After the death of Elvis Presley on August 16. 1977, rampant speculation remains about the cause of the death of the 'King of Rock 'n' Roll'. Presley, born in Mississippi, was found face down on his bathroom floor after falling from his toilet seat, aged just 42.

After years of poor health - exacerbated by junk food and drug abuse - Presley weighed around 350lbs when he died at Graceland. He had spent years indulging in platters of cheeseburgers and had even developed sores on his body from poor hygiene.

Accordingly, an autopsy on the singer gave clues as to what might have caused Presley's death. Pathologists found that he had a four-month-old impacted stool in his bowel, and had been given over 9,000 injections, vials, or pills in the seven months prior to his death.

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Ginger Aiden - Elvis' girlfriend at the time - described finding the singer with his pajamas around his ankles. 21 at the time of his death, she wrote in her autobiography: "His arms lay on the ground, close to his sides, palms facing upward.

"It was clear that, from the moment he landed on the floor, Elvis hadn't moved. I gently turned his face toward me. A hint of air expelled from his nose. The tip of his tongue was clenched between his teeth and his face was blotchy. I gently raised one eyelid. His eye was staring straight ahead and blood red."

Elvis Presley died in August 1977
Elvis Presley died in August 1977

Public curiosity in the situation was piqued after Presley's family sealed the results of the autopsy for 50 years. Dan Warlick, the chief investigator for the Tennessee Office of the State Chief Medical Examiner, attended the autopsy and fueled the theory that Elvis died while straining on the toilet.

"Presley's chronic constipation - the result of years of prescription drug abuse and high-fat, high-cholesterol gorging - brought on what's known as Valsalva's [maneuver]," Warley said. "Put simply, the strain of attempting to defecate compressed the singer's abdominal aorta, shutting down his heart."

Other fans speculated that Presley had died as the result of a drug overdose but when an investigation was reopened in 1994, coroner Joseph Davis poured cold water on the idea.

Elvis Presley and his wife, Priscilla, prepare to leave the hospital with their new daughter, Lisa Marie. Memphis, Tennessee, February 5, 1968.
Elvis Presley and his wife, Priscilla, prepare to leave the hospital with their new daughter, Lisa Marie. Memphis, Tennessee, February 5, 1968.

He said: "The position of Elvis Presley's body was such that he was about to sit down on the commode when the seizure occurred. He pitched forward onto the carpet, his rear in the air, and was dead by the time he hit the floor.

"If it had been a drug overdose, [Elvis] would have slipped into an increasing state of slumber. He would have pulled up his pajama bottoms and crawled to the door to seek help. It takes hours to die from drugs."

The biggest insight into Elvis' death emanated from Forest Tennant - a prominent California physician who reviewed the report while defending Elvis' doctor, Dr. George Nichopoulos. Dr. Nicopoulous was later acquitted of over-prescribing drugs.

As a young man, Elvis had been in very good physical condition partly as a result of practicing martial arts and playing football. But for Mr. Tennant, the full body deterioration of Presley was a clue as to his demise.

Mr. Tennant believes that something other than these external factors was at play, mainly due to complaints made by Presley himself about symptoms. The singer spoke of headaches, eye infections, back pain, insomnia and vertigo at varying points - and was rushed to hospital in 1973 in a semi-coma.

When Presley arrived at the hospital he was found to be suffering from hepatitis, a gastric ulcer, constipation, a distended abdomen as well as jaundice and a swelling of the face.

Elvis Presley sits cheek to cheek wit his bride, the former Priscilla Ann Beaulieu, following their wedding May 1, 1967.
Elvis Presley sits cheek to cheek wit his bride, the former Priscilla Ann Beaulieu, following their wedding May 1, 1967.

He was hospitalized again in 1975 with high blood pressure, high cholesterol and a condition called megacolon, whereby the large intestine becomes distended and can allow toxins to flood the body. He also had at least four near-death overdoses that left him unconscious and in need of resuscitation, and his heart was double the normal size.

And despite having never smoked, he also suffered from emphysema. So what had caused all of these disease processes in his stomach, liver, lungs, heart, spine, eyes and bowel?

Forest claims it all relates back to a serious head injury he got in 1967 that prompted a progressive autoimmune inflammatory disorder.

In his opinion, as shared in a 2013 medical paper, when Elvis tripped over a television cord and knocked himself out on the bathtub, the injury was so severe that it caused brain tissue to dislodge and seep into his blood circulation. There, the body identified the matter as foreign and produced antibodies to destroy it, triggering hypogammaglobulinemia, a disorder of the body's immune system.

At the time, little was understood about auto-immune conditions, but these days they are known to cause most of the symptoms Elvis displayed, from chronic pain, irrational behavior, obesity, and enlarged and diseased organs like the heart and bowels.

In 2016 Garry Rodgers, a retired homicide detective and forensic coroner, told the Huffington Post that with those findings in mind, he would have attributed Elvis' death to a heart attack caused by heart disease and drug use caused by an autoimmune disease which was sparked by a brain injury.

Mr. Tennant said: "I'd have to classify Elvis's death as an accident. There's no one to blame - certainly not Elvis. He was a severely injured and ill man. There’s no specific negligence on anyone's part and definitely no cover-up or conspiracy of a criminal act. If Dr. Forrest Torrent is right, there simply wasn’t a proper understanding back then in determining what really killed the King of Rock & Roll."

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