The evidence is convergent. Multiple independent sources reach the same conclusion, the underlying mechanism is well-characterized, and even the field's most cautious voices treat it as worth doing.
Caffeine works by blocking adenosine, a molecule that builds up the longer you’re awake and makes you feel tired. But right after waking, adenosine levels are at their lowest, meaning there’s not much for caffeine to block.
Every Sunday: the week’s new conflicts and verdict changes — and nothing else.
Native comments, Twitter mentions, and Reddit threads about this claim — surfaced together so the conversation isn't fragmented across platforms.
Bookmarking — the dossier-vs-overview split is the right call. Most of the time I want overview; sometimes I want receipts.
Would love a "what would change this verdict" RSS feed. Sign me up if it exists.
Dr. Michael Grandner (@michaelgrandner) explains how waiting approximately one hour after waking allows adenosine levels to naturally accumulate, creating optimal conditions for caffeine to bind more effectively and producing a robust and measurable enhancement in alertness and cognitive performance.
So the reason for delaying caffeine for the first two hours of the day even if it's painful to do for the first couple of days is that then you naturally start to wake up, more readily in the morning without caffeine because, the adenosine is suppressed and you don't have these competing.
I'm a big proponent of delaying caffeine intake for a few hours after waking for other reasons that my listeners have heard me talk about endlessly so I won't bother with that now but I think um allowing the suffice to say that allowing some of the natural waking up signals to occur and using light to kind of clear away and adenosine to further extend an activity is better than using a stimulant but until a few hours later
caffeine can make your brain more metabolically active which means that you're going to build up more adenosine during the day which means that sleepiness is going to arrive earlier
I think it is good advice for people to test and it's good advice for two reasons
if they are to drink caffeine right away then they're as you pointed out going to block those adenosine receptors and there's going to be a continued buildup of adenosine as opposed to a clearance of adenosine
One of the best ways to ensure a caffeine crash is to drink a bunch of caffeine, block all those adenosine receptors, and then by early or late afternoon when that caffeine starts to wear off and gets dislodged from the receptors, a lower level of adenosine is able to create a greater level of sleepiness.