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An empty tube, squeezing anyway

Why Does Your Stomach Rumble?

Your stomach does not stop working when it is empty — it sweeps itself out, and an empty tube is loud.

Squeezing continueswhen emptyNothing but air andjuice insideAn empty tube is a goodloudspeakerThe rumble is acleaning sweep
The noise means it is tidying, not starving.
  1. Step 1 of 5

    Your gut never stops squeezing.

    A ring squeezes Travels downthe tube And startsagain

    Rings of muscle travel down the tube whether there is food in it or not. With a meal inside, that is quiet. Empty, it is not.

  2. Step 2 of 5

    Empty means air, juice, and lots of room.

    After a meal Full, packed, quietEmpty Gas and juice, sloshingloudly

    Sound needs space to resonate in. Food damps everything; an empty stomach is a chamber of gas and liquid being sloshed about, and it carries.

  3. Step 3 of 5

    Every couple of hours it does a proper sweep.

    1 About 90minutes with nofood2 A strong wavesets off3 Sweeping thewhole tubeclear

    When nothing has arrived for a while, a strong wave runs from the stomach right through the small intestine, clearing out leftovers and bacteria.

  4. Step 4 of 5

    Hunger itself is a chemical, not an empty feeling.

    Around your usualmealtime The hunger hormonepeaks

    A hormone builds up when your stomach has been empty, and it peaks near the times you usually eat. That is why hunger arrives on schedule, not on volume.

  5. Step 5 of 5

    Which is why hunger comes in waves.

    Just after eatingthe signal islowTwo hours laterclimbingMeal missed, an hour onit has fallenagain

    Miss a meal and the feeling builds, then fades, then returns. The level rises and falls; it does not simply climb until you eat.

    Rumbles are louder when you are hungry but they happen after meals too — you just cannot hear them through the food.

The short version

A rumble is your empty gut sweeping itself out with nothing inside to muffle the noise, and hunger is a hormone that peaks on a schedule.

Try it yourself

Press an ear to a friend's stomach an hour after they last ate. The gurgling is there whether or not it is loud enough to hear across a room.

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