I argue for the need of a new concept of environment for human health studies. After showing the theoretical shortcomings of the fashionable concept of exposome, I borrow from studies in philosophy of biology the idea that the biological environment is a constructed niche. In this view, the environment is always determined (at least partly) by the properties and activities of its reference entity (ontological dependence). Besides, it includes elements that depend on the problem addressed by scientists (epistemological dependence). I claim that, to be more relevant and operational, the environment in health studies should be conceived as a pathogenic niche, epistemologically shaped by the physicians' questions, and ontologically determined by the population that inhabits it. Finally, I ask how our proposal could be translated into tools for scientific practice, and I show its empowering nature for physicians, scientists, but also for politicians and lay people.