Caffeine & Stimulants
Caffeine is the most-used psychoactive substance on earth and also one of the most mythologised — dehydration claims, tolerance claims, "it stunts your growth" claims that never had evidence behind them. This is the actual pharmacology and the actual trial data on stimulants people put in their bodies daily.
Nutrition Science for Creatives: What Actually Helps You Focus During Deep Work
Freelancers and knowledge workers get worse nutrition advice than athletes do. Here's what the cognition research actually supports for a working day, not a training block.
Meta-analysis
Best Foods and Drinks for Focus
Most 'brain food' content is aesthetic. This is the actual evidence on caffeine, glucose, and attention.
Meta-analysis
Does Caffeine Affect Sleep? The Half-Life Problem
Caffeine's half-life is longer than most people plan around — here's the trial that measured a 6pm coffee's effect on sleep at midnight.
Single RCT