Caffeine and Cognitive Performance: What It Really Does
Caffeine reliably sharpens alertness and attention, not memory or reasoning. What the trials show on dose, sleep timing, tolerance and safety.

Caffeine reliably sharpens alertness and attention, not memory or reasoning. What the trials show on dose, sleep timing, tolerance and safety.

L-theanine with caffeine gives a small, short-lived lift in attention. Here is what the trials show, who paid for them, and how to dose and test it.

Deep work is lost to switching, not lack of willpower. What the research says about interruptions, breaks and block length, and how to protect your focus.

Evidence for ingredients is not evidence for a stack. An honest look at what nootropic combinations are actually tested, why most aren’t, the real safety data — and how to build a stack that teaches you something.