Ask the Expert

Q: Everybody needs different amounts of sleep. How can I tell if I am getting enough sleep for my body?

A: First, take some time to evaluate how long it takes you to fall asleep. Do you usually fall asleep as soon as your head hits the pillow? If so, it's a sign that you're not getting enough. It should take about five minutes to enter sweet slumber

Then, look at your energy level throughout the day. If you have difficulty staying awake, then you are probably not getting enough sleep. This situation can have potentially dangerous consequences. The problem starts out small -- for example, falling asleep in front of the television. But sleep deprivation can eventually build up to falling asleep behind the wheel.

Another sign, surprisingly enough, is weight gain. This is because sleep deprivation causes fat metabolism in the body to work less effectively.

While you are right that people do need different amounts of sleep, a general rule of thumb is to aim for at least eight consecutive hours every night.

Kathryn A. Lee, RN, PhD, professor in the school of nursing at the University of California and co-author of The Woman's Book of Sleep: A Complete Resource Guide.