Get Sleep or Get Dementia

If you do not get enough sleep as an adult, you are more likely to develop dementia when you are elderly. A large study of almost 8000 people followed over 25 years shows a 30% increase in risk of dementia for those who get 6 or fewer hours of sleep on average.

Getting enough sleep is important for several reasons. It leaves you more refreshed. Not getting enough sleep is the most common cause of daytime sleepiness. Daytime sleepiness increases risk of accidents. People who do not get enough sleep are more likely to gain weight. They are also more likely to develop high blood pressure.

People who got 6 or less hours of sleep at age 50 and continued to do this at age 60 and at age 70 were the most likely to get dementia. People who got more than 8 hours of sleep were also more likely to get dementia. However, the number of such people was small, so significant conclusions could not be drawn. This does suggest that there is an optimal amount of sleep (more than 6 but less than 8 hours). Getting too little sleep clearly causes many problems, including dementia and excessive sleepiness. Getting too much sleep may also cause problems, including insomnia and possibly dementia.

Why might people who get less sleep develop dementia?

During sleep, the spaces between brain cells open. Toxins accumulated during the day are removed. If we get less sleep, toxins may accumulate in the brain. Possibly, the result is an increased risk of dementia.

There was some good news for people who are not getting enough sleep. If they did not get enough sleep at age 50, but increased their sleep to about 7 hours at a later age, their risk of getting dementia was not quite as high as it was for people who continued to get less than 6 hours of sleep.

The take-away

Make sure to get about 7 hours of sleep (which will typically require about 8 hours in bed). Getting less than 6 hours of sleep is definitely a problem, and getting more than 8 hours may also be a problem. If you are unable to get at least 6 hours of sleep because you are sleeping poorly, seek help. Also, seek help if you regularly require more than 8 hours of sleep (usually because you are excessively sleepy). We can help. We are open through the Covid pandemic and take great care and precautions.