44y male have low temp for periods 34.5 - 36c. fit, clean life, no stress, rhr 50 and bp 110/70. feel poor. no brain. blood done t3 (liothyronine) slightly low?

Was TSH checked?: Check the tsh. If your T3 (liothyronine) level was slightly low you may have hypothyroidism, but cannot be diagnosed with only a T3 (liothyronine) level. Your symptoms, however, can be signs of hypothyroidism. The low rhr and BP may be due to your physical good health. Agree that further evaluation is necessary. Pituitary disease can cause low temperatures. Where temp taken can influence result (ie. Ear, armpit, mouth).