How stress affects the gut.
Can stress cause digestive issues?
The answer is most definitely yes. That’s because we have a mechanism in our bodies called the Gut-Brain Axis. It is made up of the Enteric nervous system, the Vagus nerve and the Microbiome, trillions of organisms that live in our large intestine.
When we are under prolonged and chronic stress, our stomachs become slow at emptying into the intestine. The reason for this is a primal one. When the fight or flight mechanism is activated, digestion and gut function simply aren’t important.
To illustrate this, imagine our ancestors on a hunt for food to feed their family or village. Suddenly, a lion appears that is interested in their catch. The hunters are now in danger of becoming the hunted. Their heartbeat increases and their breathing becomes rapid. This is so that oxygen-rich blood can be pumped into the muscles and brain. Glucose is released from the liver to provide energy to the muscles and brain. Now the hunters have the energy and oxygen to make quick decisions and either run fast or stand and fight.
At this point, bodily functions such as digestion become unnecessary and are shut down. Our nervous system doesn’t differentiate between lions and work stress, the outcome is the same. As a result, gastric emptying slows down.
Slow gastric emptying can lead to conditions like indigestion, gastroesophageal reflux disease (GERD) or gastritis. Symptoms may include acid reflux, burping, coughing, chest pain, nausea, bloating, constipation and/or diarrhoea.
When these symptoms occur people often turn to antacids or proton pump inhibitors (PPI’s) which are available from the local pharmacy. Whilst these products do provide immediate relief, they do not treat the root cause. Warnings are provided on the packaging and on the manufacturer’s websites that these medications should be taken for no more than two weeks. And yet I see clients who have been taking these things for years.
The result of taking antacids and PPI’s is that they diminish the quality and pH of your stomach acid. The pH scale goes from 0-14 where 7 is neutral like water. Optimal stomach acid should be 2-3 on the pH scale. However, it diminishes as we age, when we take acid suppression medications, when we have a vegan diet and when we consume primarily a junk diet.
Poor quality stomach acid leads to the poor breakdown of proteins which results in poor iron absorption. Similarly, it results in vitamin B12 deficiency as B12 relies on a substance called intrinsic factor which is secreted from parietal cells on the stomach wall. Intrinsic factor requires good quality stomach acid.
Stress can also alter the secretions within your digestive tract. As well as altering stomach acid, it can alter pancreatic enzyme secretion and alter hormone secretions such as Zonulin. Zonulin is a marker of intestinal permeability, also known as leaky gut. People with leaky gut have higher levels of Zonulin than healthy people.
Stress also increases the motility of the digestive tract. Although digestion in the stomach is slowed, when the digested food reaches the intestines, it can move through rapidly. The average time for food to pass through the digestive tract of a healthy person varies between 30-40 hours. In a stressed person it can be between 6-8 hours. This results in loose bowels, or diarrhoea and will mean that nutrient absorption will be compromised. Even if someone in this situation eats well and frequently, they will not absorb all the nutrients they need and will effectively become malnourished.
When we get a leaky gut, the tight junctions of the enterocytes that line the intestines become weak and start to separate. This allows poorly digested food particles to pass between the enterocytes, instead of being absorbed through them. This inflammation can then become systemic, affecting other mucosal membranes including the blood-brain barrier. So, a leaky gut can lead to a leaky brain and result in mood disorders and neurodegenerative conditions. Leaky gut can also lead to numerous autoimmune conditions.
Not surprisingly, stress also leads to poor food choices. When we are stressed, we lose interest in cooking or eating healthy. Food can be seen as a reward for getting through a bad situation or a bad day. Quick, convenient, tasty foods become the daily diet. Junk foods, sugary foods and drinks, coffee and alcohol are foods of the stressed and depressed. This affects our neurotransmitter synthesis as our microbiome depends upon fibre to create short-chained fatty acids and neurotransmitters like serotonin – the feel-good hormone. Depressed people have low levels of serotonin.
Junk food and sugar encourages the growth of bad bugs and candida in the large intestine. Junk food alters the quality of our stomach acid and thus the cycle continues in a spiral of despair. In time this spiral can lead to weight gain, type 2 diabetes and fatty liver disease.
If you would like my help to overcome your gut or mood concerns, book an appointment today.
Until then, good health.