Almost four in 10 Britons volunteer, with the vast majority saying it benefits their mental health and acts as an antidote to loneliness, according to a survey of more than 10,000 people.

The survey, conducted by YouGov on behalf of the National Council for Voluntary Organisations (NCVO), involved 10,103 people aged over 18, the largest poll on the subject in more than a decade.

Of the respondents 77% said volunteering had improved their mental health, with just over half (53%) saying it had improved their physical health.

Young people were most likely to say volunteering had helped combat isolation, with 77% of 18- to 24-year-olds agreeing with this, compared with 68% of all ages and 76% of 25– to 34-year-olds.

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“There is an emerging body of evidence that suggests volunteering can improve your mental health and the language I have read is that it can help with depression, life satisfaction and wellbeing,” said Karl Wilding, NCVO’s policy and volunteering director.

“Broadly speaking, it helps as it is a social activity, and when you are doing things with others and groups that conviviality and connectedness is important,” he said, adding that it was most beneficial to people who didn’t have a partner or a job.

A 2017 study into Wildlife Trust volunteers found more than half those who started out with low mental health had improved after 12 weeks.

The NCVO survey found that 69% of respondents had volunteered at some point in their life, 38% having done so in the past year. Extrapolated over the entire adult population, this means more than 20 million people had given of their time at some point in the year.

Older people were more likely to volunteer than younger people, and fully 90% of volunteers said they felt their contribution had made a difference.

Wilding said that in the NCVO’s own research the one thing which surprised him about the findings was that a higher number of 18- to 24-year-olds found volunteering a good way of combatting isolation.

“For me, that is at the heart of what do we do next. Essentially, if you have a cohort of the population who people feel concerned about in terms of connectedness … that strikes me as a real solution.”

Colette Lane, 45, said volunteering had brought purpose back to her life after a spell of mental illness had forced her to stop teaching. She started with local groups and now volunteers with the Surrey and Borders mental health trust, counselling people who have suicidal thoughts.

“Volunteering gave me a purpose back to my life, gave me my identity again and made me feel part of the community when I was feeling isolated,” she said. “It made me feel so proud that my son had a mum now who was keeping herself well and working. I am not well all the time, but now I can say I have the skills and support to help me get through those times.”

Other findings in the NCVO report include indications that people from middle class backgrounds were nearly 50% more likely to have volunteered in the last 12 months than those from working class backgrounds (44% compared with 30%).

Facebook Twitter Pinterest Young people were most likely to say volunteering had helped combat isolation, the survey found. Photograph: Hero Images/Getty Images

“Those from lower socioeconomic groups are more likely to say they have never been involved in volunteering, and those who have are less likely to be in certain leadership or representative roles, like being a trustee. Research on volunteering, and on participation more broadly, consistently indicates that inequalities of resources and power means that some people are more likely to be excluded from certain activities,” the report notes.

The poll also found 74% of people agreed that volunteering had given them more confidence, with the figure rising to 84% among 18- to 24-year-olds. In addition, 71% said they had gained new skills and experience, rising to 85% among 18- to 24-year-olds. And 96% said they were satisfied with their experience and 69% said they would recommend it to others.

Sir Stuart Etherington, chief executive of the NCVO, said: “Volunteering can be truly transformative for people’s lives. It reduces isolation, improves confidence, provides new experiences, improves employment prospects and fundamentally it’s deeply rewarding. But sadly, those who stand to benefit the most from volunteering are less likely to be involved.”

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