I suspect you already have high cortisone and that is one of the reasons that you have high level of lactate and low weight. Since cortisone rises when your body looking for sugar you should increase your intake of sugar in a form of fruits and honey if not allergic to it. You should work with professional nutritionist or spend some time on reading Ray Peat articles, but in this short reply I can tell you that low body temperature points out on inefficient oxidative metabolism - the reason could be low thyroid, high adrenalin from some stress or low sugar consumption, low protein consumption, missing vitamins - A(from liver and not betta carotene)/B's/E/D3/K2, sedentary life stile, depression, unnatural or toxic food....T3 make me cold someone suggested I try cortisone accitate with it.