An intriguing new study published in the Journal of Neuroscience this year revealed chronic sleep deprivation can make the brain ‘eat itself’.

Brain neuroglia ramp up auto-digestive capabilities when deprived of sleep

Human’s brain is home to various neuroglia (cells supporting brain neurons) that function to clear cellular debris and toxic by-products of metabolism. Two of these cells are astrocytes and microglia.

In order to find out the effects different levels of sleep deprivation have on the brain, researchers from the University of Wisconsin–Madison and Geisel School of Medicine at Dartmouth carried their study on mice brains. When the mice were sleep deprived for five days in a row, the team observed that both the astrocytes and microglia have become more active.

"We show for the first time that portions of synapses are literally eaten by astrocytes because of sleep loss," said Michele Bellesi, one of the researchers of the study.

These findings are significant as a prolonged activation of microglia and astrocytes have been shown to predispose the brain to developing neurodegenerative diseases such as Alzheimer’s disease and Parkinson’s disease.

Insomnia and poor mental health behind the sleep deprivation

Insomnia is an annoying issue that many may encounter. A study in 2010 discovered that a whopping 2.2 million adults in Hong Kong have been found to have trouble falling asleep, a three-time increase from a previous study conducted in 2002. Frequent use of alcohol and poor mental health are amongst the major reasons contributing to the growth.

Apart from insomnia, a growing obsession with the internet is also leading to an increasing lack of sleep in the city. The Healthy Living Index survey conducted in 2016 showed that Hongkongers were found to spend only 6.5 hours sleeping but spending nearly four hours for non-work related internet usage. Consequently, Hong Kong fell to the bottom of the rank amongst 15 countries in the Asia Pacific, comparing to taking the 13th place in a similar study conducted in 2013.

“The more time people spend on the internet, the less time they can spend on other things,” said Thomas Isaac, Director of Intuit Research, the organisation that conducted the survey. “Sleep and exercise time are things that gets affected,” he added.

Chronic sleep deprivation has a profound impact on health

Several studies have revealed that sleep deprivation is associated with increased risks to diseases such as hypertension, heart disease, diabetes and obesity. Even immune function has also been found to be impaired with a lack of deep sleep. Mental health is also affected by the quality of sleep. In one study, participants who slept only four and a half hours a night were found to be more likely to be sad, angry, stressed and mentally exhausted.

Additionally, poor sleep has the potential to wreak havoc in all aspects of life. Besides adults, 19% of Hong Kong adolescents were found to have trouble sleeping. Poor sleep in students has been linked to poorer academic outcomes and impaired psychosocial functioning. MIMS

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