For poor metabolizers like me, caffeine has about a 12 hour half life and I can’t even sleep if I have a small dose in the morning. I know this is true because I’ve accidentally taken caffeine in various forms and it’s always 3am and I’m banging my head trying to figure out why I can’t sleep until I realize I had a chai tea or something without thinking.

In fact caffeine is a huge detriment to my ability to be productive, and the last time I quit coffee it took a full month and a half for the grogginess and lethargy to go away. Never again!