2 min
Why does my stomach rumble when I'm hungry?
Answer
You are sitting in a quiet classroom when your stomach suddenly goes "grrrr" and the whole class turns around. You feel embarrassed and hold your belly. But is that sound really coming from your stomach? Guess first: is it the stomach, or somewhere else?
1. The sound comes from the gut
Inside your intestines there is gas, food scraps, and rings of muscle that squeeze. These muscles push things forward in waves, like squeezing milk out of a bottle. When gas is pushed past liquid in a narrow tube, it makes that gurgling sound.
2. An empty stomach makes it louder
When your stomach is empty, the space inside is hollow, and the sound of moving gas gets amplified by that empty room. It is like talking in an empty classroom, where the echo is much bigger. So the hungrier you are, the louder it gets.
3. It is cleaning on a schedule
About two hours after your stomach empties, the "migrating motor complex" starts up and sweeps leftovers forward, roughly once an hour. It happens right when you feel hungry — it is the real source of that hungry growling.
Guess with me
- Guess: If you drink only soda and do not eat, will your stomach still gurgle? Where does that gas come from?
- Try it: Tomorrow morning, stay quiet for one minute while you are hungry and count the growls. Then eat something and count again. Tell Michael both numbers.
- Ask me: Doctors listen to bowel sounds to check if someone is sick. But if they hear no sound at all, does that mean the person must be sick?
Send your answer to Michael
Thought about the three questions? Write to me — I will answer a few in the next post.
Email MichaelWrite to Michael
Write down your answer and press send — it lands in my inbox. I will answer a few in the next post.
I'm Michael
I always thought my stomach was grumbling because I had not eaten well. Turns out my gut was just working a shift on a schedule. I had blamed it for a long time.
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