Labour's deputy leader has revealed how he dramatically lost weight and sent his Type 2 diabetes into "remission" by cutting sugar and taking up exercise.
Tom Watson said he considered himself "the perfect poster boy to get an ageing population exercising again" after turning 50 last year prompted him to transform his lifestyle.
The politician said he has lost more than seven stone (45kg) since, having joined "generation active after a 30-year love affair with beer and curries".
Mr Watson's milestone 50th birthday led him to re-evaluate his life while researching the Labour Party had made him realise "one of the most important ingredients for political success is, quite simply, staying alive", he said.
Addressing the ukactive summit in central London, Mr Watson said: "People often tell me I'm a political survivor, but you can't be a political survivor unless you survive physically.
"After 32 years as an MP, and in his sixties, Jeremy Corbyn found himself and his ideas perfectly placed to take over the Labour Party.
"Something that might never have happened had he not been a tee-total drinker, changed his exercise habits with regular cycling and jogging."
'Former sugar addict'
Mr Watson, who was 22 stone at his heaviest point, began regularly exercising, cycling, walking 10,000 steps a day, boxing and weightlifting.
"Since last summer, because of that, I've lost 99 pounds in weight," he said.
Diet changes also led Mr Watson's Type 2 diabetes, diagnosed a few years ago, to be sent into remission.
He told the conference: "I'm pleased and very, very relieved to say that thanks to a quite radical change of diet and behaviour, not just exercising more but eradicating ultra processed food, fast food, starchy carbs and refined sugar, pretty much entirely, my own Type 2 diabetes is in remission.
"I'm no longer taking medication for it, and I feel absolutely fantastic."
He added: "What I know now that I didn't know when I was first diagnosed is that Type 2 diabetes can be prevented, but I am living proof that it can also be put into remission."
Mr Watson earlier told GMB that he considers himself "a former sugar addict" and stressed the importance of changing diet.
He said: "I realised you cannot do it on day one. When guys get really overweight they decide to attack it. The first thing they do is join a gym and they never sort their nutrition out.
"I would say to people if you don't sort your nutrition out there is virtually no point in doing exercise."
He added: "People do get addicted to sugar and I think that is one of the reasons today we are looking at a huge crisis of people being overweight and obese in this country."