Motilin

What is motilin?

Motilin is a type of gastrointestinal hormone. Your body releases motilin to help move food from your small intestine to your large intestine. This movement of food through your digestive tract is called the migrating motor complex (MMC).

Your body releases motilin throughout the day. You produce more motilin during fasting periods (when you aren’t eating), such as between meals or during sleep.

Your motilin hormone levels also vary depending on what you eat. For example, motilin decreases when you eat foods with fat or sugar (glucose).

What is the purpose of motilin?

Motilin’s primary function is to move food through your gastrointestinal tract. Motilin also helps produce a stomach enzyme called pepsin. Pepsin helps your body digest protein.

When your body releases motilin, it binds to cells called motilin receptors. As motilin binds to receptors, the muscles in your small intestine contract. This action moves food to the next stage of digestion.

How does motilin function with the migrating motor complex?

Motilin regulates the migrating motor complex. When your body releases motilin, it activates the MMC. The MMC:

• Transports undigested food from your small to your large intestine.
• Moves bacteria from your small intestine to your large intestine to prevent bacteria overgrowth.
• Keeps bacteria from traveling backward from your large intestine to the last part of your small intestine (terminal ileum).
• Makes sure that no leftover food or bacteria blocks nutrient absorption.

How does motilin affect other body functions?

When your body releases motilin, it also acts on other parts of your body. Motilin helps trigger:

• Gallbladder emptying.
• Hunger cues, along with ghrelin.
• Release of insulin, the hormone that helps your body process sugar, from your pancreas.

What conditions and disorders affect motilin?

Some conditions can affect your motilin levels. For example, studies have shown that pregnant people typically have lower motilin than people who aren't pregnant. Decreased motilin can cause pregnant people to experience constipation and heartburn.

Low motilin

Low motilin can also cause hypomotility, or slowed muscle contractions and movement in your digestive tract. Certain gastrointestinal diseases are associated with hypomotility, including:

• Chronic constipation.
• Functional dyspepsia.
• Gastroparesis.
• Intestinal pseudo-obstruction.
• Irritable bowel syndrome (IBS).

High motilin

High motilin can cause faster-than-usual food movement and more intestinal contractions. Conditions associated with high motilin include:

• Diabetes.
• Ulcerative colitis.

How can I keep my motilin levels and digestive system healthy?

You can increase the health of your digestive system and hormones by practicing healthy lifestyle habits. You may:

• Aim for at least seven hours of high-quality sleep per night.
• Drink plenty of water, about 3 to 4 liters per day, depending on your size, sex and activity levels.
• Eat a variety of fruits, vegetables and whole grains.
• Exercise consistently, incorporating strength training, stretching and aerobic exercise.
• Quit smoking and using tobacco products, and limit your intake of caffeine, alcohol and processed foods.
• Use antibiotics only as necessary and avoid antibiotic overuse.

Why is motilin secreted during fasting?

The migrating motor complex or MMC is timed to help your body move food through your digestive tract. Motilin is part of the MMC.

As you eat, stomach enzymes are secreted to start the process of breaking down food. Your body releases motilin after your stomach has had time to begin breaking down the food. This is the last phase of this process which happens when you are fasting (the time in between meals). The undigested food moves from your stomach into your small intestine.

What hormones stimulate gastric emptying?

Gastric emptying is the process of moving food from your stomach to the first part of your small intestine (duodenum). Ghrelin and motilin stimulate gastric emptying.

Where are motilin receptors located?

You have motilin receptors along your digestive tract. Your digestive tract includes your:

• Stomach.
• Small bowel.
• Colon.

Motilin receptors are most concentrated in a narrow part of your stomach called the pyloric antrum. The pyloric antrum is the first part of the pylorus, the opening between your stomach and small intestine.

A note from Cleveland Clinic

Motilin is a hormone that stimulates your digestive system. It helps move food from your small intestine to your large intestine. Motilin also plays a role in controlling insulin release and triggering hunger cues. If you have low motilin, you may have slow or delayed muscle contractions in your small intestine.