Stat1951 you make a good point that anything inclined to elevate cortisol levels is undesirable, BUT
cordyceps also raises testosterone, which is anabolic and hence will help offset the marginal gain in cortisol levels
Also, cortisol is only bad when levels are high enough to cause catabolism - low cortisol levels are very bad too (completely wipes you out)
The solution is simple - stack
Cordyceps with other supplements that LOWER cortisol levels (e.g.
Rhodiola, PS, Gerovital-H3, 7-Keto OH (e.g.
Lean Xtreme) etc.) and you can reap the benefits of
Cordyceps (e.g. increased testosterone) without worrying about cortisol levels!