In general, normal blood temperature is about the same as normal body temperature, or about 98.6℉ (37℃).
Blood outside of the body will remain the same temperature for only a few minutes. After a few hours, blood cells will die and the blood will reach room temperature.
As your body temperature changes, so does the temperature of your blood. In this article, we’ll explore how the body regulates its temperature and how blood plays a role in this process.
How does your body regulate temperature?
Your body’s temperature may change throughout the day based on what you’re doing — like exercising, sleeping, or eating.
If your body temperature gets too high or too low, a part of your brain called the hypothalamus uses a process known as thermoregulation to get your temperature back to normal.
Different mechanisms are used during thermoregulation, including vasodilation and vasoconstriction, sweating, and hormonal thermogenesis.
High body temperatures
Fevers
If your body temperature reaches 100.4℉ (38℃) or higher, it’s considered a fever. This can happen as a reaction to:
- Medications
- Infections
- Heart attacks or strokes
- Heat strokes
- Burns
- Inflammation
- Medical conditions including arthritis, hyperthyroidism, leukemia, and lung cancer
If you have a fever, your body will try to reduce your temperature through sweating or vasodilation. During vasodilation, your blood vessels grow larger to increase the blood flow through your body, which ultimately cools you down.
Mild fevers are usually treatable at home with fever reducers like ibuprofen or acetaminophen. In adults, high fevers above about 103°F (39.4°C) warrant a trip to the doctor.
Heat stroke
You may experience heat stroke if your body’s temperature is too high and you can’t regulate it. It usually results in rapid heart rate and hot skin. You may also lose consciousness.
Causes of heat stroke include:
- Drinking alcohol
- Dehydration
- Wearing heavy clothing
Heat stroke can be very dangerous. If you think you might be experiencing heat stroke, seek immediate medical treatment.