In 1972, Roberto Canessa was one of 45 people aboard a plane that crashed high in the Andes mountains.

Twelve were killed in the crash, six died in the next few days, and 11 more perished due to the lack of food and harsh conditions they faced.

Those who were left ate the bodies of the dead in order to have any chance of living long enough to be rescued.

Forty years on Dr Canessa is a successful cardiologist specialising in treating unborn babies and children with heart problems.

He spoke to Victoria Derbyshire presenter Joanna Gosling about the book he has written, I Had to Survive: How a Plane Crash in the Andes Inspired My Calling to Save Lives.

Watch the full interview with Dr Canessa here.