Question: how fast does your blood travel around your body?

Kate Elliott answered on 16 Nov 2016:

It depends where it is, in arteries it can be about 1.8 km/h but in veins it is more like 0.5km/h. There were some dodgy experiments in the past to try and work out how fast blood flow was by injecting people with radioactive stuff in one arm then timing how long it took before they could detect the radiation in the other arm! Luckily we now know more about blood flow and radioactivity and we don’t do that anymore!