The Relationship between Sleep and Digestion: It's Complicated.

You know that I’m a registered dietitian, so why am I talking about sleep?


First, 1 in 4 or more Canadian adults do not get enough sleep and 1 in 5 or more Canadian adults don’t get good quality sleep. So we know it’s a problem. Second, sleep can profoundly affect our digestive health and digestive health and gastrointestinal (GI) conditions are my bread and butter (yum).


Sleep deprivation means not sleeping long enough, waking up frequently during the night, or not getting the right balance of sleep (REM vs NREM sleep). Also, sleep deprivation is different from insomnia. Although side effects of both deprivation and insomnia can be similar, insomnia is a sleep disorder while deprivation is not. Sleep deprivation is referring to poor quality sleep either in the short- or long-term.


So now that we get what sleep deprivation is let’s look at some causes and symptoms:


Causes:

  • Poor sleep hygiene

  • Sleep disorders

  • Mental illness

  • Shift work

  • Life in general (let’s be honest)


Symptoms:

  • Difficulty concentrating

  • Poor cognition

  • Mood swings (we’ve all been there)

  • Feeling exhausted during the day

  • Poor memory

  • Short attention span


These lists are not exhaustive and what may cause sleep deprivation and the symptoms experienced are going to be different for different people because that’s just how genetics work. There are a lot of negative health effects linked to sleep deprivation but we are going to focus on what the research says about how it can affect, or be affected by, gastrointestinal (GI) health.

But first, what is sleep hygiene?


You may not be familiar with this term, but I feel like I’ve been hearing it everywhere over the last couple years. Sleep hygiene is setting up a sort of routine both at night and during the day to maintain adequate duration and quality of sleep. One of the main points of sleep hygiene is going to bed and getting up at the same time EVERYDAY. Which, personally, I feel is tricky and maybe not realistic.


For tips on sleep hygiene click here.

Sleep and digestion have a complicated relationship. Sleep deprivation can be both a risk factor for and a side effect of GI conditions. Functional GI disorders, like IBS, are possibly caused in part by sleep deprivation. Much like how higher rates of functional GI disorders are found in populations of people who have gone through traumatic events or work and live in stressful environments, the same seems to be true of sleep deprivation.


Several studies I looked at concluded sleep deprivation to be a risk factor for IBS and other functional GI disorders. One study found that 50% of people (in the USA) who were diagnosed with IBS also reported sleep deprivation, but other studies suggest higher rates. There are many studies out there that report people who work shift work, like nurses and physicians, have higher rates of IBS compared to the general public. This could be a case of sleep deprivation leading to IBS, IBS leading to sleep deprivation, or something else is causing both IBS and sleep deprivation. It’s possible that all three of these options are the case, it just depends on the person.


Once we have sleep deprivation and a GI condition established, studies also show that sleep deprivation can make the condition worse. In IBS, other functional GI disorders, and in GERD symptoms are worsened through hyperalgesia or increased sensitivity to pain. When someone is sleep deprived, for any reason, they perceive their GI symptoms as worse because of hyperalgesia. This phenomenon is not limited to GI conditions, anyone who has a chronic pain condition will also be familiar with it’s effects.


Sleep deprivation can also cause those with inflammatory bowel disease (IBD; crohn’s or ulcerative colitis) to relapse into active disease. Studies have shown that it’s almost twice as likely for someone diagnosed with IBD to relapse when they have reported chronic sleep deprivation within the last 6 months. Lastly, one study suggested that people with sleep apnea are at an elevated risk for peptic ulcer disease (PUD) or, if they already have PUD, for bleeding to occur.


All of this is why when I have my initial appointment with a client we talk about sleep because it may be an important factor in our treatment plan. It’s also important to remember that sleep deprivation is linked to more health problems than just GI conditions.


Take-aways:


  1. Sleep deprivation may be a risk factor for IBS or other functional GI disorders.

  2. Sleep deprivation can worsen the symptoms or the disease state of GI conditions.

  3. There may be a third culprit that is causing or perpetuating both GI conditions, like IBS, and sleep deprivation. My guess is stress.

  4. Sleep is IMPORTANT.


P.S.


A lot of the studies I read concerning IBS had marital status as a risk factor, just saying.


Sources:


Ali, T. (2013). Sleep, immunity and inflammation in gastrointestinal disorders. World Journal of Gastroenterology, 19(48), 9231. https://doi.org/10.3748/wjg.v19.i48.9231

Canada, P. H. A. of. (2019, September 6). Government of Canada. Are Canadian adults getting enough sleep? Infographic - Canada.ca. https://www.canada.ca/en/public-health/services/publications/healthy-living/canadian-adults-getting-enough-sleep-infographic.html.

Cremonini, F., Camilleri, M., Zinsmeister, A. R., Herrick, L. M., Beebe, T., & Talley, N. J. (2009). Sleep disturbances are linked to both upper and lower gastrointestinal symptoms in the general population. Neurogastroenterology & Motility, 21(2), 128–135. https://doi.org/10.1111/j.1365-2982.2008.01181.x

Lim, S.-K., Yoo, S. J., Koo, D. L., Park, C. A., Ryu, H. J., Jung, Y. J., Jeong, J. B., Kim, B. G., Lee, K. L., & Koh, S.-J. (2017). Stress and sleep quality in doctors working on-call shifts are associated with functional gastrointestinal disorders. World Journal of Gastroenterology, 23(18), 3330. https://doi.org/10.3748/wjg.v23.i18.3330

Maneerattanaporn, M., & Chey, W. D. (2009). Sleep disorders and gastrointestinal symptoms: chicken, egg or vicious cycle? Neurogastroenterology & Motility, 21(2), 97–99. https://doi.org/10.1111/j.1365-2982.2008.01254.x

Patel, A., Hasak, S., Cassell, B., Ciorba, M. A., Vivio, E. E., Kumar, M., Gyawali, C. P., & Sayuk, G. S. (2016). Effects of disturbed sleep on gastrointestinal and somatic pain symptoms in irritable bowel syndrome. Alimentary Pharmacology & Therapeutics, 44(3), 246–258. https://doi.org/10.1111/apt.13677

Sleep Deprivation: Causes, Symptoms, & Treatment. Sleep Foundation. (2020, November 4). https://www.sleepfoundation.org/sleep-deprivation.

What Is Sleep Hygiene? Sleep Foundation. (2020, August 14). https://www.sleepfoundation.org/sleep-hygiene.