A 62-year-old former police officer in England is to sue his local trust for denying him funds for bariatric bypass surgery.
The North Staffordshire Primary Care Trust says the old man is not fat enough to qualify for the funding.
Tom Condliff weighs 22 stone, giving him a Body Mass Index (BMI) of 43. He needs a BMI of at least 50 for NHS North Staffordshire to fund a gastric bypass.
But different primary care trusts have different norms. He might have become eligible for assistance somewhere else, say, if he had been living less than a mile away in Stoke-on-Trent.
According to the National Institute of Clinical Excellence rules, a BMI of 35 is high enough to trigger treatment, as long as the patient has other illnesses besides obesity.
He is actually taking 28 different drugs to try to keep his ailments in check.
His lawyers say he has become obese precisely because of the drugs he is forced to take.
His long-standing diabetes has swung out of control in the past two years as he has gained 66lbs. He is 6ft 2ins tall and originally weighed only 15 stone.
Now confined to a wheelchair, Condliff had served as a medic with the Royal Navy before joining the police and was also the director of a medical charity for spinal injuries.
He said: "This is not a question of me wanting this operation - in fact it's something I'd rather avoid as it's very unpleasant and involves removing part of my intestine and stomach.
"But put bluntly, I need it to save my life and if I don't get it, doctors say my kidneys will quickly fail and then I'll have three years to live.
"It's not about vanity or gluttony either. I'm not a vain man and I've always been fit and active, but my weight has ballooned purely because of the drugs I need for all my illnesses."
His lawyer, Oliver Wright, said: "This will be the first case of its kind before the High Court.
"Our judicial review of the funding refusal is based on the fact he has been treated unfairly under the Human Rights Act. Each case has its own merit and while it won't open the floodgates if he wins, it will make it easier for others in the same position."
If he wins, the surgery will be carried out using keyhole techniques at the University Hospital of North Staffordshire as medics say he is now too ill to withstand a conventional operation.
The surgery costs £9,000 but Mr Condliff has been told by consultants that the benefits will be so great he will no longer need drugs, hospital appointments or a wheelchair, all of which come with a price tag of £20,000 a year.
If he doesn't get the surgery and then needs kidney dialysis, the cost of his care will double. Thus the government stands to lose a lot more if funding for gastric surgery is denied - such is the argument.
But a spokesman for NHS North Staffordshire said: "We understand patients find it disappointing when they cannot simply have any treatment they would like.
"These are difficult decisions and we aim to do the best for our patient population with the limited funds we have."