Didn't know that. All I know, is after dropping below 5%, I felt miserable, and almost ached. The aching was of course, partly due to the crashing of my estrogen with Arimidex, winstrol, masteron, Proviron, and at the end, femara. (Yeah, I know, may be partly why I'm at the docs ofc now...)
^ These being the ones known to affect estrogen/progestins. Was also using test, tren, var, etc., Bruised easily at that body fat, ached, got the sniffles/colds very easily, shivered cold at times, and was just generally uncomfortable. Loved the outer space look, but very dangerous. Going below 6% I never recommend. And damn, the difference between 6% and 4% is night and day! The changes that occur, I can't really type out. It's just evil getting there, lol. If the CNS holds that much, imagine how "healthy" I was in the high 3's. Crash cart? Lol