Lets talk about the migrating motor complex (MMC) today. Your gut has a built-in cleaning system - it is key to optimizing gut health It's essentially a cyclical wave of contractions that sweeps through your stomach and small intestine every 90-120 minutes during the fasted state. Its job is to clear residual food particles, dead cells, mucus, and bacteria from the upper gut and push them toward the colon. This is how the small intestine maintains low bacterial density (music to the ears of those with SIBO/SIFO). When the MMC works, bacteria stay where they belong. When it doesn't, they accumulate and you get a bunch of downstream issues. The MMC has three phases. Phase I - Rest. Minimal contractions. The smooth muscle resets. Phase II - Irregular contractions building in intensity. Preparing for clearance. Phase III - High-amplitude rhythmic peristaltic contractions that sweep everything forward. This is the housekeeping wave. Phase III is initiated by motilin, a peptide hormone released during fasting (STOP GRAZING). Vagal tone and enteric nervous system integrity are required for proper coordination as well - B1, B5, choline, B6 are all key. But really what I want to focus on is this very simple practical fact that the body building community especially doesn't seem to realise. Eating shuts it off. Even small caloric inputs, especially carbs or protein, immediately suppress the MMC and switch the gut into fed-state segmentation contractions optimized for digestion. Every time you snack, the cleaning cycle resets. So if you're grazing all day, the MMC never completes. Bacteria aren't cleared = They migrate upward = SIBO develops. This is also why impaired MMC function shows up as more than just bloating. Constipation, acid reflux, bile reflux, that heavy fullness sensation after eating (which is abdominal distension, not gas production). Things that disrupt the MMC: - Frequent snacking/grazing - Chronic stress (↓ vagal tone) - Opioids (got some clients who developed SIBO from this most likely) - Anticholinergics - Post-infectious enteric nerve damage (you can test for this btw - anti-vinculin antibodies. - Circadian disruption. Things that support it - Consistent meal timing - Adequate fasting windows between meals (3-4+ hours) - Intact cholinergic signalling - Proper sleep-wake rhythms - Ginger maxxing
