Legendary singer Roy Orbison died due to his addiction to yo-yo dieting, a new TV documentary has claimed.

American pathologist Dr Michael Hunter believes the singer famed for hits such as Pretty Woman and Crying developed an obsession with his weight.

Following the death of his wife and two eldest children, Orbison threw himself into non-stop work.

But away from performing, the star would binge eat on junk food before then forcefully starving himself to lose weight before his next concert tour.

“This cycle of substantial weight gain followed by drastic weight loss would have undoubtedly placed tremendous strain on his heart,” Dr Hunter said.

In the documentary, Autopsy: The Last Hours of… , which is due to be shown in the UK later this year, the pathologist reviews Orbison’s medical records.

After speaking with friends and family, he also discovered how the Only The Lonely singer, ignored a dire warning to curb his unhealthy lifestyle.

Despite undergoing triple heart bypass surgery ten years before his death in December 1988, he quickly went back to his overindulging then fasting schedule.

Dr Hunter added: “This form of dieting, on top of a sudden exercise programme at the age of 52, could have been a step too far.”