Sleep does not clear toxins from the brain

By Xantha Leatham Deputy Science Editor for the Daily Mail

11:41 13 May 2024, updated 11:53 13 May 2024

Lying in bed at the end of a long day is always very relaxing.

But according to new research, the exact reason why humans need sleep is still a mystery.

It has long been believed that the brain uses sleep to flush out toxins and get rid of harmful molecules.

However now a new study suggests the opposite may be true – and experts say staying active may be more beneficial for ‘cleansing’ the brain.

A team from the UK Dementia Research Institute at Imperial College London used a fluorescent dye to study the brains of mice, tracking how quickly the dye moved from one area of ​​the brain to another before it was eventually cleared. Has gone.

The exact reason why humans need sleep is still a mystery, according to new research (stock image)

They found that fluid clearance and movement were markedly reduced during sleep and under anesthetic.

Analysis showed that clearance of the dye was reduced by approximately 30 percent in sleeping rats and by 50 percent in anesthetized rats compared to rats that remained awake.

Although the findings still need to be confirmed in humans, it casts doubt on the long-held belief that sleep clears toxins through the glymphatic system, a mechanism that flushes waste out of the brain. .

Previous research has suggested that sleep is important for preventing dementia because toxic proteins are cleared from the brain during this time.

Study co-lead author Nick Franks, professor of biophysics and anesthetics at Imperial College London, said: ‘There has been so much focus in this area on the clearance idea that it is one of the major reasons we fall asleep, and we certainly ‘We were very surprised to see this contrast in our results.’

Click here to resize this module

The researchers also said that the size of the molecules may affect how fast some toxins move through the brain, and that some compounds are cleared through different systems.

‘So far, we don’t know what it is about these conditions that slows down the removal of molecules from the brain,’ said Professor Franks.

‘The next step in our research will be to try to understand why this happens.’

Study co-leader, UKDRI’s Interim Center Director, Professor Bill Wisden, said: ‘There are many theories about why we sleep, and although we have shown that clearing toxins may not be a significant reason, But it cannot be denied that sleep is… important.

‘Sleep disruption is a common symptom experienced by people with dementia – however, we still do not know whether it is a result of disease progression or a causative factor.

‘It may well be that getting good sleep helps reduce the risk of dementia for reasons other than clearing toxins.

‘The flip side of our study is that we have shown that brain draining is highly efficient during the waking state.

‘In general, staying awake, active, and exercising can clear toxins from the brain more efficiently.’

The findings were published in the journal Nature Neuroscience.


Disclaimer : The content in this article is for educational and informational purposes only.

Leave a Reply

Your email address will not be published. Required fields are marked *