Caffeine

Key Insight

● Caffeine - the best vice you can have! Many mental and health benefits, but there is a usage guideline you were not shown before...

● Do not consume in the first 90–120 minutes after waking - Adenosine is produced when our body generates energy, and the more adenosine there is in the blood, the sleepier we feel and the more fatigue we experience. Accumulated adenosine (together with the biological clock) signals our body to sleep. During sleep adenosine is cleared, but some time is needed to clear it completely after waking (about 90 minutes). Caffeine acts as an adenosine blocker (which is why it wakes us up); however even if adenosine is blocked, it’s still in the bloodstream, and if you drink caffeine right after waking adenosine will return later in a stronger form, causing an afternoon crash and fatigue.

● Do not consume caffeine 10 hours before sleep - Sleep is the absolute key precursor to effectiveness, and caffeine before sleep can significantly disrupt sleep. The half‑life of caffeine in the blood is 3–5 hours (depends on the person and conditions), which means that 10 hours leaves enough time for caffeine to break down sufficiently to not affect sleep. This can be quite individual, but a cup of coffee before bed certainly won’t help your sleep. Ideally drink 0.5–1 cup daily, and better earlier in the day in a slower form rather than all at once. If you sleep well and have a well‑adjusted clock you should not expose yourself to too many cheap dopamines; with enough physical activity and general psycho‑physical health you should not need more than 1 (2 at most) cups of coffee per day.

● A small percentage of people even small amounts of caffeine have a very negative effect on sleep. If you’ve followed all other tips in the sleep section and still can’t achieve 8 hours of good sleep, try completely eliminating caffeine. For the first ~5–7 days it will be very hard (withdrawal symptoms) but it’s quite possible that it will significantly improve sleep quality. I personally don’t have this problem (and I’m grateful for that), but if I decide to drink a second cup later in the day the likelihood of poor sleep increases significantly, and I even notice a slight correlation with worse mood the next day if I do. Alternatively you can try lower‑caffeine beverages such as tea or yerba mate (just “mate” in our language).