“You’ll feel better for a good night’s sleep”, or so the saying goes. But is this just an Old Wives’ Tale or is there any truth in the idea that sleep may help in the treatment of illness, and in particular gastrointestinal disorders?
Researchers at the Eastern Virginia Medical School believe that sleep disruption can have a detrimental impact on gastrointestinal conditions and is urging doctors to take sleep disruption more seriously in their treatment of patients.
How poor sleep affects our gut
They point to the fact that not getting enough sleep can increase proinflammatory cytokines, which increase inflammation in the body, and can alter visceral and somatic perception – basically, the way the body and mind interact.
David A. Johnson, author of Sleep Effect on Gastrointestinal Health and Disease, describes a:
“dynamic bidirectional relationship between sleep and the GI system”. He explains that sleep can have an impact on our circadian rhythms, neurohormonal transmitters and gut flora.
The relationship between our brain and our gut is well understood by scientists, who recognise the dynamic, interdependent relationship between them.
Less well-documented is the link between poor sleep and our gut.
It is unclear, for example, if poor sleep worsens gastrointestinal symptoms, or if gastrointestinal conditions disrupt sleep and interrupt our natural circadian function.
The circadian rhythm is our 24-hour internal clock that governs when we feel alert and when we feel sleepy. It is controlled by the hypothalamus in our brain and influenced by outside factors, such as darkness.
For adults, the biggest dip in energy happens in the middle of the night – between 2am and 4am – and just after lunchtime, normally from around 1pm to 3pm. When you are sleep-deprived you will notice bigger swings of sleepiness and alertness.
A disruption in our natural circadian rhythms, for example jet lag, can cause us to feel out of sorts and unable to concentrate. It can also affect the organs of the body, including the gastrointestinal system.
Our gastrointestinal system has its own circadian clock – digestive function is different at night to during the day.
People can develop gastrointestinal symptoms when their circadian rhythms get disrupted. It has been found, for example, that nurses who work night shifts or rotating shifts experience higher levels of IBS and abdominal pain than those who work regular day shifts.
According to Sarah K. Ballou, a GI psychologist at Beth Israel Deconess Medical Center, poor sleep is one of the primary factors in IBS symptoms.
Sleep disturbance and IBS
In a study of 24 women with IBS published in the Journal of Clinical Sleep Medicine, those with poorer sleep reported on increase in abdominal pain, anxiety and fatigue the following day.
Studies also show that people with IBS wake up in the night with abdominal pain or because they need a poo, which shows that gastrointestinal conditions also contribute to sleep disturbance.
Stress, anxiety and depression in people with IBS leads to an increase in symptoms and greater sleep disruption. Some of the pain relief given to IBS sufferers can also disrupt sleep.
Intestinal dysbiosis and leaky gut
Disruption to sleep and circadian rhythms may also be linked to intestinal dysbiosis (bacterial or fungal overgrowth in the small intestine), which causes inflammation. Our gut microbiome fluctuates throughout the day and night, depending on food intake, exercise and excretion.
It starts and ends in the same place but if sleep is disrupted, the natural microbiome fluctuation is impacted and inflammation persists even after normal sleep is restored.
Researchers found that disrupted sleep appears to induce permeability of the intestinal membrane – so-called leaky gut – in mice. If the gut becomes permeable, harmful microbes can leak into other parts of the body. This disruption may result in altered brain chemistry which can lead to further sleep disruption.
What can be done to help
Researchers found that melatonin can be effective in managing gastrointestinal symptoms that are worsened by a disruption to the circadian rhythms.
Melatonin not only helps to regulate the circadian rhythm but it also helps to support the gastrointestinal tract. Studies in mice showed that melatonin blocked drug-induced colitis in mice, for example.
When it comes to disrupted sleep, cognitive behavioural therapy (CBT) was found to be particularly effective. Between four and six sessions help patients to make behavioural changes to enable them to sleep better. These might include strategies for handling the thoughts that can keep them awake if something wakes them up in the middle of the night.
Developing healthy practices around sleep, such as not watching TV in bed and avoiding caffeine after noon, also proved to be helpful.