hypothyroidism: low thyroid function, often associated with hormonal imbalance (particularly estrogen dominance) and linked with cold body temperature (feeling cold all the time), weight gain, inability to lose weight, thinning hair, low libido, and depression. (yourhormonebalance.com)
A power outage of one day could be enough to cause hypothermia (excessively cold body temperature) or hyperthermia (excessively hot body temperature) for some herptiles. (morenapethospital.com)
However, radiologist Anna Bagenholm currently holds the record for surviving the coldest body temperature. (businessinsider.com)