Understanding how the digestive system works and what can go wrong in the digestive process is how we can then know how to improve digestion and gut health.
What is Digestion?
Simply put digestion is the process of breaking down the food we eat so that we can absorb and utilize the nutrients found within food while eliminating what is not used or needed by the body. Having optimal digestive function is key to optimal health as we need the ability to break down and absorb nutrients from food which are required as co-factors for all of the bio-chemical processes in the body. When the body lacks nutrients health can worsen due to the cells of the body lacking nutrients that are needed to function on a cellular level. Cellular dysfunction ripples out to organ dysfunction to system dysfunction to you guessed it..... symptoms of poor health, but it all starts with the diet and the ability to digest and absorb the nutrients in food.
Where does digestion begin?
Digestion is a north to south process that begins in the brain and ends with feces being eliminated. It is the thought and smell of food that stimulates our digestive juices and gets them flowing along with saliva production in the mouth. Good digestion and secretion of all the necessary digestive juices and processes require the body to be in a parasympathetic nervous system state.
Many individuals are eating on the run or when they are stressed out and as a result are not properly digesting their foods. This can be one of the first reasons as to why someone is having digestive complaints so before we talk about anything else lets be sure to get our digestion off to a good start by taking a deep breath, sitting down and enjoying our food in a relaxed manner.
Salivary glands function in the digestive system
In the mouth is where both the mechanical and chemical breakdown of the food begins. It is very important to thoroughly chew your food through the mechanical breakdown and mix the food with saliva for the chemical breakdown of starches and carbohydrates. The salivary glands function is to produce saliva which contains an enzyme called amylase that acts immediately on breaking down the carbohydrates found within the food but it needs time to act which is why chewing thoroughly is important.
Aiming to chew 30 times per mouthful is an inexpensive way to ensure good digestion. If food is not initially properly chewed it puts strain on the organs further down and can lead to problems such as strain on the pancreas in which the digestive enzymes of the pancreas are unable to fully breakdown the food that was not properly chewed. The undigested starch and carbohydrates are food for candida and can contribute to dysbiosis of the gut flora and a leaky gut.
What is the main function of the stomach?
2 main functions of the stomach is to begin the breakdown of protein and to sterilize food by killing any harmful pathogens that may be found in the food. Pathogens and parasites that enter the body via food or water can wreak a lot of havoc while promoting inflammation in the body if not destroyed by stomach acid.
When food enters the stomach this is where protein digestion begins. The stomach mechanically mixes the food with the stomach acid HCL through muscular contractions while chemical digestion of protein takes place through HCL being secreted to acidify the food and activate the enzyme pepsin to break the protein down into polypeptides and amino acids.
The acidity of the stomach acid also acts as a fist defense against harmful organisms in which pathogens, parasites, viruses, fungi etc are killed by the acidity of the stomach. If the stomach acid is not acidic enough these pathogens can take up residence further down the digestive tract wreaking havoc and causing discomfort.
Many people do not have sufficient stomach acid which is a common reason for digestive complaints and nutritional deficiencies. When the food is properly acidified and the protein has been broken down it passes through the pyloric sphincter and into the top part of the small intestine called the duodenum.
Pancreas function in the digestive system
In the duodenum it is the acidity of the chyme (food) that triggers the hormone secretin to stimulate the pancreas to release sodium bicarbonate to raise the pH of the chyme to neutral along with releasing digestive enzymes that further help to finish the digestion of the proteins, fats and carbohydrates. If the chyme is not properly acidified it will not act as a trigger for the pancreas to release sufficient digestive juices which then can result in the acidic chyme burning the mucosal lining (as it is still acidic just not enough) along with the enzymes not being released causing insufficient breakdown and therefore insufficient absorption of nutrients.
