Short visits to nature in cities are associated with measurable reductions in physiological stress, supported by experimental and observational research. Studies show brief exposure can lower cortisol levels, reduce heart rate and blood pressure, and change brain activity linked to rumination. These effects are most reliably documented for short, repeatable exposures rather than single, one-off events.
Evidence from experiments
A randomized study by Gregory Bratman at Stanford University compared 50-minute walks in natural versus urban settings and found reduced self-reported rumination alongside decreased activity in the subgenual prefrontal cortex, a brain region tied to depressive thought patterns. Qing Li at Nippon Medical School has reported that forest bathing interventions increase natural killer cell activity and reduce stress hormones, indicating immune as well as endocrine effects. A systematic review and meta-analysis by Caoimhe Twohig-Bennett and Andy Jones at the University of East Anglia synthesized multiple studies and concluded that contact with green space is associated with improvements in mental wellbeing and stress-related outcomes. The World Health Organization recognizes urban green space as a contributor to mental health and recommends access as part of public health planning.
Mechanisms and consequences
Several overlapping mechanisms explain why brief nature contact lowers physiological stress. One pathway is reduced sympathetic nervous system activation resulting in lower heart rate and blood pressure. Another is attentional restoration, where natural environments allow cognitive recovery and lower rumination. Increased incidental physical activity and opportunities for social interaction also mediate benefits, as shown in research by Frances E. Kuo at the University of Illinois Urbana-Champaign linking green space to reduced aggression and improved mental health via social cohesion.
Consequences extend beyond individual physiology to population health and urban design. Short-term reductions in stress may accumulate to lower long-term cardiovascular risk if exposures are regular. Access inequality matters: neighborhoods with fewer or lower-quality green spaces show higher stress burdens, producing territorial and environmental justice concerns. Cultural values shape how people use and benefit from natural areas; for some communities, social and spiritual meanings of green spaces amplify restorative effects. Urban planners and public health practitioners can therefore improve resilience by prioritizing equitable, culturally appropriate green space in city design.