Let's Talk Digestion

It's time to have a talk about digestion - it's a dirty job, but someone's gotta do it. So let's go ahead and address what is actually taking place in our bodies as we inhale our food. As we talk about the trip that our food takes, below is an image to help facilitate the explanation process. Side note: While the mouth has a role in the digestion process, we are going to assume that we all know the salivary glands, teeth and tongue all work together to break the food into small pieces, and begin our discussion at the stomach.


So typically, we consume a variety of fats (which we'll discuss a little later), proteins and carbohydrates throughout the day and each of those has a different experience as it travels through our digestive system. Let's start with carbohydrates and leave the best (fats) for last.

Carbohydrates: Digestion begins in the upper area of the stomach (the storage area). As it travels to the lower part of the stomach, an enzyme in conjunction with hydrochloric acid inside stops the digestion of starch. As it moves through the pancreas, it is pushed into the small intestine with the help of a starch-digesting enzyme. Absorption of the food fragments occurs as the cells in the intestinal lining go to work and break down those starch and sugar fragments. (Sizer & Whitney, 2011, p. 85)

Proteins: Protein must be broken down and to do that the stomach calls on the same hydrochloric acid to aid in "uncoiling" the protein strands and to "activate" the digesting enzymes. (Sizer & Whitney, 2011, p. 85) Utilizing the enzyme is what helps to take the strands and breaks them into smaller pieces. While moving through the pancreas and small intestine, an enzyme breaks them into even smaller fragments or "free amino acids." (Sizer & Whitney, 2011, p. 85) The free amino acids are absorbed, but some of the fragments that aren't transformed into free amino acids are taken into the large intestine where it is typically excreted.

Fats: "Fat is last to leave the stomach" and additionally not all fat is digested. (Sizer & Whitney, 2011, p. 85) The fat in our stomach will actually separate from the other fragments and float above it all. A lot of the work is done within the pancreas, liver and small intestine. In an effort to not miss a step, I will take this step directly from the text. "The liver secretes bile, the gallbladder stores it and releases it into the small intestine. Bile emulsifies the fat and readies it for enzyme action. The pancreas produces fat-digesting enzymes and releases them into the small intestine to split fats into their component parts (primarily fatty acids), which then are absorbed." (Sizer & Whitney, 2011, p. 85) Those that aren't absorbed are excreted.

In understanding the way our body processes our food, we can each be much more accountable of what we decide to put in our mouth knowing that that choice in food will have a direct effect on our body's digestive system and health.

Before discussing fats and why we love them so much, let's take a quick look at fiber and why its an important element in our diets. There are two types of fibers that many of us are familiar with - soluble and insoluble. Soluble dissolves in water, while insoluble does not dissolve in water. Soluble fiber is said to affect blood sugar levels (obviously aiding in the control of diabetes) and delays the stomach from emptying - to give you more of the full effect. Foods with soluble fiber include fruits (berries), some nuts and vegetables. Insoluble fibers do much the opposite, they speed up the digestive tract and aid in preventing constipation. These fibers are found primarily in vegetables and grains. (Fuhrman, 2011)

Okay, so the best part for last - let's talk fat. There's always big debate on the types of fat that should be consumed, let alone whether they should be eaten at all. We've already gotten pretty technical in terms of our digestive system, so in an effort not to lose your attention, we won't go into all the nitty gritty details of fats, but we will address what constitutes a good fat and a bad fat and please take into consideration a healthy active lifestyle is recommended as well.

Good fats: Some oils (olive and coconut) Avocado (high in omega-3: good for brain & heart health), some nuts, meat and fish.

Bad fats: Highly saturated fats such as fried foods (french fries, donuts, fried chicken, etc.), and foods high in high glycemic carbohydrates which are processed and stored as fat.

The main thing to remember, is that we need NOT to steer clear of fats, as our body needs fat in order for our body release excess fat; otherwise our body will retain what it has thus resulting in that beautiful tire carried around the midsection.

References:

Fuhrman, E. (2011) Digestion aids expand beyond regularity. Beverage Industry, 102(3), 50-53.  Retrieved September 13, 2011, from ABI/INFORM Global. (Document ID: 2293541111).

Sizer, F. & Whitney, E. (2011) Nutrition: Concepts and controversies. (12th edition) Belmont, California: Wadsworth, Cengage Learning.