Just last week I wrote a post reviewing the evidence on caffeine cycling and caffeine habituation. My conclusion was that the evidence was thin and it’s hard to say anything with confidence.[1]
My weakly held beliefs are:
Taking caffeine daily is better than not taking it at all, but worse than cycling.
Taking caffeine once every 3 days is a reasonable default. A large % of people can take it more often than that, and a large % will need to take it less.
I take caffeine 3 days a week and I am currently running a self-experiment (described in my linked post). I’m currently in the experimental phase, I already did a 9-day withdrawal period and my test results over that period (weakly) suggest that I wasn’t habituated previously because my performance didn’t improve during the withdrawal period (it actually got worse, p=0.4 on a regression test).
[1] Gavin Leech’s post that you linked cited a paper on brain receptors in mice which I was unaware of, I will edit my post to include it. Based on reading the abstract, it looks like that study suggests a weaker habituation effect than the studies I looked at (receptor density in mice increased by 20–25% which naively suggests a 20–25% reduction in the benefit of caffeine whereas other studies suggest a 30–100% reduction, but I’m guessing you can’t just directly extrapolate from receptor counts to efficacy like that). Gavin also cited Rogers et al. (2013) which I previously skipped over because I thought it wasn’t relevant, but on second thought, it does look relevant and I will give it a closer look.
Just last week I wrote a post reviewing the evidence on caffeine cycling and caffeine habituation. My conclusion was that the evidence was thin and it’s hard to say anything with confidence.[1]
My weakly held beliefs are:
Taking caffeine daily is better than not taking it at all, but worse than cycling.
Taking caffeine once every 3 days is a reasonable default. A large % of people can take it more often than that, and a large % will need to take it less.
I take caffeine 3 days a week and I am currently running a self-experiment (described in my linked post). I’m currently in the experimental phase, I already did a 9-day withdrawal period and my test results over that period (weakly) suggest that I wasn’t habituated previously because my performance didn’t improve during the withdrawal period (it actually got worse, p=0.4 on a regression test).
[1] Gavin Leech’s post that you linked cited a paper on brain receptors in mice which I was unaware of, I will edit my post to include it. Based on reading the abstract, it looks like that study suggests a weaker habituation effect than the studies I looked at (receptor density in mice increased by 20–25% which naively suggests a 20–25% reduction in the benefit of caffeine whereas other studies suggest a 30–100% reduction, but I’m guessing you can’t just directly extrapolate from receptor counts to efficacy like that). Gavin also cited Rogers et al. (2013) which I previously skipped over because I thought it wasn’t relevant, but on second thought, it does look relevant and I will give it a closer look.
Update: I finished my self-experiment, results are here: https://mdickens.me/2024/04/11/caffeine_self_experiment/
Thank you, that’s really cool! I’ll look at your post when I have time.