Peter Attia· MD
what makes our blood red is actually the iron that's contained within it so what you can actually do is you can take all the blood that's let's say flowing to a particular organ like the head so anything that's flowing up and you say okay I'm gonna actually excite anything going up north to the brain and so therefore that's arteries and so then you'll actually get to see all the exquisite arteries in your brain just by exciting that blood