Gallbladder function in the digestive system
If fats are present in the chyme the hormone CCK stimulates the gallbladder to contract and release bile which is needed to emulsify the fats so that the pancreatic enzyme lipase can have more surface area to complete the breakdown of fats into fatty acids. If fats are not included in the diet, the bile can become thick and viscious resulting in impaired bile flow and fat breakdown. The bad fats including refined vegetable oils and hydrogenated fats will also cause the bile to become thick and vicious.
Bile is also antimicrobial and helps to clean the small intestine, thus preventing overgrowth of bacteria as in the case with SIBO. Many digestive complaints are linked to SIBO with the root of the problem being linked to poor bile production and flow.
For optimal digestion function it is very critical that we have appropriate stomach acid levels along with good bile flow and enzyme secretion from the pancreas to properly digest and breakdown protein into amino acids and peptides, fats into fatty acids and carbohydrates into glucose which can then be absorbed by the small intestine along with all the vitamins and minerals to fuel the body and supply the nutrition needed for the body to function and maintain health and vitality.
The small intestine is lined with millions of microvilli that are fingerlike projections that allow for the absorption of nutrients, glucose, amino acids and short chain fatty acids that are carried by the villi to the capillaries and into the liver. The intestinal lining is also selectively permeable which means that it only allows nutrients in while keeping waste out.
If foods are not properly broken down in the mouth, stomach and duodenum with the help of chewing, HCL, pepsin, bile and pancreatic enzymes this can result in undigested foods impacting the villi and integrity of the gut lining in which selective permeability is lost and the gut lining becomes leaky.
A leaky gut allows undigested food to pass through the lining and into our bloodstream. As the food is not properly broken down the body does not recognize the undigested food as a nutrient that can be used by the body and instead thinks that it is a foreign invader.
The immune system then mounts an attack on the undigested food by producing antibodies against what would have been a nourishing food if only properly broken down in the first place. Food sensitivities and intolerances can be created through the production of antibodies against undigested foods that have passed through a compromised gut lining.
Whatever is left over from the small intestine such as indigestible fibers, bile and water then passes through the ileocecal valve and into the large intestine. The large intestine is responsible for recycling water and capturing any lost nutrients that is converted into vitamins k, B1, B2, B12 with the help of beneficial bowel flora.
The large intestine also forms and expels feces which is very important as we do not want to be holding on to waste. Obtaining fiber in the diet and having good bile flow is important as the fiber is what absorbs the bile and bulks up the stool while the bile stimulates peristalsis to move food and waste along the digestive tract and out of the body. Daily bowel movements and elimination of waste is necessary for a healthy digestive system.
From a functional point of view the primary organs involved in digestion are the stomach, pancreas and gallbladder. If any of these primary organs involved in upper digestive function are not working properly a host of digestive symptoms can occur. Before jumping into "treating digestive symptoms," instead look to what primary organ in digestion is not working optimally and how you can support that organ involved in digestion.
How to improve digestion
My primary supplements to improve digestion include betaine HCL for optimizing stomach acid (work with a practitioner to use this properly and ensure no contraindications)
Digestive Enzymes to help support the pancreas with additional enzymes to break down all food.
Gallbladder nutrients to support bile flow from the gallbladder and aid in fat digestion.
Sometimes healing and soothing nutrients need to be taken prior to optimizing digestive function. Optimal GI by seeking health is an amazing blend with gut healing nutrients and herbs to soothe the intestinal lining, calm inflammation and support repair of the gut lining.
Do you experience digestive "symptoms" and would like to find out what dysfunction may be underneath the symptom and how to best support the body? I specialize in optimizing digestive function and would love to help.
If you would like to learn more about how to improve digestion I highly recommend reading Digestive Wellness by Elizabeth Lipski. This book was one of the first books I read on digestive health and I still consider it my digestive bible as it is filled with such useful information and and easy to implement steps to get you started on improving your digestive health today!
Hey! I'm Amber, a nutritional therapy consultant helping people to improve digestion, beat the bloat and lose weight. Sharing weight loss tips, gut health tips and whole food recipes that are gluten free. Grab your freebie below:)
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