Credit: Goldex(Flickr)

A grandad has saved the lives of more than two million babies by donating his blood.

James Harrison, 74, has given blood nearly a thousand times since doctors found he carries a rare antibody. In his blood plasma is the cure for Rhesus disease - which can cause severe anemia, resulting in brain damage or even death.

To date the Aussie has helped to ensure 2.2 million healthy babies. The grateful parents include his daughter, Tracey, whose son is safe and well thanks to his grandad.

James, of New South Wales, is so important his life was insured for a million Australian dollars.

Nicknamed the man with the golden arm, he became a donor after major chest surgery at 14 when he needed 13 litres of blood. Doctors found he carried the antibody. He had tests that led to the vaccine Anti-D.

James said: I've never thought about stopping. They insured me for a million dollars so I knew my wife Barbara would be taken care of. I had to sign every form going but I wasn't scared. I was glad to help.