A major scheme helping people in England connect with nature led to big improvements in mental health, a report has found.

The prescribing of activities in nature to tackle mental ill health has benefited thousands of people across England, a government-backed project has shown.

More than 8,000 people were helped to take part in activities including nature walks, community gardening, tree planting and wild swimming. It is thought to be the largest such project in the world so far.

The results showed that after taking part in the schemes, people’s feelings of happiness and of life being worthwhile jumped to near national averages, while levels of anxiety fell significantly. The project also found the cost of a green prescription was about £500, making it cost-effective compared with other treatments. Cognitive behavioural therapy costs about £1,000 for 10 sessions.

The seven green prescribing pilot projects began in 2020 with £5.7m of government funding. GPs, mental health teams and social workers referred those in need to the schemes.

Prof Ruth Garside at the University of Exeter, an author of a report on the scheme, said: “Our findings [show] ‘green social prescribing’ is an effective way of supporting people with their mental health. But this is just the beginning. There must be an ongoing commitment from policymakers.”

“There is an awful lot of demand, both from health services and from a lot of people whose needs are not being met,” said Dr Becca Lovell, also at the University of Exeter. Mental health services have been a particularly stretched part of the National Health Service. The seven pilots are expected to get a new round of funding to work on expanding their reach.

“After the group I feel joyful, happy, calm,” said a participant in one of the schemes. “I have a sense of achievement and I feel my wellbeing increasing.”

Another participant, whose mental ill health is related to trauma, said: “It works better than medication for me. It works better than CBT for me. I have my counselling and that is really valuable, but this is on a par with that.”

The participants were assessed before and after taking part in the green prescribing schemes. Their average happiness scores went from 5.3 out of 10 to 7.5 and feelings that life was worthwhile rose from 4.7 to 6.8. Reported levels of anxiety fell from 4.8 to 3.4. One of the sites also used a medical scale to assess anxiety and depression and found a statistically significant improvement in both.

Dr Marion Steiner, a GP in Bristol and part of the pilot project in the west country, said: “Connecting with nature is a lifelong resource with proven benefits for mental and physical health. It can cut through generations of adverse life events.

“But many of the patients I treat can’t currently access nature in this way due to a range of personal, social, and cultural barriers. That’s why green social prescribing is so important. This project has the potential to reduce a range of prescribing and treatment costs for the NHS, as well as addressing many health needs and lowering the risk of several diseases, from diabetes to depression.”

The green prescribing sites were in Humberside, South Yorkshire, Derbyshire, Nottinghamshire, Manchester, Surrey and the west country. They reached a broad range of people compared with earlier social prescribing schemes, with 21% from ethnic minority populations and 57% from economically deprived areas.