As Pope Francis begins a trip to the Holy Land on Saturday with a rigorous schedule that could be challenging even for the healthiest person, Vatican insiders are raising questions about the pontiff's health.
Some in the Holy See are beginning to openly discuss concerns about Francis' condition and asking if the Holy Father is overtaxing himself.
Less than two years into his papacy, the 77-year-old Pope has been on a remarkable whirlwind of activity that a man half his age might find difficult to keep up with.
But close observers are noting that the Pope's physical body may be failing to keep up with his youthful energy and vigor, especially considering he only has one fully functioning lung.
Francis: Who Is Pope Francis? Book Reveals the Man
As a young boy in Argentina, before the advent of advanced antibiotics, the Pope suffered an infection which led surgeons to remove most of one lung.
He has appeared to cope with that well through the years, but recently the Pope has canceled a number of papal appointments, citing health reasons.
Although planned months ago, the Pope last week put off a visit slated for May 18 to the Marian shrine of Divino Amore in the suburbs of Rome. The reason given was to "lighten the commitments" of the Pope ahead of his Holy Land visit, but further cancellations followed that weekend owing to a cold.
These are not the only times appointments have been delayed or canceled in recent months.
On Feb. 28, Francis called off a visit to Rome's Major Seminary due to a "light fever."
And before that, in early December, he felt compelled to cancel, at the last minute, a meeting at the Vatican with Cardinal Angelo Scola, archbishop of Milan, who came with a delegation from Expo 2015. The Vatican said the Holy Father had "expressed fatigue" after a general audience in St. Peter's Square in which he had greeted the faithful for nearly three hours.
Indian Cardinal Telesphore Placidus Toppo, archbishop of Ranchi, told the Italian daily Libero that he concelebrated Mass with the Pope for a few days last summer and found him "very tired and fatigued."
He added: "I honestly do not know how long he might be able to sustain this pace that he's certainly not accustomed to."
Last September, the Argentine magazine Noticias reported that the Pope's personal physician in Argentina had said he was "concerned" about his patient's health.
"I have the impression that something is wrong," explained Liu Ming, a Chinese Taoist doctor who claims to have helped cure the future Pope from heart and liver problems through acupuncture and other Oriental treatments.
But Vatican spokesman Father Federico Lombardi is playing down any fears. The visit to Divino Amore would be "very challenging" given Francis' usual wish to meet so many people and groups. "I think he thought: 'Well, we can do all that another time,' and that shouldn't be considered a cause for concern," he said.
Some close to the Pope have said they notice he has difficulty breathing, and during the 14 months of his papacy has gained a significant amount of weight, perhaps as much as 20 pounds.
"It's a very serious condition," Dr. Peter Hibberd told Newsmax in discussing the Pope's single lung.
"If you are 20 years old and have one lung, you wouldn't notice it because all humans have a large reserve capacity in their lungs," said Hibberd, a 30-year hospital and emergency medicine specialist who writes for Newsmaxhealth.com.
Hibberd noted that as they age, people "lose lung function," which in turn makes the extra or "reserve" capacity of the lung more critical in keeping the blood well oxygenated while allowing the body to exchange gases.
"His repeated fatigue reports and weight gain suggest he may be slipping into a form of chronic heart failure common among victims of significant lung disorders such as COPD," Hibberd suggested.
"His immunity will be challenged when under stress, and more frequent pauses to recover from otherwise small insults — such as colds, sore throats, and minor injuries — can be expected to increase in the future unless he paces himself," Hibberd said. He noted that patients with chronic lung conditions require an inhaler and nighttime oxygen to breath comfortably.
The Pope's weekend trip to the Middle East will be grueling. Francis will give 15 discourses in Amman, Jerusalem, and Bethlehem during the 48-hour trip, from Saturday to Monday.
His visit follows the intensity of the last few weeks that have included leading the church's Easter celebrations and presiding over the canonization of Popes John XXIII and John Paul II.
The Pope's visit to the Holy Land is notable for being unusually short, especially given the obvious significance of the destination.
Lombardi said the Pope had received many requests to visit other areas such as Galilee, "but one cannot do everything."
In any case, he said, it has to be seen in the context of Pope Paul VI's historic trip in 1964. This visit commemorates the 50th anniversary of that visit, when Paul met the Ecumenical Patriarch of Constantinople, Athenagoras, in Jerusalem.
"Even that trip lasted three days," Lombardi said.
On his trip, Pope Francis plans to meet with the Ecumenical Patriarch Bartholomew I, also in Jerusalem.
Francis: Who Is Pope Francis? Book Reveals the Man
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