Can deep sleep help stop dementia?

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**Amber Minogue** (1:04)
Can deep sleep help stop dementia?
Thanks for asking. It's not news that if you don't get a good night's sleep, you'll probably not be your best the next day. But while you're snoozing, particularly in deep sleep, your brain is not just powered down. It's busy cleaning out the day's toxins, almost like it's washing your brain and getting it ready for the next day. Sleep is not just a state where things turn off. Sleep is a very active state for the brain, and it seems to be a special state for fluid flow within the brain. This is Laura Lewis, Assistant Professor of Biomedical Engineering at Boston University for The Guardian newspaper. What happens if we don't get enough deep sleep? Not getting enough deep sleep can have a number of detrimental effects. Toxic byproducts can build up and actually increase our risk of dementia and brain disease. Professor Maiken Nendegard at the University of Rochester Medical Center in the US and her colleagues have discovered through their brain imaging research on human volunteers that while they slept, their brains were cleaned. This was most notable during the deepest phase of non-rapid eye movement sleep, which happens usually during the early morning hours. We saw these large waves of fluid flow that started to wash over the brain about every 20 seconds or so and could travel quite long distances inside the brain, she says. As soon as people woke up, this flow pattern would disappear. This system whereby the brain cleans itself during deep sleep is due to a series of channels which surround the brain's blood vessels and that allow cerebral spinal fluid, a fluid that usually surrounds your brain, to be pushed through the brain tissue by the pulse of blood. This then carries away any molecular waste. This system is crucial as your neurons are extremely active during the day and produce waste that needs to be removed. Just as if you don't have a filter in an aquarium, the fish will die in their own dirt. All this stuff accumulates in the brain that needs to be removed. Nedda Gardin says.
Sadly as we get older, it's harder to get enough deep sleep, which is vital not just for cleaning our brains but also for memory, regulating blood glucose and the release of hormones that help repair muscle, bone and immune cells. How can we boost our deep sleep? When it comes to sleep, quality is important.
Avoid drinking coffee or alcohol just before bed. Likewise, try not to use electronic devices and keep your room dark. If light is coming in through the window or from pilot lights on electrical devices, even if it doesn't wake you up, it may kick you into a lighter sleep stage and you won't feel as well rested, says Professor Lewis.
There you have it.
Now you know if deep sleep can stop dementia. In under three minutes, we answer your questions and help you understand the true meaning behind the trends, concepts and acronyms that are making headlines. Listen along and you really will know for sure.

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