How much cancer can be prevented? 90 percent, or a third?
One view says 90% of cancer is preventable; the WHO says 30 to 50%. Both rest on real research. Why they differ, and what Australia has already prevented.


Loneliness raises the risk of dying early about as much as other major health risks, yet a GP visit usually ends with a script for a pill. England now pays people to write a different kind of prescription: a choir, a garden group, a club. Australia already built one of the best things to prescribe, the men's shed. The missing piece is the hand that joins the two.
This is a thought experiment with real parts. Each piece already works somewhere. The question is why they don't work together everywhere.
Picture a GP visit that ends differently. A retired man comes in with poor sleep and a low mood. He lost his wife last year and hasn't left the house much since. The GP writes a note, and by the end of the week someone from the practice has rung him, asked what he used to enjoy, and walked him through the door of the local men's shed. Six months on, he's there three mornings a week, fixing bikes for the primary school.
Nothing in that story is new medicine. It treats loneliness as the health risk it is (see Is loneliness really as bad for your health as smoking?) and answers it with people instead of pills.
The idea is called social prescribing: a doctor or nurse refers a patient to something non-medical in the community, such as art classes, cycling lessons, museum visits, volunteering or a befriending service (Wikipedia, 2026a). One UK commission estimated in 2015 that about one GP consultation in five was for a social problem, not a medical one (Wikipedia, 2026a).
The key role is the link worker. A link worker sits with the patient, works out what matters to them, and connects them to local groups. England made the role part of ordinary general practice: from 2019/20 the NHS funded primary care networks to employ social prescribing link workers (Wikipedia, 2026b).
It came from grief turned into policy. MP Jo Cox set up a commission on loneliness shortly before she was killed in 2016. Colleagues from both major parties finished its work, and in January 2018 Prime Minister Theresa May accepted its recommendations and gave a minister responsibility for loneliness. The first was Tracey Crouch. In October 2018 the UK became the first country to publish a national loneliness strategy, with commitments from nine government departments, including encouraging GPs to refer lonely patients to local groups (Wikipedia, 2026c).
Japan followed. In February 2021, as its suicide rate rose during the COVID-19 pandemic, the government appointed Tetsushi Sakamoto as its first Minister of Loneliness (Wikipedia, 2026d, 2026e).
The honest answer: promising, and not yet proven.
| What was tested | What researchers found |
|---|---|
| 15 UK social prescribing programmes (2017 review) | Most reported good results, but all were small and at high risk of bias. The evidence can't yet judge success or value for money (Bickerdike et al., 2017). |
| 118 UK reports on link workers (2020 review) | Link workers help people build trust, belonging and practical support, which gives them the confidence to manage their own wellbeing (Tierney et al., 2020). |
| Group singing for 258 people aged 60+ (randomised trial) | Better mental health-related quality of life at six months, less anxiety and depression at three months, and slightly more cost-effective than usual activities (Coulton et al., 2015). |
| Gardening (2017 meta-analysis) | Gardening benefits health across a range of outcomes (Soga et al., 2017). |
| 52 studies of men's sheds (2022 review) | Evidence of benefits for self-rated health, social isolation and wellbeing; stronger long-term studies still needed (Foettinger et al., 2022). |
Two points stop that table being misread. First, "not proven" isn't "doesn't work". Most of these programmes are small and local, and the reviews ask for bigger, longer, controlled studies, not for the programmes to stop.
Second, a referral only helps someone who can take it up. Researchers found that the same social conditions that harm people's health also make it harder to join in (Gibson et al., 2021). Handing out referrals alone won't close the gap between rich and poor areas (Moscrop, 2023). Link workers need time, and groups need to be close and cheap.
In 1993 Maxine Chaseling was running activities for older people at The Heritage Club in Goolwa, South Australia. Her father had a heart attack, couldn't work, and sank into depression. The one thing that still gave him purpose was his shed. She noticed the men at the club looked just as lost, so on 3 March 1993 she opened a shed for them. It worked, and the idea spread to Langhorne Creek, then across the country (Wikipedia, 2026f). "I struck the match," she said later, "but fortunately it was the right time and the primary health strategy was simple and doable in any community."
The Australian Men's Shed Association formed in 2007. It now counts more than 1,300 sheds and more than 60,000 members, and points out, proudly, that Australia has more men's sheds than McDonald's restaurants. More than 2,500 sheds now run in 12 countries (Australian Men's Shed Association, 2026).
The shed movement's slogan explains why it works where a support group might not. It's "Shoulder to Shoulder", short for "Men don't talk face to face, they talk shoulder to shoulder" (Wikipedia, 2026f).
That's Australian mateship in one line. Many blokes won't sit in a circle and share their feelings. Put them side by side over a workbench, with a job to finish and a cuppa going cold, and the talk comes on its own: about a diagnosis, a divorce, a son who won't ring. Nobody calls it therapy. The work gives people a reason to turn up, and turning up again and again, beside the same faces, is what builds trust. The shed didn't need a trial to find that out. A woman watched her dad and trusted what she saw.
England built the link but had to find things to link to. Australia grew the things to link to, from the ground up, without the link. Now the two are starting to meet. Victoria's Royal Commission into its mental health system recommended a social prescribing trial in each region, aimed especially at older Victorians, and trials are planned in six local services, from Frankston to Geelong-Queenscliffe (Wikipedia, 2026a).
What slows it is how health spending is counted. A pill has a price and a trial. A choir has a volunteer conductor and a hall that needs a new roof. When only one of those counts as health care, the system keeps buying the pill.
England pays people to make the introduction. In Goolwa, one woman did it because she loved her dad. Either way, the prescription is the same: somewhere to go, something to do, and people beside you.
One view says 90% of cancer is preventable; the WHO says 30 to 50%. Both rest on real research. Why they differ, and what Australia has already prevented.

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