Quiz: The Cold, Hot Facts About Body Temperature

Spanish scientists say there’s truth to what they’re calling the “Pinocchio effect.” But it’s not just your nose; the area around your eyes may get warmer, too. Researchers at the University of Granada say we feel anxious when tell a lie, and that’s what causes the temperature change.

Your mom was looking out for you when she made you put on a hat to go out in the cold, but a warm coat and gloves were just as important. You’ll lose heat from any part of your body that’s not covered -- but no more than 10% of it escapes through your uncovered head. Keep warm by dressing right for cold weather from head to toe.

It’s not just the stuff of crime dramas. When someone dies, his body gives off heat until it’s the same temperature as the air around him. You can get a rough idea of how long someone has been dead if you put the palm of your hand under the person’s arms. If the body is warm, he died a few hours earlier. If it’s cold and clammy, it’s been at least 18 to 24 hours.

Running a temperature is no fun, but it’s how your body fights off the germs that are making you sick. When your temperature is just a few degrees above the normal 98.6, it means you’re healthy enough to battle the infection. For adults, it’s not usually something to worry about unless it's above 102 degrees. But call the pediatrician if your baby has a fever of 100.4 or higher and is younger than 6 months, or is younger than a year old and has one for more than 24 hours.

Lots of things can affect how hot or cold you feel, including the weather. But caffeine and stress -- along with dehydration, exercise, and certain problems with your thyroid gland -- can all affect your body’s thermostat, too.

Your body usually dissolves sweat to stay cool, but that can be hard when it’s hot and humid.  If your body can’t keep itself cool, your temperature goes up. A person with heatstroke may not be sweating. He may have trouble breathing and have red or flushed skin. It can cause shock, brain damage, and organ failure. Call 911 right away if you think someone has heatstroke.

Hypothermia means “low heat,” and it can be serious. It happens when you’re in the cold and heat escapes your body faster than it can be replaced. Your temperature can get too low from cold weather, high or cold wind, dampness, or cold water. Hypothermia is common in the spring and fall because it can happen with temperatures in the 50s if it’s rainy and windy. But it is most likely to happen in the winter when the weather is cold.

Your normal 98.6 F is just a starting point. Your temperature goes up 1 to 2 degrees from early morning until late afternoon and then goes down again. It’s at its lowest a couple of hours before you wake up. You probably feel most awake and alert when your temperature is going up and most sleepy when it’s on the way down.

After an ovary releases an egg, your temperature is a bit higher when you first wake up than during other times of the month. You’ll need a special thermometer -- called a basal thermometer -- and be sure to track your temp every day for a few months so you can see a pattern.

Always cold? It might have something to do with your age. With seniors, the normal body temperature usually drops below 98.6. That can make it harder for people to figure out when they have a fever. 

Don’t eat or drink anything for at least 5 minutes beforehand: Hot or cold food or drink can affect the reading. It’s a good idea to keep your mouth closed as well. Wash your hands with warm water and soap first; be sure to rinse the thermometer in cold water, clean it with rubbing alcohol, and rinse it off.

Glass thermometers can break, and mercury is poisonous. If you have a mercury thermometer, you should get rid of it. Call your local fire or health department to find out the safest way to do that.