability constraints lowers emissions by 19–23%. • Adding cultured meat to optimized diets provides no additional environmental benefit. • Meeting current demand with cultured meat requires an expansion of renewable energy capacity.