Keeping Your GI Tract Clean and Healthy

by Ashleigh Feltham,  Accredited Practising Dietitian and Accredited Nutritionist

Do you find yourself continually snacking all day? If you want to achieve and maintain a healthy weight, this way of eating can work against you. In addition, you may not know that your stomach and gut need “cleaning breaks” between meals to stay healthy and function at their best.

The Migrating Motor Complex, also called the Inter-digestive Myoelectric Complex, happens when there is no food in the digestive system including the intestines and stomach. This complex is like the maid of your gastrointestinal system. It essentially cleans the gastrointestinal tract out using both mechanical and chemical forms of cleaning. Essentially, moving undigested food from your stomach and small intestines to your large intestines.

Girl snacking in fridge

There are three distinct phases in the Migration Motor Complex. Phase one is motor quiescence, phase two is low-amplitude contraction and phase three is strong contraction. These phases differ from contractions that happen right after a meal, called postprandial contractions, which consist of a rhythmic contraction and then a postprandial giant contraction.

One of the chemical and mechanical processes that occurs is the release of the hormone called motilin. Entero-endocrine cells, located in the upper region of the small intestine, release motilin. This hormone causes small intestine and gastric motility, which moves undigested food from the regions around the small intestine to the large intestine.

The Migrating Motor Complex needs around one and a half to two hours to go through the cleansing process. If this process is not given enough time to do its job, there can be contents remaining in your gut. This can negatively affect your health and lead to feelings of fullness early when you eat, also bloating and stomach pain. Another important reason to ensure that the Migrating Motor Complex is given enough time to perform its important role is in preventing bacterial overgrowth.

Young woman with muesli bowl, girl eating breakfast cereals nuts, pumpkin, oats and apple in bowl.

Fibre is a type of carbohydrate that the body doesn’t digest. Fibre has many important health functions, one of which includes keeping you feeling fuller for longer. This allows time for the Migrating Motor Complex to work effectively.

If your diet is formed largely from refined carbohydrates, which have minimal amounts of fibre, feelings of fullness and satiety decrease, ultimately causing all-day grazing. Making some easy swaps from refined to wholegrain carbohydrates can help keep the munchies at bay for a longer period. Try swapping refined carbohydrates for wholegrains like brown, red, or black rice, wholegrain pasta, crackers, oats, couscous, bread and quinoa.

Other good sources of fibre include vegetables, nuts, seeds, fruit, legumes and beans. Fill half of each meal with produce and one quarter with wholegrains to allow a few hours until your next meal or snack. If you choose to snack, make half of the snack a plant-based food from the good sources mentioned above.

An adult needs 25-38g of dietary fibre each day. Structuring meals and snacks as mentioned above is a good first step towards achieving your daily fibre needs.

Antibiotic Resistance

Take home message:

Including enough fibre each day is one effective way to ensure the Migrating Motor Complex has enough time to keep your gastrointestinal tract clean and healthy.



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