Background Suboptimal diets are a major contributor to cardiometabolic disease (CMD) mortality, and substantial disparities exist for both dietary quality and mortality risk across income groups in the USA. Research is needed to quantify how food pricing policies to subsidise healthy foods and tax unhealthy foods could affect the US CMD mortality, overall and by Supplemental Nutrition Assistance Program (SNAP) eligibility and participation.

Methods Comparative risk analysis based on national data on diet (National Health and Nutrition Examination Survey, 2003–2012) and mortality (mortality-linked National Health Interview Survey) and meta-analyses of policy-diet and diet-disease relationships.

Results A national 10% price reduction on fruits, vegetables, nuts and whole grains was estimated to prevent 19 600 CMD deaths/year, including 2.6% (95% UI 2.4% to 2.8%) of all CMD deaths among SNAP participants, 2.7% (95% UI 2.4% to 3.0%) among SNAP-eligible non-participants and 2.6% (95% UI 2.4% to 2.8%) among SNAP-ineligible non-participants. Adding a national 10% tax on sugar-sweetened beverages (SSBs) and processed meats would prevent a total of 33 700 CMD deaths/year, including 5.9% (95% UI 5.4% to 7.4%) of all CMD deaths among SNAP participants, 4.8% (95% UI 4.4% to 5.2%) among SNAP-eligible non-participants and 4.1% (95% UI 3.8% to 4.5%) among SNAP-ineligible non-participants. Adding a SNAP-targeted 30% subsidy for the same healthy foods would offer the largest reductions in both CMD mortality and disparities.

Conclusion National subsidies for healthy foods and taxes on SSBs and processed meats would each reduce CMD mortality; taxes would also reduce CMD mortality more steeply for SNAP participants than for non-participants.