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Irregular, unhealthy sleep adds years to brain

May 4, 2011 12:00:00 AM PDT
Researchers have said it before: Americans do not get enough sleep. And we've all heard about the impact sleep deprivation can have on a person. But what about too much sleep?

We are learning more about what happens to your body when you don't get enough sleep. We know chronic sleep deprivation can hurt your heart health and lead to weight gain. But what does it do to your brain? A new study in the journal Sleep finds unhealthy sleep patterns can age your brain.

So how much sleep do you get?

You be getting six hours or less of sleep. Or you might be getting more than the standard eight hours. Either way, a new study suggests too little or too much sleep can affect your brain.

"Pretty much everybody on the planet knows when they don't get a good night's rest, their brain doesn't work as well," said internal medicine specialist Dr. John de Beixedon.

But new evidence shows it's more than that. In a seven-year study, people who slept fewer than six hours or more than eight had brains that acted older than their chronological age. Four to seven years older.

In the study, people who got too little sleep or too much sleep scored lower on vocabulary, reasoning and other key cognitive tests.

"People who are sort of chronically sleeping less, possibly sleep-deprived, sure enough had a worse functioning overall of their actual noggin," said de Beixedon.

While researchers aren't sure why sleeping more ages the brain, internal-medicine experts suspect people who sleep longer hours may have obstructive breathing problems such as sleep apnea. They sleep longer because they're not getting quality sleep.

Either way, de Beixedon says, the study proves sleep is just as important to overall health as diet and exercise.

"If you go to sleep earlier and you wake up earlier, you follow the natural circadian rhythm of human life, it's probably healthier for you," said de Beixedon. "It's what we were designed for."

De Beixedon adds it's not possible to catch up on your sleep on the weekends, nor can your brain make up for years of chronic sleep loss.

Also he says people who work the night shift will experience cognitive problems. But those who work changing work schedules will feel it even more.