Did you know your gut has its own “housekeeping” system called the migrating motor complex (MMC)?
Knowing more about this interesting mechanism will help us understand the best way to eat for gut health. Are small, frequent meals and snacks best or should we aim for three bigger meals a day?
Let’s find out.
What is the Migrating Motor Complex?
Your body has its own gut-cleansing system called the migrating motor complex (MMC).
The MMC is designed to move matter through your digestive tract. (1) Pushing food and other particles through the gut, the migrating motor complex keeps you regular and helps to prevent gut infections like SIBO (small intestinal bacterial overgrowth). (2) It’s a crucial component of any healthy digestive tract.
Why is the Migrating Motor Complex So Important?
The MMC stimulates peristalsis, the movements of your intestinal muscles that move food through your digestive system and (eventually) help you go to the bathroom. (1)
Going to the bathroom regularly is obviously very important, but the MMC does even more for you: it also helps to prevent infections and bacterial overgrowth in the gut. (2) An impaired MMC (i.e. an MMC that isn’t doing its normal cleaning duties) gives gastrointestinal infections an opportunity to take hold in your gut -- no thanks! (3)
The cleansing capabilities of the MMC are highly important in keeping your digestive system functioning normally. But there’s a catch!
The MMC only works when you’re not eating. During digestion, your body needs to focus on just that: breaking down your food. It can only clean up when it’s not digesting.
The migrating motor complex does its job in approximately 60 to 120-minute cycles, though some research indicates the process may take up to 90-230 minutes. It’s a four-phase process consisting of different contraction rates in the stomach and small intestine that repeat until your next meal.
So how does this affect how you should eat to optimize digestion?
How to Optimize Your Migrating Motor Complex for Better Digestive Health
Clearly, cleaning up shop is key to a healthy, well-functioning digestive system. So how do we keep our cleansing machine, the MMC, doing its job?
First, incorporate some degree of fasting. Since the MMC only gets the opportunity to do its job when it’s not busy breaking down food, space your meals out by at least three to five hours and incorporate an overnight fast of at least 12 hours.
For example, if you eat breakfast at 8 AM, wait until at least 11 AM to have lunch or a snack. And if you eat dinner at 8 PM, wait until 8 AM to have breakfast - a solidly long 12 hour period for the MMC to get to work. Pretty simple, right?
This doesn’t necessarily mean you need to incorporate super long degrees of fasting, like intermittent fasting (putting off your first meal until later in the day). It just means you need to incorporate pockets of fasting within your routine to allow the MMC to do its job. It even means you can still snack, provided that you’re giving your body periods of 3-5 hours of fasting between meals and snacks.
Reducing stress is key to promoting proper MMC function. We know, we know, you’ve heard this one before. But the stress hormone cortisol can inhibit the MMC from doing its job, so incorporating stress management techniques like meditation or deep breathing can help your migrating motor complex function well, too. (4)
Lastly, the MMC may become impaired in those with gut infections -- patients with SIBO or IBS show decreased MMC activity. But the good news is that clearing gut infections may restore some of the MMC’s activity. (5) Make sure you’re working with a healthcare provider to address any gut infections!
The Bottom Line: The Migrating Motor Complex & Digestion
The migrating motor complex (MMC) is your GI tract’s housekeeper - it cleanses potentially harmful pathogens from the gut and keeps you regular by pushing material through the gut.
But it only gets to work when you’re not digesting. For that reason, spreading your meals and snacks out by 3-5 hours and fasting overnight for 12 hours allows the MMC to do its job and keep your digestive system in tip-top shape!
- “Migrating Motor Complex.” Migrating Motor Complex - an Overview | ScienceDirect Topics, 2020, www.sciencedirect.com/topics/medicine-and-dentistry/migrating-motor-complex.
- Salem, Ahmed, and Bandi Chander Ronald. “Small Intestinal Bacterial Overgrowth.” ResearchGate, 2014, www.researchgate.net/profile/Ahmed_Salem44/publication/269994398_Small_Intestinal_Bacterial_Overgrowth_SIBO/links/549d85860cf2b803713a783f.pdf.
- Vantrappen, G., et al. “The Interdigestive Motor Complex of Normal Subjects and Patients with Bacterial Overgrowth of the Small Intestine.” The Journal of Clinical Investigation, American Society for Clinical Investigation, 1 June 1977, www.jci.org/articles/view/108740.
- Valori, R.M., et al. “Effects of Different Types of Stress and of ‘Prokinetic’ Drugs on the Control of the Fasting Motor Complex in Humans.” Gastroenterology, W.B. Saunders, 10 June 2016, www.sciencedirect.com/science/article/abs/pii/0016508586902581.
- Pimentel M;Soffer EE;Chow EJ;Kong Y;Lin HC; “Lower Frequency of MMC Is Found in IBS Subjects with Abnormal Lactulose Breath Test, Suggesting Bacterial Overgrowth.” Digestive Diseases and Sciences, U.S. National Library of Medicine, 2002, pubmed.ncbi.nlm.nih.gov/12498278/.