If you take caffeine regularly, I also recommend experimenting with tolerance build-up, which the pill form makes easy. You want to figure out the minimal number of days N such that if you don’t take caffeine every N days, you don’t develop tolerance. For me, N turned out to be equal to 2: if I take 100 mg of caffeine every second day, it always seems to have its full effect (or tolerance develops very slowly; and you can “reset” any such slow creep-up by quitting caffeine for e. g. 1 week every 3 months).
You can test that by taking 200 mg at once[1] after 1-2 weeks of following a given intake schedule. If you end up having a strong reaction (jitteriness, etc., it’s pretty obvious, at least in my experience), you haven’t developed tolerance. If the reaction is only about as strong as taking 100 mg on a toleranceless stomach[2], then you have.
(Obviously the real effects are probably not so neatly linear, and it might work for you differently. But I think the overarching idea of testing caffeine tolerance build-up by monitoring whether the rather obvious “too much caffeine” point moved up or not, is an approach with a much better signal/noise ratio than doing so via e. g. confounded cognitive tests.)
Once you’ve established that, you can try more complicated schemes. E. g., taking 100 mg on even days and 200 mg on odd days. Some caffeine effects are plausibly not destroyed by tolerance, so this schedule lets you reap those every day, and have full caffeine effects every second day. (Again, you can test for nonlinear tolerance build-up effects by following this schedule for 1-2 weeks, then taking a larger dose of 300-400 mg[3], and seeing where its effect lies on the “100 mg on a toleranceless stomach” to “way too much caffeine” spectrum.)
You can establish that baseline by stopping caffeine intake for 3 weeks, then taking a single 100 mg dose. You probably want to do that anyway for the N-day experimentation.
I second that.
If you take caffeine regularly, I also recommend experimenting with tolerance build-up, which the pill form makes easy. You want to figure out the minimal number of days N such that if you don’t take caffeine every N days, you don’t develop tolerance. For me, N turned out to be equal to 2: if I take 100 mg of caffeine every second day, it always seems to have its full effect (or tolerance develops very slowly; and you can “reset” any such slow creep-up by quitting caffeine for e. g. 1 week every 3 months).
You can test that by taking 200 mg at once[1] after 1-2 weeks of following a given intake schedule. If you end up having a strong reaction (jitteriness, etc., it’s pretty obvious, at least in my experience), you haven’t developed tolerance. If the reaction is only about as strong as taking 100 mg on a toleranceless stomach[2], then you have.
(Obviously the real effects are probably not so neatly linear, and it might work for you differently. But I think the overarching idea of testing caffeine tolerance build-up by monitoring whether the rather obvious “too much caffeine” point moved up or not, is an approach with a much better signal/noise ratio than doing so via e. g. confounded cognitive tests.)
Once you’ve established that, you can try more complicated schemes. E. g., taking 100 mg on even days and 200 mg on odd days. Some caffeine effects are plausibly not destroyed by tolerance, so this schedule lets you reap those every day, and have full caffeine effects every second day. (Again, you can test for nonlinear tolerance build-up effects by following this schedule for 1-2 weeks, then taking a larger dose of 300-400 mg[3], and seeing where its effect lies on the “100 mg on a toleranceless stomach” to “way too much caffeine” spectrum.)
Assuming it’s safe for you, obviously.
You can establish that baseline by stopping caffeine intake for 3 weeks, then taking a single 100 mg dose. You probably want to do that anyway for the N-day experimentation.
Note that this is even more obviously dangerous if you have any health problems/caffeine contraindications, so this might not work for you.