Many people seem to agree that spending time in nature is good for them. Unfortunately, until the 1980s, the proof was primarily anecdotal. However, more recent research measures how nature physically affects us versus how it psychologically impacts us.
In the 1980s, Japan began studies to determine if people spending time in nature provided any measurable benefits. The researchers focused on how nature affected people physically and mentally. They measured people’s blood pressure, stress level measured by cortisol and heart rate variability (more variable is better). They measured before and after forest walks and discovered that all measures improved for most people.
In addition, the researchers discovered that humans have a particular response when exposed to phytoncides, which are aerosols created by trees to protect themselves. Our bodies make a special white blood cell called a natural killer or NK-cell, which roams the body looking for stressed cells that could turn cancerous and destroy them as a preventative measure.
