In this blog I talk about food and nutrition a lot but we don’t get into how we digest it all the often. So today we are going to focus on the way we digest our food and how this process is broken and can be fixed. If I were to ask you where digestion starts many people would say the stomach. A few less would say the mouth. They would all be wrong. The correct answer is your mind. That’s right! Digestion of our food starts in our minds.
There are three phases to our digestion. The first is the “Cephalic Phase” (Cephalic means head) which is where we think about food. It may sound silly but this is actually the first step. Thinking about a meal, whether it’s planning what to make or choosing from a menu, stimulates the production of acid in our stomachs and starts the production of digestive enzymes in the pancreas. This effect continues in the mouth as the stimulation of the tastebuds tells the stomach and pancreas what the approximate nutrient make-up of the food is. That allows our digestive tract to be better prepared for what is heading its way and digest it fully.
The problems we run into in the Cephalic Phase are more sociological than physiological. In society we have become distracted from our nutrition and food as well as demanding shorter wait times for our food. These have limited the impact of the Cephalic Phase on our digestive abilities because we are now watching TV or working at our desks while eating rather than focusing on the food in front of us. Studies have shown that a dinner around a table with family and friends or sitting on a park bench alone will be digested and absorbed better than those in front of a screen. As well, the shorter waiting times for food have decreased our anticipation of the sustenance thus decreasing our time spent getting the salivary enzymes, stomach acid, and pancreatic enzymes primed and ready for food.
Being more mindful and purposeful in what and how we eat will serve us well when it comes to digestion and the nutrients we receive.
The second phase of digestion is the “Gastric Phase” (Gastric means stomach). After we chew and swallow our food it makes its way down into the stomach where it is churned around like it’s on tumble dry. Acid and a few enzymes are excreted by the stomach wall to chemically breakdown the food particles and the stomach walls rhythmically contract to help out by mechanically breaking up the food and mixing it with the acid and enzymes. As the solid food is digested into a more liquid state it gets pushed out of the end of the stomach and into the small intestine.
The main problem we encounter in the Gastric Phase of digestion is well known as Acid Reflux (Gastro-Esophageal Reflux Disorder – “GERD”). GERD is often thought of as the over production of acid during a meal, which it can be, but many experts believe that it is much more common to have an under production of acid in the stomach which causes the burning sensation of Acid Reflux. The body is filled with sensory tissues that feed back to regulate activities throughout the body. As the food exits the stomach and lands in the intestines it hits a patch of such sensory tissues. They judge the acidity of the food and let the pancreas know how much base to add to neutralize it so that the lining of the intestines is not damaged. It also tells the stomach if there is not enough acid or only partially digested food coming out of the stomach which causes the stomach to produce more acid. All in all it’s a fairly simple system but when the last of the food passes out of the stomach then stimulating the stomach to produce more acid we come upon the problem. The acid is churned around and can push out the upper end of the stomach causing acid reflux. So this issue bridges the Cephalic Phase where we should be producing the acid needed but we have truncated this process and the Gastric Phase where we should be using the acid provided previously.
Taking more time to focus on and enjoy our food more will help to alleviate the distress of GERD as well as a shot glass of vinegar immediately before eating which will provide some acid for the stomach and aid the chemical digestion when acid production is low.
The other problem associated with the Gastric Phase of digestion is Ulcers, which are damaged of the lining of the stomach by the acid it secretes. Normally, the stomach lining is protected by a layer of mucus that is maintained to buffer the acid that approaches the stomach wall. Ulcers can occur when the mucus is not maintained or when the acid is produced in greater quantities than needed, which is the less likely of the two. Mucus can be degraded by outside influences (like bacterial infections) or internal functions like stress. Taking time for ourselves is always a good idea because stress has such a strong influence on our health. Also, a well balanced diet will help to maintain a good mucus layer to protect against damage.
The final phase of digestion is the “Intestinal Phase” which is where the vast majority of the nutrient absorption happens. When the partially digested food passes into the intestines it is dosed with an amount of base to neutralize the acid of the stomach, a good portion of digestive enzymes, and enough bile to mix in with the fats in the food for easier digestion and absorption. This mess of stuff gets passed along the intestines as the excreted chemicals work away at the food. Nutrients are absorbed in the small intestine leaving mostly water and fibre and waste products for the large intestine. In the large intestine the water is reabsorbed as needed and our gut bacteria get to work on the fibre digesting it and passing on the absorbable sugars to us.
The things that can go wrong in the intestines can fill a textbook all by themselves so I want to focus on the two simpler problems that affect most people in the world. Constipation and Diarrhea can range from chronic problems to occasional irritants. Most diarrhea is caused by some irritant in the bowels that our body is trying to get rid of quickly but this is not the type of diarrhea I am talking about today. Today I want to focus on loose watery bowel movements that have very little substance to them. This type of diarrhea is not caused by irritation but by diet. Constipation is the other end of this spectrum and can just as equally be caused by diet. The main factors here are fibre and water. The balance of these two is very important for the ease and health of our poop. Fibre holds our feces together providing structure but also trapping toxins and chemicals inside so that they are not absorbed as easily. Water keeps the intestinal contents soft and flowing. If we don’t have enough fibre in our diets we can, depending on what our diet consists of, get stopped up or have watery stool, neither of which is a great situation to be in, and water allows the fibre to move along as well as help with nutrient retrieval from within the fibre tangle. Fibre in our diet can also help to lower cholesterol.
Constipation can also be the result of imbalance between the two sides of our involuntary nervous system; the Sympathetic (Fight or Flight) and the Parasympathetic (Rest and Digest). In our world of non-stop stimulation and activity we are all Sympathetic dominant if we don’t actively try to balance ourselves. This means that our Parasympathetic stimulation is lower than it should be and this means there is less movement of the intestinal muscles. Deep breathing exercises, walking, and sipping water throughout the day will stimulate the Parasympathetics as well as activities like meditation and yoga.
I know that this was a long post this week and I hope that makes up for missing that last two. Thanks for hanging in with me. The best things we can do with our digestion is to slow down, focus on our food more, and take some time for ourselves to just breath and relax every day.
As always, thanks for reading and happy eating.