Systematic review of reducing population meat consumption to reduce greenhouse gas emissions and obtain health benefits: effectiveness and models assessments.

OBJECTIVES: This review evaluates existing co-benefit models for emission and health outcomes of counterfactual scenarios of reduced meat consumption at a population level.
METHODS: A novel assessment process was developed, combining selected measures from the Cochrane Review quality assessment tools, from the PRISMA checklist, and model quality measures identified by the authors during the preliminary phases of the review process.
RESULTS: Four emission models and three health outcome models have been identified which show great variation in model characteristics and qualities. The estimated counterfactual scenario emission effects presented in the included studies ranged from a reduction of <3-30 % and reduction in the burden of disease ranged from 1 to 16 %. Meta-analysis could not be conducted due to high heterogeneity of model characteristics.
CONCLUSIONS: All co-benefit studies estimated that reducing population meat consumption could reduce greenhouse gas emissions and the burden of disease. However, important attention must be paid to nutrition balance and a systematic approach in input and output attribute parameters is recommended for better model quality.