Why do you get butterflies in your stomach?

Monday, May 10, 2010

Imagine the following scenarios:

-- It's Monday morning and you're worried because you have a math test.

-- It's Saturday afternoon and you're getting ready to give a piano recital for a group of adults.

-- A girl or boy you like is nearby and you want to say something, but you don't know what to say.

In each situation, you have an uncomfortable or fluttery feeling in your stomach. You might also worry that you're going to throw up. If you pay attention to the rest of your body, you may notice that your heart is beating faster, your mouth is dry and your hands are damp and a little shaky.

This situation has happened to every human at one time or another. The experience is referred to as having "butterflies in your stomach." What's really going on, however, is that you are experiencing a reaction to stress.

When people are stressed, they experience something called the "fight-or-flight" response. Let's pretend you came upon a lion on the African savanna. In a split second you know you are in a dangerous situation. Fortunately, the human body is prepared to deal with this. Signals travel from the thinking part of your brain to the hypothalamus and pituitary gland, which are in your brain and responsible for controlling many bodily functions. The pituitary gland instantly signals the adrenal glands, which sit on top of each kidney. The adrenal glands release adrenaline and other chemicals into your blood stream. Adrenaline causes rapid heart rate, increased blood pressure and improved circulation in your muscles. All of those effects are designed to help you fight the lion or run away. (I recommend the latter.)

At the same time that blood is flowing to your lungs and muscles, less of it is reaching other organs including your stomach. This and other hormonal changes may cause nausea. Even though man is unlikely to encounter a lion, a milder version of the same process kicks in in less stressful situations. That's "butterflies" in your stomach.

So the next time you are nervous before taking a test, remember that it is the fight-or-flight response that's making you feel this way. In this case, however, I recommend that you take the test instead of running away.

-- Howard Bennett

Howard Bennett, a pediatrician and author of health-related books for kids, writes about gross things for KidsPost.

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