- With Mayo Clinic emeritus internist
Kenneth G. Berge, M.D.
read biographyclose windowBiography of
Kenneth G. Berge, M.D.
Kenneth G. Berge, M.D.
Dr. Kenneth Berge has been involved in Mayo Clinic's Web publications since they began in 1995, advising editors and the public throughout his tenure.
He develops content for the Ask a Specialist segment and helps plan and edit other content and design. Dr. Berge has also been an editor of CD-ROMs and books produced by Mayo Clinic.
Dr. Berge, board certified in internal medicine, has been with Mayo Clinic since 1955 and early on had a special research interest in cardiovascular risk factors, including cholesterol and hypertension. Dr. Berge served as a leader for a number of major National Institutes of Health clinical trials that established the fundamental roles for lifestyle modifications needed to prevent cardiovascular disease. Dr. Berge served in various capacities with the National Heart, Lung and Blood Institute. He was vice chairman of the steering committee for the Coronary Drug Project and chairman of the steering committee on Systolic Hypertension in the Elderly Program from 1984 to 1993.
He won the Teacher of the Year Hall of Fame Award in 1987 and was Mayo Clinic voting staff president in 1976. He is an emeritus professor of medicine at Mayo Clinic College of Medicine.
He became a fellow in the American College of Physicians in 1962 and was president of the Minnesota chapter of the American College of Physicians in 1981.
As a respected physician, researcher and teacher with more than 40 years of clinical experience, Dr. Berge, a native of Wahkon, Minn., brings a wealth of knowledge to the Web site. "My career as a primary care physician for more than 40 years has provided me with experience in communicating complex information to a wide variety of patients in a manner that they could understand. I also came to know their common concerns and questions," he says.
More answers
- Sun-protective clothing: Worth the expense?
- Shift work: How do I adjust to daytime sleeping?
- Passive-aggressive behavior: How can I recognize it?
- Does sunscreen expire?
- Night shift and cancer: Any connection?
- Tanning beds: Safer than the sun?
- Universal blood donor type: Is there such a thing?
- Cell phones and cancer: What's the risk?
- Choosing sunglasses: Is UV protection important?
- Healthy skin: What role does diet play?
- Whitening toothpaste: Does it actually whiten teeth?
- Dental floss vs. water pick: Which is better?
- Air fresheners: Could continuous scents hurt my lungs?
- Electric toothbrush: Better than a regular toothbrush?
- see all
Mayo Clinic Health Manager
Get free personalized health guidance for you and your family.
Get Started
Mayo Clinic Housecall
Stay up to date on the latest health information.
What you get
- Free weekly e-newsletter
- Mayo Clinic expertise
- Recipes, tools and other helpful information
- We do not share your e-mail address
Question
Sleep guidelines: How many hours of sleep are enough?
I'm always hearing about the importance of getting plenty of sleep. What does this mean exactly? How many hours of sleep are enough for good health?
Answer
from Kenneth G. Berge, M.D.
The amount of sleep you need depends on many factors, especially your age. Infants typically sleep at least 16 hours a day. Most preschoolers need at least 11 hours of sleep a night, and most school-age children need at least 10 hours of sleep a night. By the teenage years, nine hours of sleep a night is usually adequate. For most adults, seven to eight hours a night seems about right.
Although some people feel rested on as few as five hours of sleep a night, recent studies call this notion into question. Researchers have found that people who sleep so little over many nights don't perform as well on complex mental tasks as do people who get closer to seven hours of sleep a night. Additionally, researchers have found that adults who get much more or less than seven hours of sleep a night have a higher mortality rate than do adults who sleep about seven hours a night.
As you get older, your sleeping patterns may change. Older adults tend to sleep more lightly and awaken more frequently during the night than do younger adults — but there's no evidence that older adults need less sleep than do younger adults.
At any age, getting enough sleep boosts your immune system. Sleep also helps your nervous system work properly. Likewise, too little sleep can leave you drowsy and unable to concentrate. Lack of sleep also impairs memory and physical performance.
So how many hours of sleep are enough for you? It's probably best to aim for about seven to eight hours of quality sleep a night. If you feel drowsy during the day — even during boring activities — you're probably not getting enough sleep. Also, remember that quality of sleep is just as important as quantity. If your sleep is frequently interrupted or cut short, you're not getting quality sleep.
If you experience frequent daytime sleepiness, even after increasing the amount of quality sleep you get, talk to your doctor. He or she may be able to identify any underlying causes — and help you get a better night's sleep.
Next questionSun-protective clothing: Worth the expense?
- Brain basics: Understanding sleep. National Institute of Neurological Disorders and Stroke. http://www.ninds.nih.gov/disorders/brain_basics/understanding_sleep.htm. Accessed Sept. 10, 2008.
- How much sleep do we really need? National Sleep Foundation. http://www.sleepfoundation.org/site/c.huIXKjM0IxF/b.2417325/k.3EAC/How_Much_Sleep_Do_We_Really_Need.htm. Accessed Sept. 10, 2008.
- Ferrie JE, et al. A prospective study of change in sleep duration: Associations with mortality in the Whitehall II cohort. Sleep. 2007;30:1659.
- Banks S, et al. Behavioral and physiological consequences of sleep restriction. Journal of Clinical Sleep Medicine. 2007;3:519.
- Youngstedt SD, et al. Long sleep and mortality: Rationale for sleep restriction. Sleep Medicine Reviews. 2004;8:159.
