Population health in the anthropocene: Gains, losses and emerging trends

The health of human populations, measured by life expectancy, is at an historical high. Will this continue – or are we reaching Peak Health? The gains have been unequally shared, but the gap between low-income and high-income countries is narrowing. Meanwhile, there is clear evidence that levels of wealth per se do not predetermine population health, and that today’s depleting and disrupting of Earth’s biophysical, life-supporting, systems will sooner or later translate into a substantial decline in population health. It is likely, for example, that current trends in the late-stage Anthropocene, including continued population growth, will cause a crisis in food production, affordability and hence substantial health losses. There is a widespread misplaced assumption, reinforced by today’s pervasive neoliberalism, that the determinants of health reside largely in individual behaviours, genes and access to healthcare. But at population level and over the longer term the determinants of health and survival lie with nature’s life-supporting systems. Ultimately, without trade and aid, the profile of a population’s health reflects the underlying ecological, human–environment coupled, relationship. The adverse health impacts of climate change illustrate well the present and likely future health consequences of humankind’s overloading of nature’s capacities. Human-generated greenhouse gases are increasing the atmosphere’s capture of heat-energy; that heat accumulates, particularly in the oceans; and Earth is warming. A major moral (and geopolitically enlightened) task is for international assistance with social and economic development in poorer countries. That may seem to clash with the now-urgent need to curtail global non-renewable energy use and constrain ongoing exploitation of forests, aquifers, soils and coastal ecosystems, and nitrogenous fertiliser use. Yet integrating these two agendas, potentially mutually reinforcing, is technically possible. This would assist transition to a world of environmentally sustainable living, in which the universal norm is to remain healthy and survive into comfortable older age.