How long digestion takes can vary by individual. If you feel you have to poop after every meal, you might have an overactive gastrocolic reflex, which is a natural reflex to eating.

Do you ever have to rush to the bathroom after eating? Sometimes it can feel like food “goes right through you.” But does it really?

In short, no.

When you feel the need to relieve yourself right after eating, it’s not your most recent bite that sends you rushing to the toilet.

Digestion time varies from person to person. Your age, sex, and any health conditions you may have also affect digestion.

The entire digestive system can be up to 30 feet long in adults — much too long for food to pass right through you. What’s most likely happening to you is something called the gastrocolic reflex.

Keep reading to learn more about the gastrocolic reflex, why it may cause you to poop after eating, and how to manage it.

How long does it take for food to pass through your digestive system?

Generally, it takes anywhere from 10–73 hours for food to pass through your body as stool, according to a key 2014 study. A more recent study confirms that digestion times vary among people and notes that the median time is about 28.7 hours.

Since multiple factors are involved in the digestive process, it’s difficult to give a good estimate of digestion time. Research suggests that age, gender, and body mass index may play a role.

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The gastrocolic reflex is a natural reaction your body may have to eating food.

When food hits your stomach, your body releases certain hormones. These hormones tell your colon to contract to move food through your colon and out of your body. This makes room for more food.

The effects of this reflex can be mild, moderate, or severe. They can also vary from person to person.

Some people experience the gastrocolic reflex more frequently and more intensely than others.

Research suggests that certain digestive disorders, such as irritable bowel syndrome (IBS), speed up the movement of food through the colon after eating.

Certain foods and digestive disorders may trigger particularly strong or long lasting effects of gastrocolic reflex. These include:

When these disorders worsen your gastrocolic reflex, you’ll usually experience other symptoms, like:

Sometimes you might feel an urgent need to poop that isn’t related to your gastrocolic reflex. This could be the case when you have diarrhea.

Common causes of diarrhea include:

Why do I poop diarrhea right after I eat?

Diarrhea within 30 minutes of eating may indicate early dumping syndrome. This is when food moves too quickly from your stomach to your small intestine. The rapid movement triggers the release of excess hormones and fluid, triggering the release of watery stool.

Intense gastrocolic reflex causes dumping syndrome.

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Fecal incontinence can also cause an urgent need to poop. Those with incontinence can’t control their bowel movements. Sometimes stool leaks from the rectum with little to no warning.

Incontinence could range from leaking a bit of stool when passing gas to a complete loss of control over the bowels. Unlike with gastrocolic reflex, a person with incontinence might unexpectedly poop at any time, whether or not they’ve recently eaten.

Incontinence is sometimes due to muscle or nerve damage to the rectum, possibly resulting from:

Other common causes of incontinence include:

While it’s not possible to prevent gastrocolic reflex, you can take steps to make it easier to live with.

First, note when you experience the gastrocolic reflex and what you’ve eaten before it happens.

If you notice a pattern between eating certain foods and your gastrocolic reflex becoming stronger, chances are that avoiding those foods will help reduce its intensity.

Some common trigger foods include:

  • dairy
  • high fiber foods, like whole grains and vegetables
  • greasy and fatty foods, such as fries

Stress is another common trigger for gastrocolic reflex. Managing your stress can help you manage your gastrocolic reflex. Try these 16 ways to relieve stress.

Most people experience the effects of the gastrocolic reflex from time to time.

See a doctor if you experience an ongoing change in your bowel habits or if you’re constantly running to the toilet after eating. They can help you determine the underlying cause and get the proper treatment.

If you need to poop right after eating, it’s not because food is moving right through you. Needing to poop immediately after eating is typically due to an overactive gastrocolic reflux. This causes food to move through your colon more quickly.

You may experience other symptoms like abdominal pain and diarrhea. Dietary changes may help reduce the effect of gastrocolic reflex. Contact a doctor if problems persist.

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