10 Deadly Things People Used To Think Were Harmless

By Peter Austin / February 5, 2016

6. Bloodletting

As far back as 1000BC, assorted quacks have held the risible belief that too much blood can be bad for you. A medieval doctor might have treated almost any medical complaint by fetching a knife, cutting a limb or two and letting out some of that bad, bad blood.

Naturally, there€™s actually not a great deal to be said for needlessly opening up one of your patients and bleeding them like a radiator. Invariably, patients would feel nauseous and lightheaded or, at worst, die of infection or blood loss. Obviously.