You have probably noticed that we ask you to log your stress in the FoodMarble app each day. You might wonder why this is important, and how it’s linked to your digestion. Well, many people find their digestive symptoms get worse during periods of stress, in particular those of us with IBS. But, do we know why this is?

It’s not fully understood but let’s talk about what we do know.

Your hormones play a big part

One key player is the hormone “corticotrophin-releasing hormone” (CRH). CRH regulates the stress response in the gut and the brain. It has been well established that the interaction between the brain and the gut (the “gut-brain axis”) plays a major role in the development and onset of IBS symptoms.

So what does CRH do in the gut?

  1. It has been shown to increase gut motility, which may result in altered bowel movements (E.g. diarrhea). This is why, when placed under stress, you might have a sudden urge to use the toilet. This response happens to everyone, but it is more pronounced and long lasting in those with IBS
  2. It also has been shown to promote low grade inflammation by increasing the permeability of the intestinal wall. This results in an influx of circulating immune cells, for example mast cells. When these are activated they can release histamine. Read my blog for more information on histamine
  3. Increased permeability influences the sensitivity of the gut wall. This increases visceral hypersensitivity – the increased sensation of pain and discomfort in your gut
  4. The composition of the gut microbiota can change in response to CRH, reducing the numbers of good bacteria. This leads to gut dysbiosis
  5. It influences important gut secretions, for example mucus production. This is important to maintain a balanced gut environment
Close up of woman's hands on lap

Photo by boram kim on Unsplash

Let’s take a few steps back – so what happens when CRH is released?

A part of our brain (the hypothalamus) releases CRH in response to a stressor. CRH then travels to its receptor, where it can stimulate an array of processes. This leads to the production and release of the stress hormone cortisol.

Cortisol has been shown to cause increased absorption of water and sodium in the colon and rectum, leading to reduced water in the faeces. This is why sometimes during times of stress you can also get quite constipated. Too much CRH (or low cortisol) will result in watery diarrhea. Increased cortisol (or low CRH) will result in constipation.

For most people, cortisol levels are higher in the morning and lower at night time. In one study they were able to demonstrate that those with IBS have much higher levels of circulating cortisol in their saliva upon awakening, in comparison to their healthy counterparts. The natural cortisol pattern appears to be exaggerated in those with IBS.

So, why log my stress levels in the FoodMarble app?

By logging your stress daily, you get a better idea of what is going on. For example, if your symptoms are worse one day, it’s useful to know what your stress level was on that particular day, or the day before. You might notice that some symptoms are not related to food at all, and are linked to your stress levels (or even the quality of your sleep, which you can also log in your FoodMarble app). This means you can avoid restricting foods unnecessarily, which is important for our overall health, and especially our gut-health.

I find it’s easiest to log my stress level in the evening, so I can assess my stress over the full day. It takes less than 5 seconds to log your stress levels and can help you spot trends in your digestive symptoms more easily and quickly. You can even set up reminders on the app so you don’t forget!

Screenshot of FoodMarble AIRE app Stress and Sleep Log

Cover photo by Matthew Henry on Unsplash

FoodMarble AIRE is the world’s first personal hydrogen breath tester. It is a pocket-sized breath analysis device. It helps people with chronic digestive issues determine the foods that work best with their digestive system.

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