Only have a second - but will post more later. DG started a great thread on bioidentical hormone replacement. I haven't had much time, but am still reading through it and will post on it.
Cortisol has to do with Adrenal Glands. Rebuilding the Adrenals can be accomplished through supplements, diet and
OH THE EASY TO ACCOMPLISH ......... STRESS REDUCTION 
You test the Cortisol levels through the saliva tests. I am on hormone replacement due to a Hyst. at a young age - and use bio identical compounds. I also take a forumla supplement for the Adrenals.
I think there is more info on that thread - but I will get back on here later and post more