Many analyses and reviews have concluded that, at least for some individuals in some circumstances, exposure to nature can lead to improvements in multiple mental and physical health parameters and that this applies for both contemplative and adventurous activities (1–15). Over at least the past 4 decades, countries have trialed a wide range of public health programs aimed to increase public participation in outdoor activities, including visits to parks (14–18). At the same time, however, social and technological changes have created opposing pressures: education, work, and lifestyles in developed nations have become increasingly urbanized and indoors (19). Perhaps, as a result, these public health programs have achieved only limited success to date. This issue is important in public health, since many developed nations are now experiencing increasing social and economic costs from depression, dementia, obesity, and diabetes (10–13, 20–22). These diseases are distinct, but correlated across individuals, and known jointly as chronic disease syndrome (CDS). They are driven partly by genetics (23), but largely by lifestyle (10–13). Older individuals live longer, in poor health, but children are also affected (24). Costs include treatments and healthcare, lost productivity, paid and unpaid carers, and decreased quality of life (QOL)(6, 20–22, 25). In total, these costs may be~ 10% GDP for nations with aging populations and high per capita healthcare expenditure (6, 20–22, 25).

If we could design health programs or interventions that use outdoor nature-based activities to prevent or treat CDS cheaply and effectively, then that would provide an opportunity to alleviate substantial individual suffering and to overcome a major and growing budgetary problem for national governments (26). A wide range of such programs do exist, under names such as ecotherapies (2), adventure therapies (27), outdoor adventure interventions (27), ecopsychosocial interventions (13), lifestyle therapies (28), and green prescriptions (18, 29, 30), but currently, at rather small scale in global terms. We refer to them here, in aggregate, as nature, eco, and adventure therapies (NEATs). Here, we identify some obstacles to their success and propose research and policy changes for more effective implementation.