A free pint in exchange for a check-up has been suggested by the Duke of Cambridge as a possible way to encourage reluctant men to look after their health.

William appeared to be only half joking when he put forward the idea to help tackle a problem with men who sometimes dismiss changes in their body until it is too late.

His comment came in the grounds of London’s Royal Marsden Hospital when he toured the Man Van, a mobile clinic providing free health checks to men, especially black men who have a higher risk of dying from prostate cancer than other ethnic groups.

William asked what the symptoms of prostate cancer were, after admitting he did not know, and when told changes in toilet habits was one factor he said: “It’s tricky when it’s so subtle.”

He told Fionnuala McCarthy, an advanced nurse practitioner, who this week has been seeing patients in south London, “I have an idea that could go down very badly but it might be quite good – you could offer a free pint.

“I think guys having a pint while you’re having you blood test that would be a great way of doing it.”

Her colleague Dr Masood Moghul, a clinical research fellow who is collecting data from the men seen, said maybe they could look for funding for a coffee machine.

But William replied: “You’re going to have to think a bit imaginatively to get guys in here. It’s a kind of thing they’ll do if there’s a fun thing that goes with it, not too serious.”

The van is visiting workplaces and community hubs, including churches and medical centres and is focused on men of working age who often have worse prostate cancer outcomes than older men, and black men, who have roughly double the risk of developing prostate cancer.

A range of examinations are offered from blood pressure tests to a blood test to check prostate-specific antigen levels which, if high, may indicate that further investigation is required.

The pilot programme will examine whether this care model can improve diagnosis and survival of men in these high-risk groups. If successful, the approach could be rolled out across the NHS.

The innovative pilot project was developed by the Royal Marsden, RM Partners West London Cancer Alliance, and The Institute of Cancer Research, London (ICR), with support from The Royal Marsden Cancer Charity.

William, who is president of the Royal Marsden, one of Europe’s leading cancer hospitals, also watched a cutting-edge procedure to treat patients during his visit to the hospital.