I wouldn't be surprised if Yerba mate (and maybe even coffee) had some alkaloids that modulate the effect of caffeine on the body. I recently discovered that co

I wouldn't be surprised if Yerba mate (and maybe even coffee) had some alkaloids that modulate the effect of caffeine on the body. I recently discovered that coffee contains (small amounts of) Harman and norharman, which are MAOIs and would definitely affect the effect caffeine has. (these MAOIs are also in tobacco! They enhance the addictive potential of nicotine)