Basal body temperature is the temperature of the body when one is at rest. It is the lowest temperature of a human when at rest or measured immediately after waking up from sleep (before taking up any kind of physical activity). Usually, the normal basal body temperature of a person would be around 97.8 degrees to 98.2 degrees Fahrenheit. However, this normal varies from person to person, men to women, and hormonal changes. Women during ovulation periods experience higher basal body temperatures. Their temperatures decrease before ovulation and rise afterwards. This patterns is known as biphasic pattern. Diabetes has a profound effect on the basal body temperature of a person as insulin acts as the body’s internal thermostat. People with type 1 diabetes tend to have a basal body temperature of less than 97 degrees Fahrenheit. At times, high insulin levels might even cause chills in people with type 2 diabetes. Basal body temperature is measured by a basal body thermometer (See: Basal Thermometer).