While global warming and climate change associated with increasing carbon dioxide are widely seen to be one of the most serious worldwide dangers to population health, little is known regarding “how” country alters the linkage between increasing CO2 emissions and population health outcomes. Current literature on the health effects of CO2 emissions recommends various factors that may establish a more robust link, including health expenditure and research and development. Therefore, the purpose of this inquiry is to examine the effectiveness of health expenditure and R&D in improving health outcomes through reducing CO2 emissions. Using data for Saudi Arabia over the period 2000–2018, the dynamic ordinary least squares (DOLS) technique shows that (i) health and R&D expenditures decrease infant mortality and increase life expectancy; (ii) health and R&D expenditures reduce CO2 emissions in all the estimated models; (iii) health and R&D expenditures can improve health outcomes through reducing CO2 emissions; and (iv) health and R&D expenditures have both direct and indirect effect on health outcomes. Policy implications and limitations are also discussed.