Very seldom does an idea seeded around a pub table prove to be clever, practical or long-lived; most start to wither around last orders and have all but died by the time the hangovers descend.

Rarest of all is the bar-born vision that endures to save lives, raise millions for research and get men all over the world sprouting moustaches and openly discussing the threats to their testicles and prostate glands.

But the Movember phenomenon has done precisely that in the nine years since a pair of Australian friends sat in a Melbourne pub and mulled the rehabilitation of the moustache.

The idea was simplicity itself: grow some lip hair over the course of November to raise some money for men's health charities.

While the original 30 moustache-brothers – or Mo Bros – raised just A$300, they did manage to set the rules for the challenge and come up with a name for the enterprise through the ingenious shunting of the words moustache and November.

The second Movember stunned all those involved by raising the equivalent of £21,600. It also revealed the extent of the shortfall in male cancer funding.

"When we went and approached Prostate Cancer Australia with it, it was the single largest cheque they'd ever received," says Justin Coghlan, one of the original 30 Mo Bros.

"From that point forward, we were all blown away. I would have thought they had a lot more money than that. We assumed it would just be up there with the breast cancer [charities] of the world we'd been involved with through the women in our lives, that it would have equal standing. But it just didn't."

Movember 2005 hit £507,000. The next year, it raised £3.7m, spread internationally and acquired its own slogan: "Changing the face of men's health."

Last year saw 854,000 Mo Bros and supportive Mo Sistas all over the world raise almost £80m.

Coghlan, who still seems astonished by Movember's success, believes its popularity is down to an atavistic male urge.

"I guess every guy wants to know what it's like to grow a moustache. It's for a serious cause, but it's a fun thing to do with your mates and to compete," he says.

Growing – or attempting to grow – a moustache also tends to get men talking about the previously taboo subject of male health. "It's an instant conversation piece and now it's got to a level in some countries – especially in the UK – where I've been walking around in those first five days this year and you just get that nod from people walking down the street, going, 'Yeah, I'm doing it'," he says. "It's a lot of camaraderie and a lot of guys coming together."

More tangibly, says Coghlan, the Movember Foundation is now the largest global funder for prostate cancer research, and the £184m it has raised to date has allowed it to identify 27 types of prostate cancer and genome-map the disease. Equally importantly, it sparked an estimated 1.9bn conversations about Movember and men's health on social media around the world last year, leading more men to think about their health and go to the doctor.

"We had a guy in the UK called Michael email us a week-and-a-half into Movember this year," says Coghlan. "He'd seen us on Facebook, gone and got himself checked and found a lump, which was testicular cancer. He emailed us 10 minutes after his diagnosis, saying, 'Look, you guys have pretty much saved my life. Thanks a lot.' For us, that was really heavy."

Among the 354,000 Britons who have registered for this year's Movember are some who have survived cancer.

Jason Keener, a large goods vehicle instructor from Cheshunt currently sporting a moustache he proudly describes as a "bit Village People-ish", was diagnosed with prostate cancer last year at the age of just 40.

"I thought that only older men got it," he says. "To quote my consultant – bless him – 'You're unique'. I'd rather be unique for an IQ of 150 than being one of the youngest men to be diagnosed in the country."

A year after the surgery that removed the cancer, Keener is employing both his moustache and a charity parachute jump to honour the pledge he made to raise funds and awareness if he survived.

Ben Bowers, another Movember ambassador, is less thrilled with his moustache.

"It's quite bushy but it comes out incredibly blond, so it's very hard to see," he says.

The 33-year-old headhunter, who lost one testicle and then the other to cancer, managed to have a baby with his wife because the disease's return was detected quickly. After three months of intensive chemotherapy to deal with the cancer's spread to his lymph nodes, he was given the all-clear.

Like Keener and Coghlan – and perhaps many of the 2.9 million men and women who have embraced Movember over the last nine years – Bowers believes the phenomenon's success is not hard to fathom.

Peer quickly into the male psyche, he says, and it all makes sense.

"It's fun and it's engaging; it brings people together. It's easy to do – you don't need to go training for it; essentially all you do is stop shaving. A lot of it comes through admiration of people who can grow a moustache – and then there are people who can't, so it builds a bit of banter. Blokes are blokes and they like to gang up together and have a bit of a laugh."