Another anecdote, this is mine: I made a change in my lifestyle and I can work faster and for about three times the hours I was working before that. My lifest

Another anecdote, this is mine: I made a change in my lifestyle and I can work faster and for about three times the hours I was working before that. My lifestyle change is not related to caffeine, I stopped eating lots of carbs and now I follow a keto diet. YMMV, etc.