Regulation of the immune system by biodiversity from the natural environment: An ecosystem service essential to health

Epidemiological studies suggest that living close to the natural environment is associated with long-term health benefits including reduced death rates, reduced cardiovascular disease, and reduced psychiatric problems. This is often attributed to psychological mechanisms, boosted by exercise, social interactions, and sunlight. Compared with urban environments, exposure to green spaces does indeed trigger rapid psychological, physiological, and endocrinological effects. However, there is little evidence that these rapid transient effects cause long-term health benefits or even that they are a specific property of natural environments. Meanwhile, the illnesses that are increasing in high-income countries are…

• NB
  NIHR Biomedical Research Centre, Royal Marsden NHS Foundation Trust/Institute of Cancer Research
• UC
  University College London
• NI
  National Institutes of Health