Getting enough quality sleep is essential to good health. As I’ve noted in a previous IFOD, there are four primary things to focus on for health and wellness and sleep is the most important thing, followed by good nutrition, then resistance training, and lastly cardio.

A new study out of Washington University in St. Louis provides more backing for the importance of sleep. In the study, researchers tracked the sleep and cognitive function of older adults for several years and found that hitting a sleep “sweet spot” is associated with brain health.

According to the study’s lead author,” there is a middle range, or ‘sweet spot,’ for total sleep time where cognitive performance was stable over time. Short and long sleep times were associated with worse cognitive performance, perhaps due to insufficient sleep or poor sleep quality.” The paper found that the optimum range of sleep was 5.5 — 7.5 hours of sleep with more or less than that being associated with cognitive decline. The researchers also noted that their findings indicate that it’s not just duration of sleep that matters — the quality of sleep is important as well, which means cycling through the four stages of sleep 4-6 times per night with the proper amount of REM and deep sleep.

Why might sleep be so important for maintaining our mental faculties? A prior study at Wash U of mice found that “sleep deprivation increases levels of the key Alzheimer’s protein tau. And, . . . that sleeplessness accelerates the spread through the brain of toxic clumps of tau ­– a harbinger of brain damage and decisive step along the path to dementia.” And a study out of Stanford discovered that not getting enough sleep was associated with higher amounts of Amyloid-β in the brain which is associated with Alzheimer’s.

So, what can you do to improve your sleep quality? Here’s an IFOD on that topic: Top Tips for a Better Night’s Sleep