Hey, Brain Stuff, I'm Lauren Vogelbaum, and this is another classic episode.

Today, we're returning to the story of a man whose blood donations saved over 2 million

babies over the course of a few decades, and as of this recording, he's doing just fine,

by the way.

Hey, Brain Stuff, Lauren Vogelbaum here, when currently 81-year-old John Harrison was

just 14 years old, he received a blood transfusion following a major chest surgery.

He had a lung removed, and 13 units or pints of other people's blood that's nearly two gallons

made their life-saving way into his veins.

That transfusion inspired Harrison's later generosity.

He promised to begin donating once he turned 18 and did so weekly until May 11, 2018, when

according to the Australian Red Cross, he gave his final donation.

He's fine, that's just the maximum age in Australia for giving blood.

Harrison's prolific donation is notable enough that in 2003, Guinness World Records recognized

his achievement for the most blood donated by a single person.

His record was broken in 2015, but we'd say it's still nothing to sneeze at.

And Harrison's blood is notable not only for quantity, but also for quality.

He's credited with saving the lives of more than 2 million Australian babies.

Harrison, known in Australia as the man with the golden arm, produces a rare and powerful

antibody in his blood called RHD immunoglobin, or anti-D.

It protects unborn babies from the potentially deadly condition, RH incompatibility.

When a pregnant woman with an RH negative blood type carries a baby with RH positive blood,

the woman's body mistakenly treats the baby's red blood cells like an outside threat.

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