A body temperature of 35.7 degrees Celsius can vary individually and can be normal if there are no uncomfortable symptoms. It can also be caused by low ambient temperatures or inaccurate measurements, and may be caused by hypothyroidism. Measuring the axillary temperature between 36~37℃ is normal, if the surrounding environment is low, the body exposed to the environment will have a certain degree of body temperature drop, which may lead to a body temperature of 35.7℃. When an electronic thermometer is used to measure the body temperature through the wrist, the difference in skin temperature on the surface of the body will also affect the measurement result, and such a low situation may also occur. Patients with hypothyroidism, due to metabolic abnormalities, body temperature will be significantly lower, the body will be more sensitive to cold, but also make the limbs feel weak, may affect the mental state, prone to fatigue and drowsiness, and some patients will be swollen. Body temperature of 37.5 ℃, such as no discomfort, do not have to worry too much; if repeated measurements are still lower than the normal body temperature, or physical discomfort, need to go to the hospital in time for examination, to avoid delaying the condition.