Biodiverse green spaces: a prescription for global urban health

The world is urbanizing and chronic health conditions associated with urban living are on the rise. There is mounting evidence that people with a diverse microbiome (bacteria that inhabit the human body) or who interact with green spaces enjoy better health. However, studies have yet to directly examine how biodiverse urban green spaces (BUGS) might modify the human microbiome and reduce chronic disease. Here we highlight the potential for green spaces to improve health by exposing people to environmental microorganisms that diversify human microbiomes and help regulate immune function. We present four international perspectives (from Australia, China, India, and the UK) on the major challenges and benefits of using BUGS to alleviate health burdens. We propose solutions to these challenges and outline studies that can test the connections between BUGS, immune function, and human health and provide the evidence base for effective BUGS design and use. If further studies reinforce this hypothesis, then BUGS may become a viable tool to stem the global burden of urban-associated chronic diseases.