"It's well known that getting outdoors in nature can be good for people's health and wellbeing but until now we've not been able to say how much is enough," said lead researcher Mat White of the University of Exeter Medical School in Britain.
"The majority of nature visits in this research took place within just two miles of home so even visiting local urban green spaces seems to be a good thing," White said.
However, no such benefits were found for people who visited natural settings such as town parks, woodlands, country parks and beaches for less than 120 minutes a week.
The study used data from nearly 20,000 people in England and found that it didn't matter whether the 120 minutes was achieved in a single visit or over several shorter visits.
It also found that the 120 minute threshold applied to both men and women, to older and younger adults, across different occupational and ethnic groups, among those living in both rich and poor areas, and even among people with long term illnesses or disabilities.
"There are many reasons why spending time in nature may be good for health and wellbeing, including getting perspective on life circumstances, reducing stress, and enjoying quality time with friends and family," said study co-author Terry Hartig of Uppsala University in Sweden.
"The current findings offer valuable support to health practitioners in making recommendations about spending time in nature to promote basic health and wellbeing," Hartig said.