Reducing animal-sourced foods in diets saves a significant share of environmental impacts. Sustainable dietary patterns have proposed large reductions in red meats in particular. Foods with the potential to reduce the environmental impacts of diets are under increasing investigation, and cultured meat, produced by culturing animal cells, could play a key role, especially for diet transitions away from high red meat consumption. In this paper, the inclusion of cultured meat in optimized Danish diets is explored through minimizing climate impact in greenhouse gas emissions measured through Global Warming Potential (GWP) with ±30 %, 60 %, and 90 % stepwise changes from current diets while meeting nutritional requirements; the total consumer diet costs were also assessed. Three optimization models were run, one with a cultured meat diet (all animal-sourced meats are replaced with cultured meat), an omnivore diet (with conventional animal-sourced foods and no cultured meat), and a vegan diet (neither cultured meat nor other animal-sourced foods are allowed). Results revealed that both omnivore diets with and without cultured meat and vegan diets can achieve impact improvements compared to current diets. The greatest GWP reductions can be seen in the cultured meat diet (8.0 Mt CO₂ eq./yr) and vegan diets (9.8 Mt CO₂ eq./yr) with 90 % deviation in both from current diets. These reductions could represent potential Danish national emissions decrease of 21 % and 25 %, respectively, in 2022 impacts. Cultured meat diets resulted in the highest costs (11.58€/day) compared to the current diets (8.05€/day), vegan diets (6.49€/day), and omnivore diets (6.11 €/day). This paper provides key information about diet shifts and the potential of novel foods to reduce carbon emissions compared with the current diets. Although the socio-cultural acceptability and technological readiness of cultured meat, which represent crucial prerequisites to its inclusion in diets, still need to be assessed.