He's 70 years old, relies on a pacemaker and has suffered a series of health scares. And four years ago, Sir Elton John himself admitted that his workaholic lifestyle and endless worldwide touring were "killing him".
"I know I'm addicted to playing," the veteran singer said. "I'm addicted to working. I'm addicted to touring. I'm addicted to everything. I can't have one bunch of flowers. I can't do one show. That's part of my nature."
But he added: "You know, I'm fed up with it. The travelling is killing me. I can't do it any more. I've never taken enough time to smell the roses."
Last night, it seemed he was proven right after it emerged he had been rushed to intensive care in yet another health scare; this time suffering from an infection.
Daily Mail revealed that his illness was much more serious than first thought with the singer suffering a "rare and potentially deadly" bacterial infection that left him in intensive care for two days and requiring multiple surgeries.
Sir Elton, who was taken ill on a flight home from his recent South American tour, has been forced to cancel two months' worth of concerts in order to recover.
But the question on the lips of his legions of fans is simple: Why hasn't Sir Elton, the father of two young sons, cut back on his punishing work schedule?
After all, he has spoken many times of his desire to spend more time with his husband David Furnish and their children. As early as 2013, he said: "The time has come in my life when I will definitely cut back on shows so I have more time with my family. That's a conscious decision."
Then, in 2016, he spoke again about cutting back, saying: "I'm hurtling towards 70 and I've made a promise to David and to my sons that I really don't want to be schlepping around the world at 72.
"I don't want to do tours any more that take me away from my children."
Despite these words, he is still going and in the face of his increasingly frequent health issues.
It's not as if he needs the money. Sir Elton has an estimated fortune of £280 million ($517m) plus a string of luxurious homes in Atlanta, London, Windsor, Los Angeles and Nice.
So why keep up a workload more intense than stars half his age?
Despite disappointing album sales, Sir Elton has committed to a gruelling worldwide tour this year; planning to play in Australia in September before zig-zagging across Europe and finishing up in Moscow in December.
At the same time, he is working on his long-awaited autobiography, detailing his difficult struggles with bulimia and drug addiction. (And what a treat the book is likely to be, for Sir Elton has a notoriously short fuse and a habit of picking fights with celebrities.)
On top of that, he must find time to write the music for an upcoming Broadway musical based on the film The Devil Wears Prada and is also contemplating an exhibition of his famous stage costumes.
His work ethic is surely admirable and his spokesman insists he is simply the same "tireless performer" he's always been and "has every intention of keeping it up".
But what other artist of his calibre would consider performing, as he did this year, in Las Vegas on New Year's Eve and New Year's Day?
You wouldn't catch his old friends Mick Jagger or Rod Stewart ringing in the New Year with a bunch of paying punters. A loving husband and father, Sir Elton must envy the ample family time that his husband carves out with his young sons.
The couple's boys Zachary, 6, and Elijah, 4, live with Furnish at Sir Elton's palatial home in Windsor during term-time.
The children, born via a professional surrogate when Elton was well into his 60s, also have a team of nannies and staff on hand.
But Sir Elton, the man they know as "Daddy", is generally based in Los Angeles, thousands of miles away from the main family home.
From there, he takes his private plane to tour venues all over the world.
But while Sir Elton is often busy working, Furnish, who the children refer to as "Papa", is frequently seen enjoying happy holidays with the boys.
For instance, while Sir Elton was performing in Vegas at New Year, Furnish and the children spent the school Christmas break relaxing and having fun on a skiing holiday in the Alps.
At the end of March, Sir Elton had travelled alone by private jet to South America to perform another string of gigs. By the time the exhausted star fell ill on April 10, on a flight to the UK from Chile, his family were on their way back from another holiday, in Furnish's native Canada.
They had enjoyed an outing to watch the Toronto Blue Jays' first game of the baseball season, followed by another skiing trip to Aspen, Colorado; again without the singer.
Furnish, who worked as an advertising executive before he met Sir Elton, showed off various holiday snaps on Instagram and proudly posted videos of Zachary and Elijah on the slopes.
It seems that Sir Elton was not able to join them. The last time, in fact, that he and Furnish were seen in public together was a month ago, at an event in Los Angeles to mark his 70th birthday.
Sir Elton's decision to keep touring may, of course, be driven by his determination to lift his flagging music sales.
The massive worldwide tour Elton is in the middle of (a major commitment that will inevitably see him missing out on yet more time with his family) is to promote his last album, Wonderful Crazy Night.
The album, which came out in February 2016, charted at a respectable No 6 in the UK, but spent a mere five weeks in the Top 100.
The story was similar in the US, where it charted at No 8 and spent only four weeks on the chart.
Even more disappointingly, official records show that it has not yet reached platinum, gold or even silver sales, making it his first studio album to do so poorly since Empty Sky flopped in 1969.
To be a silver album in the UK, you need to sell 60,000 copies; for the US it's 500,000.
Sir Elton, to be fair, has been realistic.
"I follow the charts," he said. "I know everything about the business. I know where I stand as far as selling albums. I'm not going to sell a million albums. I'm not expecting to."
But even the current tour has been a far cry from those of his heyday. As well as big arenas, he has played in modest venues.
In June, he will be in Scotland to play at the Excelsior football stadium in Airdrie, which has a capacity of just 10,000.
Meanwhile, even before this latest serious health scare, it was becoming clear that the touring was taking is toll.
In 1999, Sir Elton had to have a heart pacemaker fitted to deal with an irregular heartbeat, flying to London from his holiday home in the South of France to undergo the operation at the private Wellington hospital.
At the time he had been due to sing at the wedding of Victoria and David Beckham, but had collapsed on board a private plane that was set to take him to the event in Ireland.
In 2009, he was hospitalised for E.coli, a bacterial infection, combined with the flu.
In 2013, he was nearly killed by an undiagnosed abscess on his appendix.
And he fell ill again over Christmas 2016, postponing a show in Dubai in December citing "gastric flu". Organisers later said that a planned reschedule on January 20 was also impossible because he was still not well.
"Though not of a seriously threatening nature, he has been advised by his doctors to schedule a medical procedure to treat his condition immediately," they said.
Of late, his own mortality seems to have been on Sir Elton's mind.
After David Bowie's death he commented, somewhat morbidly, that: "The best thing to happen to your records is for you to die. Death is very popular.
"Obviously, no one wanted David to die, but it's astonishing how many records he's sold since. Something like two million in two weeks. And that's CDs."
Since then, the singer has been hit hard by the deaths of two close friends.
He was deeply upset by George Michael's death on Christmas Day, having been among those who had tried to reach the singer in his later years as he struggled with depression and drug abuse.
He also spoke of his deep sadness at losing his close friend, football manager Graham Taylor, whose funeral he was unable to attend because he was touring.
Now, it is Furnish on whom Sir Elton leans. Furnish is in charge of Sir Elton's career, including masterminding his work schedule.
Many of his oldest staff, including his lawyer, valet, PR and hairdresser, departed in 2015, and, sadly, he is not on speaking terms with his elderly mother Sheila, 90.
Their rift centres on her description of Furnish as: "That thing you married."
The question now is what will Sir Elton do next and how will his deteriorating health fit in with his endless money-spinning plans?