Researchers examined the link between extreme heat and mortality in 1,300 municipalities in the Île-de-France region over a 25-year period, taking into account the density and degree of urbanization: housing density, the extent of green spaces, soil sealing (i.e., concretization), and so on. The results show a significant reduction in the risk of heat-related deaths in municipalities with less artificial development, less soil sealing, and more trees, particularly in Paris and the inner suburbs. This study aligns with previous scientific research. Environmental interventions are therefore likely to reduce heat-related health risks, particularly by reducing the population’s exposure to heat.