The death of 19-year-old Stephen Churchill, Britain's first known teenager to die of nv-CJD, was most likely caused by his diet, Dr James Ironside, of the National CJD Surveillance Unit in Edinburgh, told the Wiltshire coroner.
The disease reduced Mr Churchill from a healthy, active student to a tragic and confused wheelchair patient.
The coroner, David Masters, recorded a verdict of misadventure - the same verdict as a number of other coroners who have investigated deaths from nv-CJD.
Mr Churchill's mother, Dot, described how in 1994 he had a car crash in which he could not recollect how he came to be on the wrong side of the road. He became more confused, withdrawn and quiet, she said.
Previously he had enjoyed a healthy appetite, but avoided convenience foods, though he sometimes ate burgers and liked sausages.
The family has campaigned for almost four years for an inquest into his death, which occurred in May 1995 but was recorded as "natural causes". The inquest was ordered by the Home Secretary, Jack Straw.
Afterwards, Mr Churchill's father, David, said: "It is quite a terrifying thought that one single meal could create such a dreadful disease in one person.
"This has put into place the last piece of the jigsaw. We feel the verdict is appropriate."