Body temperature is one of the important signs of human health and it can indicate the presence of a disease, along with other vital characteristics like the pulse, respiration and blood pressure. All these signs are used to evaluate the overall health of a person and if one of them is not within the desired parameters, doctors will suspect a disease and perform additional tests.
Because the human body is exposed to different temperatures from the outside, which can range from cold to hot, it needs to adapt and keep the body temperature within a safe, healthy range. It does so by a function called thermoregulation.
When the temperature is high, the body warms up. Because it has to maintain certain, more or less fixed temperature range, it adapts by dilating the blood vessels and carrying the heat to the skin surface. This results is sweating which cools the body as the sweat evaporates. Similarly, when exposed to low temperatures, the body needs to warm up and the blood vessels shrink so the skin can keep the body heat. Shivering, which happens when a person is cold, is contraction of the muscles which contributes to raising the body temperature.
Average and normal human body temperature
If the body temperature measures above or below the average range, it may be a sign of an underlying disease. It commonly happens during infections, like cold or flu, but it can also be sign of more serious and hidden infection. A rise in body temperature can also be caused by certain medications, like antibiotics, narcotics, antihistamines, by a trauma or injury, or conditions like cancer, arthritis, and others. This is why any rise in body temperature that persists needs to be reported to a physician.
Low body temperatures can occur after exposure to cold, but also as a result of sepsis, alcohol abuse, substance abuse and some metabolic disorders.
For adults, the average body temperature is considered to be that of 98.6°F or 37°C when the body is resting and when measured under the armpit. If measured orally, the normal range is 98.2±1.3°F or 36.8±0.7°C.
Children normally have 96.8 to 98.24°F body temperature and for the babies the range is 96.8°F to 98.6°F or 36°C to 37°C. Anything below 96.8 degrees Fahrenheit is a sign that the baby is cold and needs warming up. A temperature between 98.6°F and 99.5°F can indicate a low grade fever or that the baby is simply overdressed. A fever is usually indicated by a temperature of 100.4 degrees Fahrenheit.
Women who are trying to become pregnant often measure their body temperature to determine the exact time of ovulation, because during ovulation, due to a rise in hormone levels, the temperature slightly rises as well. Also, when a woman conceives, the progesterone levels slightly elevate the temperature and it usually stays that way all through the pregnancy.