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Small Intestine: Processing & Absorbing Nutrients

Intro to Your Small Intestine

Now we look at possibly the most amazing station of the entire digestive system. As discussed earlier, everything that happens to what we eat takes place “outside the body” until it arrives in the small intestine. Here is where the transfer of the outside nutrients actually takes place.

Once the food is broken down into small enough particles, your small intestine determines which particles of the chyme to absorb and which particles to reject.Only when these nutritive elements are absorbed through the walls of the small intestine does the food officially enter “inside the body.”

What remains in the small intestine is waste or roughage (still “outside” the body), which it passes through to the large intestine for elimination.

As your primary protector, the action of the small intestine determines what is helpful and what is harmful, or simply not useful, to the system.The small intestine is the organ most responsible for your nutritional intake.

Anatomy of Your Small Intestine

The small intestine is the part of the gastrointestinal tube between the stomach and the large intestine. In adults, it is about 21 feet long.

Most of the nutrients from ingested food are absorbed within the first third of the small intestine. To enable this miracle of absorption, the walls of the small intestine (the gut wall) are covered with millions of finger-like extensions called villi.

The villi provide a massive contact surface for the chewed particles of food to be processed and slipped through its wall into the blood vessel that will carry them to the liver. These life or death decisions are made on a particle-by-particle basis at the level of a single cell.

The gut wall, the actual inside wall covered with the mucosal membrane that is in contact with the “outside” environment, has an essential job. Not only must it perform the final breakdown of what you eat or drink, it is responsible as the gatekeeper to allow only good things into your bloodstream.

At the simplest level, the small intestine has three functions:

  1. Finalize the enzymatic and chemical breakdown of your food into nutritional particles
  2. Absorb the processed particles through its walls into the bloodstream
  3. Prevent the intake of toxins and digestive waste materials and then pass these by-products on to the large intestine

The waste products of digestion include undigested parts of the food known as fiber. Also, there are the older cells that have been shed from the walls of the small intestine. These “first defense” cells in the small intestine have a high turnover rate so they can continue to function at an optimal level.

What is Another Anatomical Condition Related to the Small Intestine

If you have paid attention at all to digestive related news, you will probably have heard of a recent digestive problem that is making headlines and changing the health food world. This is the idea of eating Gluten Free.

Gluten is a protein associated with wheat, barley, and rye. The premise is there is a certain percentage of the population that has a genetic problem with the villi. For these people their villi are genetically unable to process and absorb the gluten molecule.

This is a genetic/anatomical condition. If you have noticed that after you eat a wheat meal, that your belly swells up like you are pregnant starting around the belly button area, this is a classic indicator of gluten problems.

There are an increasing number of diet books and cookbooks that teach you to transition to foods that don’t include gluten. The problem however, is that gluten is a very common food additive because it makes things thick and sticky, (like gravy) and is added to all sorts of things like catsup or ice cream and you could never know.

If you have any of the classic symptoms related to the Small Intestine, going “gluten free” is the most direct way to see if your symptoms change. If you have the gluten problem, then you have to make the changes or you will continue to experience your symptoms.

What Are the Typical Symptoms of Your Small Intestine?

Symptoms directly attributable to the small intestine and no other organ are difficult to isolate. Typically, small intestinal problems can derive from a problem with the other stations, for example, the stomach or issues with the “squirting” of the pancreas or gallbladder.

The small intestine also reacts when there is back flow from the bowel (as discussed next chapter). To make a list, I would start with:

  • Nausea or cramping, that seems to be coming from the belly button area or just above
  • Bloating, that puffs out the middle of your belly “like you are pregnant”
  • Gas or wind that doesn’t smell, especially you experience this first thing in the morning

These are the kinds of problems you would experience if you were perfectly following all the other guidelines of the Digestive Awareness Diet.

The easiest (and free) way to tell if you are having a potential problem with gluten is to make a point of not eating any gluten at ALL (admittedly hard to do) for 5 days to a week. See if your symptoms seem to improve.

What typically happens is you “feel better” over the few days it takes for your sensitivity to reduce but even still you don’t connect it to gluten. So, after a week of no gluten, then help yourself to a meal of bread, or pasta, or whatever you were craving as your body was detoxing for the week.

Then, if you get “knocked out” by a sudden immediate return of all your symptoms, you have a positive diagnosis.

Brain Management For Your Small Intestine

Follow all the prior principles of the Digestive Awareness Diet, and the small intestine will do its job without much fuss or bother, IF you don't have the "gluten sensitively" mentioned earlier.

The most important factor of the Small Intestine is whether or not you are sensitive to gluten because it is a genetic problem. Check to see if you "feel bloated" after you eat a meal containing lots of wheat.

If this is a problem for you, you will have to eat what’s called a “gluten free” diet which is somewhat tricky to learn about, but there are many resources and books, including gluten free cook books, to help you with these lifestyle changes.

However, if you:

  1. Chew your food
  2. Take apple cider vinegar and/or enzymes
  3. Don't abuse your digestive system with junky foods

Your small intestine is usually able to take care of itself. If this is not enough, eating gluten free is your answer. 

At the end of the small intestine however, comes the digestive problem that is probably the most misdiagnosed, misunderstood, and least known culprit for what is possibly the worst overall digestive problem that can occur in human beings.

This part of the digestive tube is known as the ileocecal valve, and for the majority of people suffering from the ravages of poor digestion, there’s much to know. This is one aspect of knowledge that you will never find in any other course of study about digestive function, because only Chiropractors know about this problem.