Many years ago, Jeff, now 59, had a serious accident at work that left him with permanent injuries. He’s now a volunteer with Sporting Chance, a project that engages older men in the north east in activity and exercise groups, and runs regular bingo sessions.

“Most people who have met me wouldn’t believe that I used to be introverted, especially with regards to my health,” he says. “I was quite shy.”

The change that Jeff has experienced in his life as a result of volunteering is something many of the 30,000 involved with our Volunteering Matters charity have also seen. They do all kinds of volunteering in their community, from befriending elderly and isolated people or supporting families where children are at risk, to giving someone a lift to a hospital appointment.

There is now broad agreement about the positive contribution volunteering can have for people’s health and wellbeing. Recently, for instance, I was cheered to hear delegates at a recent public health conference recognise how volunteering can improve health and wellbeing, including that of people with conditions like dementia. Volunteering helps reduce loneliness, now recognised as a serious health risk, and is one of the community-led approaches that can help improve mental health.

Volunteering has been acknowledged as part of the wider health policy, with the NHS five-year plan identifying a need to encourage community volunteering. Italso has an important role to play in tackling social exclusion, through projects such as lunch clubs for older people, assisted gardening schemes, or young play leaders.

Volunteering can help to provide people with ways out of poverty, by giving them new skills and confidence, and aid social integration. This is of particular value to those who are most excluded from the labour market, such as recent migrants or people with disabilities.

But while the benefits of volunteering are clear, there is worrying evidence that the people who could benefit most from giving their time are precisely those least likely to be involved.

There are many reasons for people not to volunteer. For older people, the barriers can include poor health, poverty, lack of skills, poor transport links, or having caring responsibilities, such as looking after grandchildren. Younger people can be deterred by feeling they don’t have the time to volunteer, or not knowing anyone else who volunteers. Many also think volunteering is just for older people with time on their hands. Volunteering has an image problem – particularly with men and younger people.

Our recent report (pdf) shows that while volunteering can be a way for people to boost their personal and social resources, it also shows that people need those resources in the first place to take part.

We’ve worked in a number of areas, including Hampshire, Greater Manchester, Sheffield and East Sussex, to identify what can be done to give everyone fair access to volunteering opportunities. We’ve worked with councils, the NHS and the voluntary sector to see what can be done locally to encourage people who would usually be least likely to volunteer.

What’s the answer? More should be done to promote the value of volunteering to the particular needs of different groups. There is evidence on why people choose to volunteer, and we need to make better use of that information.

For instance, our own recent survey showed that 95% of young people, aged 13-24, hoped to develop new skills through volunteering, compared to just 32% of volunteers aged over 55. Almost three quarters of young people were keen to gain qualifications through volunteering compared to just 13% of those over 55.Over three quarters of disabled volunteers were keen to develop new skills and nearly two thirds hoped to improve their health and wellbeing through volunteering.

But we’d also like to see everyone involved in organising volunteers offer opportunities based far more on the needs and interests of potential volunteers, rather than on the needs of the organisation managing them.

The Sporting Chance project is one example of how that could work. Launched in 2016 with support from the People’s Postcode Lottery, the project has been successful largely because volunteers and beneficiaries are asked what activities they would like to take part in – and the projects evolves around that, rather than the other way round.

Volunteers don’t just need access to opportunities, they also need continued support if they are to gain the most from their experience, and that, too, should focus on their individual needs.

Local health and social care leaders are starting to recognise the power of volunteering and the importance of diversifying the pool of volunteers. Health Education England, for instance, has a volunteering strategy, on which it consulted in 2017. But support for volunteers can’t be left to the voluntary and community sector. It requires partnerships with local councils and the NHS, with everyone working together on a strategy for local volunteering.

We believe this could break down some of the existing barriers to volunteering – and give everyone a chance to transform their own lives and those of others.

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