Nine myths about sleep.(Dream on)

Getting one hour less sleep per night than needed won't affect you.

REALITY Getting even slightly less sleep can leave you feeling less energetic, hinder your ability to think properly and respond quickly, affect cardiovascular health, and make it more difficult for your body to fight off infections, particularly if the lack of sleep continues.

Your body quickly adjusts to different sleep schedules.

REALITY Our biological clocks are programmed so we're more alert during the day and more drowsy at night. Most people can reset their internal clock by one or two hours a day, but it can take a week or longer to adjust to dramatically altered sleep/wake cycles, such as when traveling across time zones or switching from the day shift to working overnight.

You need less sleep as you age.

REALITY Older people need just as much sleep as other adults, but they often get less or find it less refreshing because they spend less time in deep, restful sleep and might be easily awakened. They also tend to suffer from aches, pains, and medical conditions that can disrupt sleep.

Extra sleep can prevent daytime fatigue.