I have heard that also (about cortisol), but the adrenals secrete adrenaline/epinephrine; it may be your adrenaline/epinephrine hormones (from the adrenals)which driving your heart through your sympathetic nervous system. You don't have to drink coffee, if you did, that could make aggravate matters. I am only speculating, because I cannot see you or examine you. The book is called The five elements of self healing by Jason Elias, I think they have redistributed the book under a different name. It is called Chinese Medicine for Maximum Immunity by Jason Elias,available through the Amazon website for about 20. Sigg