Roberto Canessa, a survivor of the Uruguayan rugby team that crashed in the Andes in 1972 and resorted to cannibalism to survive, recounts the horrors in a new book.

Survivors of the Uruguayan rugby team that crashed in the Andes in 1972

In 1972 Uruguayan rugby team members Roberto Canessa, Nando Parrado, and 43 other passengers of Flight 571 crashed in the Andes mountains. 18 died immediately or in the following days as a result of their injuries. The 27 remaining survivors battled bitter cold temperatures, an avalanche, and other hardships while they waited 72 days for a rescue that never came.

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With very few supplies, surrounded by nothing but the plastic and aluminum of the wreckage and the mountain’s rock and ice, the survivors soon found themselves starving. They tried eating strips of the leather seats from the plane, but one thing soon became clear: They would need to eat the flesh of their dead friends in order to survive.

In his new book I Had to Survive, Canessa, who was then a second-year medical student, describes the bleak moment:

“I will never forget that first incision nine days after the crash. Four of us … with a razor-blade or shard of glass in his hand, carefully cutting the clothes off a body whose face we could not bear to look at.”

There were only 16 survivors left by the time Canessa and Parrado climbed out of the mountains and got help. Helicopters transported those remaining off the mountain. It was only a matter of days before newspapers began reporting that they had resorted to cannibalism, an act that seems to haunt them to this day.

Andes plane crash survivor Roberto Canessa

Canessa’s new book, available March 1, centers around how this experience inspired him to become a pediatric cardiologist, believing that every time he has the chance to save a baby’s heart, he is giving back what was given to him when he was rescued.

Read it: I Had to Survive: How a Plane Crash in the Andes Inspired My Calling to Save Lives