The Pope had become nearly blind in one eye and had been falling out of bed 'several times' whilst on foreign trips, making him very tired for his papal duties, according to a report on the Vatican Insider.
Pope Benedict XVI, or Joseph Ratzinger as he will soon be known, had been told by his doctor to avoid air travel due to soaring blood pressure and had began using a walking stick even to get around his own home.
He had specifically advised to avoid travelling to Rio de Janeiro for World Youth Day later this year, reported AFP.
The leaked report comes just over a week since the Pope announced he would resign on February 28, citing health reasons.
At 85 year olds, he said he was "no longer suited" to the the challenges his role demanded. He was the first pope to resign for over 600 years.
The Vatican later confirmed that pontiff has a pacemaker and had to have surgery to replace the batteries three months ago. However they said this was not a factor in his resignation.
The next Pope is expected to be appointed before March 1. The top Catholic theologians in line for the Papacy come from diverse countries, backgrounds and many have courted controversyy over some more entrenched, traditional views of the church on issues like homosexuality and women.
Ghana's Cardinal Peter Turkson, the man who could be the first black Pope has said sex abuse could not happen in Africa, on the same scale as Europe, because of tough anti-homosexuality laws.
He caused outrage among former victims of sexual abuse by priests for linking progressive attitudes to homosexuality and child abuse.
Survivors of abuse by priests say they "fear for the safety of kids in Turkson's diocese if he denies there are predatory priests there".
Cardinal Turkson is currently the second favourite to be the next pontiff, and had been championed by progressives who have urged the Vatican to elect the first African pope.
Canadian Cardinal Marc Ouellet is one of two top runners, and showed his progressive side in 2007, when he published "An Open Letter To Quebec's Catholics" where he apologised for previous "discrimination against women and homosexuals."
He noted also that those "narrow attitudes of some Catholics, before 1960, have promoted Anti-Semitism, racism," and "indifference to the First Nations."
Cardinal Angelo Scola of Milan is also among the favourites to succeed Benedict XVI.