Living · 6 pages · 12 min
Why caffeine late in the day lingers
Caffeine blocks the sleepy signal for hours while sleep pressure keeps rising underneath.
When the purchase is complete, return to the original window. It will refresh.
From the opening
Caffeine late in the day lingers because the liver clears it over hours rather than minutes, and people differ in the pace. While it remains, it blocks adenosine receptors, so the sleep signal is muffled even as adenosine keeps accumulating. The opening covers receptor block hides the pressure, liver clearance sets how long it lasts, and people clear the same dose differently.
The rest of the brief — the later sections and the reading notes — opens after Stripe confirms payment.
Inside
- Receptor block hides the pressure
- Liver clearance sets how long it lasts
- People clear the same dose differently
- Melatonin timing can shift as well
- Where the idea stops applying
- A distinction worth keeping
Sources
- Caffeine as an antagonist at adenosine receptors
- CYP1A2 and person-to-person differences in clearance