Digestion Top to Bottom – Assimilation

Remember this picture?

A few weeks ago, we posted about the basics of the Top to Bottom process of Digestion. We also included the basics of the Ingestion and  some steps  you can take to improve the ingestion of the foods you eat. You can read up on the article here.

After you ingest your foods, they move down through your body on quite a journey that includes a lot of chemical reactions and transformations. In fact, the saying about mixing foods that “it will all end up in the same place” is actually only partly true.

When you swallow your food, it becomes what’s called bolus and it enters the esophagus en route to the stomach. The stomach secretes gastric juices from millions of tiny gastric glands that are found in the mucosal lining of the stomach. These gastric juices are made up of mucous, the proenzyme pepsinogen which converts to the enzyme pepsin, and hydrochloric acid (HCl). Together, HCl and pepsinogen begin to break down the proteins into smaller strings of amino acids.

The stomach needs to be very acidic to ensure this process runs smoothly. When the HCl is excreted into the stomach, its pH is 0.8 – that’s almost pure acid! The acid plays many important roles including:

  • Disinfecting the stomach
  • Killing bacteria and parasites
  • Activating pepsin so we can break down proteins and digest them
  • Stimulating gastrin

So – what’s gastrin? Gastrin is a hormone that is triggered by HCl to release into the bloodstream and increase stomach contractions. These contractions help to churn and mechanically breakdown the bolus further.

Food —> bolus —> bolus + gastric juices = chyme

Chyme is a very acidic paste that is released into the small intestine. The chyme has to be very acidic as it leaves the stomach so it can trigger the small intestine to secrete mucous to move the chyme along. The hormones secretin and cholecystokinin (CCK) are also secreted at this point.

By the time the chyme enters the small intestine, it’s pretty much completely digested. 

  • Carbohydrates are broken down into glucose molecules
  • Proteins are broken down into amino acids and polypeptides
  • Fats are broken down into fatty acids and glycerol molecules

What’s important about this is that these simple nutrient molecules from the foods we’ve eaten are recognized by our cells! Our cells do not recognize broccoli or hamburger, but they do recognize glucose molecules and amino acids!! Millions of villi and microvilli along the wall of the small intestine absorb these nutrient molecules into the bloodstream where they are carried and used by the entire body.

As you may have already figured out, this is not such an easy process (and I’ve only given the highlights). We should thank our bodies each and every day for taking us through this process! Unfortunately, there are quite a few sticky points along the way. 

1.  Approximately 90% of Americans produce TOO LITTLE HCl. Low stomach acid (NOT HIGH) causes heartburn, or GERD. If there is not enough acid in the stomach, foods do not get broken down (carbs ferment, fats go rancid, proteins putrefy). These poorly digested foods cause a reflux (backward flow) into the esophagus. The esophagus is sensitive to the acidic foods, causing pain.

  • Reduce stressors in your life. The ones that put you on edge
  • Eliminate refined carbohydrates and increase quality fats
  • Ensure you are eating more diverse, nutrient rich foods rather than fast-foods or poor quality foods
  • See if there are certain foods that trigger allergies, bloating or unease and try eliminating them for a while to see if you feel better
  • Try not to drink many liquids directly before or with food time
  • Avoid chewing gum. The action of chewing makes your body believe that food is coming and when it isn’t
  • Apple cider vinegar is an awesome supplement for many different things, including helping with digestion. Add a tablespoon to a glass of water. You can also buy HCl supplements to aid in your production 

2. Your gallbladder does not function correctly so your fats are not broken down effectively.

  • Ensure you include high-quality fats in your diet and avoid foods that are produced to be low-fat or fat-free
  • If you need to, you can also supplement bile salts into your diet to help with the liver’s production of bile 

3. Leaky gut syndrome – Undigested proteins and other foods impact the ability of the villi and microvilli to absorb the micro nutrients. The lining becomes leaky as the selectivity of what can pass into the blood stream is lost and overwhelms the immune system.

  • See the above recommendations. They will all help with leaky gut syndrome
  • Increase your good bacterias – or probiotics. This can come in the form of fermented foods and drinks or through oral supplements such as VSL #3.
  • If you’d like a really good, all around prebiotic, probiotic, and digestive enzyme, I recommend Digestion Plus


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