If I just had high caffeine tolerance I’d guess it’s either because of fast caffeine metabolism or my ADHD. Sometimes a regular cup of coffee is more than enough to wake me up and improve my ability to concentrate and sometimes not even a 4x Espresso is enough, with no discernible reason why. I have tried drinking coffee on an empty / full stomach, which doesn’t seem to make a difference. Any idea why this might happen?
Edit: Things that might matter:
- I am getting enough sleep
- I have normal body weight (BMI slightly below 24)
- I would consider my diet balanced, although I do like eating fastfood sometimes
I used to teach at a college for kids with disabilities, a lot of ADHD kids self medicate with caffeine and rather than have the buzz that happens to others it calms their minds and improves their focus.
No scientific data but I assume it reacts differently with the ADHD brain in a similar way that amphetamines are proven to.