How caffeine REALLY affects the brain

Added: 2026-05-17

[00:00:00]to researchers at Wake Forest in North Carolina where I underwent two MRI brain scans. This first scan with no caffeine in my system. Then I down just one drink. Now my second MRI. This was my brain before caffeine. This was after.

[00:00:19]The difference was remarkable.

[00:00:21]>> It's like a 40% drop in the blood flow to your brain. So that's a lot. So before caffeine, with caffeine, the blood flow to my brain dropped about 40%. That's insane.

[00:00:34]>> Really?

[00:00:34]>> So you mean to tell me that caffeine reduces blood flow to the brain?

[00:00:38]Absolutely. And that's literally exactly how it stops migraines? Yes. Caffeine is a major component of medications to stop migraines like eedrain migraine. But if you're going to look at another MRI technique called functional MRI, caffeine actually boosts activity in the brain responsible for attention, concentration, focus, there are actually even studies to show that it reduces neurodeenerative changes. So the fact that it reduces blood flow might sound bad, but it's completely meaningless and taken out of context. And this video was really meant to just get views. Don't worry, your brain is not starving from blood flow. After a one cup of coffee, you'll be fine.