Background: Dietary guidelines play a key role in promoting health and preventing chronic diseases. The Nordic Nutrition Recommendations (NNR) 2023 provide updated recommendations for healthy eating relevant for the Nordic and Baltic countries, but the potential Objectives: This study aimed to project the population health benefits, specifically, potential gains in life expectancy in Nordic and Baltic countries resulting from long-term dietary changes from current dietary patterns within each country to NNR2023. Methods: For this population-based mathematical model, using the Food4HealthyLife 2.0 calculator, data were obtained from metaanalyses on associations between each food group and mortality, and background mortality data were derived from the Global Burden of Disease study. Standard life-table methods were used, accounting for the correlation between 14 food groups and the anticipated time delay between dietary changes and health effects. Results: For 40-y-old females and males, projected life expectancy gains were from 1.8 and 2.1 yin Finland to 3.4 and 4.1 y, respectively, in Lithuania, changing to feasible NNR2023. Correspondingly, when changing to full-potential NNR2023, gains ranged from 4.4 and 5.0 y in Finland to 6.1 and 7.3 y, respectively, in Lithuania. The largest gains in life expectancy were linked to consuming more legumes (18%), nuts Conclusions: Adopting dietary patterns in line with the NNR2023 is associated with considerable gains in life expectancy in the Nordic and Baltic countries. The study contributes to the evidence base to support policy measures to achieve NNR2023.