Migrating Motor Complex MMC and SIBO

There is a close connection between Migrating Motor Complex MMC and SIBO

What is Migrating Motor Complex MMC? Your digestive system gets rid of waste through a process known as the migrating motor complex. There is a cycle of the peristalsis of the gut. This happens every two hours.

There are 4 phases in the MMC Migrating Motor Complex cycle

1st phase: It lasts 45 to 60 minutes
The first phase is a period of intestinal smooth muscle calmness which only rare action potentials and contractions occur.

2nd phase: Lasts about 30 minutes .
The peristaltic contractions take place and slowly increase in frequency. Peristalsis starts in the stomach and continues throughout the small intestine.

3rd phase: It lasts 5 to 15 minutes.
There are rapid, evenly spaced peristaltic contractions. During these peristaltic contractions the pylorus remains open and this permits many indigestible materials to pass into the small intestine.

4th phase: Short time
This is a short period of transition between the strong contractions that happen in the third phase and the inactivity that happens in the first phase.

During MMC. the migrating motor complex, increased gastric, biliary, and pancreatic secretion take place to help further digestion and decrease bacterial buildup in the proximal segments of the digestive tract.

We think that the MMC is controlled by the enteric hormone motilin.

Ingestion of food overrides the MMC. That’s why fasting has to happen on a regular basis to help complete the process.

The typical “growling” sounds you hear when you are hungry could very well be the MMC at work, cleaning your bowels of waste and excessive bacteria through increased peristalsis.

As many as 70% of people who have SIBO experience a disruption of MMC rhythm.

Excessive methane / hydrogen gasses produced by overgrowth of bacteria in the small intestine has been linked to decreased Migrating Motor Complex MMC function.

What happens is that when the second and third phase of the MMC is lessened, bacteria remains in the small intestine instead of being pushed back into the large intestine.

Bacteria are then able to grow in the small intestine, which increases inflammation and intestinal permeability.

Inhibition of MMC homeostasis drives the vicious SIBO cycle.

What leads to Poor MMC Function?

  • Reduction of stomach acid by using acid reducing medications or H. pylori infection can result in poor MMC function.
  • Lack of exercise, grazing, and constipation can also contribute to poor MMC function.
  • Being over stressed and anxious can also decrease MMC function.
  • Low thyroid function and adrenal fatigue can lower MMC function.

Fasting for at least four hours after meals during SIBO protocols might be beneficial in re-regulating the MMC.

The increase in fasting time gives your body longer time to complete the Migrating Motor Complex MMC process.

MMC also occurs during sleep, which proper sleep may be more helpful because of the longer total fasting time that normally occurs during sleep.

Frequent exercise also helps to regulate the Migrating Motor Complex MMC properly.