Most people with IBS report fatigue one of the common IBS symptoms. The human digestive tract is a large & complex system. Most of our internal organs are devoted to the process of digestion. The majority of the digestive tract is made up of long tubular muscles which are found in the esophagus, small intestine, large intestine & colon. These muscle take a large amount of energy to do their work.
When the digestive tract is not functioning properly it will often make us feel fatigued. There are few factors as to why this is. Those with the diarrhea predominant IBS may have an overactive intestinal tract, causing it to use more energy. Those with constipation predominant IBS may have issues with their body being able to rid itself of toxins within the stool that has become stuck in their system. Plus those with constipation will have to work harder to pass stool. Anyone with IBS will likely have to deal with the digestive tract cramping or spasms which will cause fatigue due to energy consumption & signals of discomfort being relayed to the brain.
The digestive tract also holds the majority of our serotonin supply. Serotonin is an important factor in moderating our moods. If our digestive tract is not functioning properly it may interfere with our serotonin levels making someone more prone to moodiness or depression. Lastly those with IBS may have more trouble absorbing nutrients from their food.
Fatigue may make you sleep-in longer, find the need to nap more, feel less focused or become depressed. You may also experience aching muscles, headache or tired eyes. There have been links made with IBS to Fibromyalgia & Chronic Fatigue Syndrome.