The human body’s increased response to insulin during deep sleep and improved blood sugar control the next day may be why a lack of quality sleep is thought to increase diabetes risk, researchers say.
Stronger and more frequent coupling of deep sleep brain waves, especially sleep spindles and slow waves, triggered the body’s parasympathetic nervous system into action, researchers from the University of California (UC) Berkeley, USA, found after investigating sleep. data on 600 persons.
The parasympathetic branch of the nervous system is associated with calming and soothing the body by producing physiological effects such as slowing the heart and dilating blood vessels.
The researchers detected this shift in the participants by measuring changes in their heart rate.
They further found that switching to this calm and restful mode increased the body’s ability to respond to insulin, the blood sugar-regulating hormone that instructs cells to absorb glucose from the bloodstream, thereby preventing harmful blood sugar spikes.
Their findings are published in the journal Cell Reports Medicine. “These synchronized brain waves act like a finger flicking the first domino, setting off an associated chain reaction from the brain down to the heart and out to change the body’s regulation of blood sugar,” said Matthew Walker, professor of neuroscience and psychology, UC Berkeley and principal author of the study.
The combination of sleep spindles and slow waves of deep sleep is known to improve learning and memory.
However, this human study, based on a 2021 rodent study, revealed a new and previously unrecognized function of these waves in the critical bodily function of blood sugar control.
“This particular association of deep sleep brain waves predicted glucose more than sleep duration or sleep efficiency,” said Raphael Vallat, a UC Berkeley postdoctoral fellow and co-author of the study.
“This suggests that there is something uniquely special about the electrophysiological quality and coordinated ballet of these brain oscillations during deep sleep,” Vallat said.
The researchers then replicated the same effects by examining a separate group of 1,900 participants.
They said that as a modifiable lifestyle factor, sleep can be used to treat high blood sugar and type 2 diabetes.
Their study further opens up the prospect of new technologies capable of safely altering the brain waves of deep sleep to help people better manage their blood sugar, they said.
