There is good news for those suffering from stress-related sleep issues. Prebiotics – dietary fibres found naturally in foods like artichokes, raw garlic and onions – may help improve sleep and buffer the physiological impacts of stress, a first-of-its-kind study suggests.
Prebiotics are the lesser-known gut-health promoters which serve as food for good bacteria inside the gut.
“We found that dietary prebiotics can improve non-REM sleep, as well as REM sleep after a stressful event,” said Robert Thompson, a PhD researcher at University of Colorado Boulder in the US.
Prebiotics are dietary fibres found naturally in foods like artichokes, raw garlic, leeks and onions.
When beneficial bacteria digest prebiotic fibre, they not only multiply, improving overall gut health, but they also release metabolic byproducts.
Researchers fed three-week-old male rats a diet of either standard chow or chow that included prebiotics. They then monitored the rats’ body temperature, gut bacteria and sleep-wake cycles using electroencephalogram (EEG), or brain activity testing over time.
Findings revealed that the rats on the prebiotic diet spent more time in non-rapid-eye-movement (NREM) sleep, which is restful and restorative, than those on the non-prebiotic diet.
“Given that sufficient NREM sleep and proper nutrition can impact brain development and function and that sleep problems are common in early life, it is possible that a diet rich in prebiotics started in early life could help improve sleep, support the gut microbiota and promote optimal brain/psychological health,” the researchers said.
After being exposed to a stressor, the rats on the prebiotic diet also spent more time in rapid-eye-movement (REM) sleep.
REM sleep is believed to be critical for promoting recovery from stress, with research showing that those who get more REM sleep post-trauma are less likely to suffer from post-traumatic stress disorder.
Stress has previously been shown to reduce healthy diversity of gut bacteria leading to a temporary flattening of natural fluctuations in body temperature.
However, rats on the prebiotic diet were buffered from these impacts, maintaining a healthy and diverse gut microbiota and normal temperature fluctuations even after stress exposure.
“It’s far too early to recommend prebiotic supplements as a sleep aid. More studies are in the works to examine what role prebiotics can play in promoting sleep, or buffering stress in people,” Fleshner added.
The study was published in the journal Frontiers in Behavioral Neuroscience.