Dramatic advances in the study of sleep in recent years have revealed that sleep "is the single most effective thing we can do to reset our brain and body health each day." Our culture consistently underappreciates the value of sleep, and our neglect of it has broad and sweeping consequences for our individual and collective wellbeing.
Thousands of scientific reports point to the following benefits of a good night's sleep: "It makes you live longer. It enhances your memory and makes you more creative. It makes you look more attractive. It keeps you slim and lowers food cravings. It protects you from cancer and dementia. It helps ward off colds and the flu. It lowers your risk of heart attacks, stroke, and diabetes. It helps you feel happier, less depressed, and less anxious." This may sound like an advertisement for a miracle drug that's too good to be true, but these are proven benefits of sufficient, good-quality sleep. Sleep is also critical for learning and for maintaining a more even keel emotionally.
-- Routinely sleeping less than 6 or 7 hours each night demolishes your immune system. Getting more than 7 hours of sleep per night has been shown to reduce the likelihood of catching common viral infections and also to boost a person's immune response in reaction to a standard flu vaccine.
-- Not getting sufficient sleep also affects your appetite. It increases the levels of a hormone that makes you feel hungry while decreasing the levels of a hormone that signals food satisfaction. This means that, despite being full, you still want to eat more.
How Much Sleep Is Enough?
The World Health Organization and the National Sleep Foundation recommend an average of eight hours of sleep per night for adults. This requires at least eight or nine hours in bed to have adequate sleep opportunity time. (For adolescents, changes in their circadian rhythms and brain development point to the importance of allowing sufficient sleep in the morning--hours after an adult typically needs to awaken.)
Tips for checking whether you are getting enough sleep:
1. After waking up in the morning, could you fall back asleep at 10 or 11 am? If yes, you are probably not getting sufficient sleep quantity or quality.
2. Can you function optimally without caffeine before noon? If no, then you are likely self-medicating your state of chronic sleep deprivation.
3. If you didn't set an alarm clock, would you sleep past that time? If so, you need more sleep.
4. Do you find yourself reading and then re-reading the same sentence on your computer screen? This is frequently a sign of an underslept brain.
Taking Steps to Improve Your Sleep
The first step for improving your sleep should be behavioral changes that are risk-free. Sleeping medications do not address the underlying sleep issues and can be harmful. A separate module on Tips for Improving Sleep discusses these behavioral changes. The National Institutes of Health offer 12 tips for healthy sleep on their website, and they advise that if there is only one piece of advice that you remember, it should be to set an alarm for when it's time to go to sleep, so that you can establish a consistent sleep schedule, with the same bedtime and wake time every day, even on the weekends.
-- Evidence suggests that reducing processed carbohydrate intake and increasing your intake of healthy fibrous foods, such as vegetables and fruits, can contribute to a deeper sleep and fewer nighttime awakenings.
-- For older adults, it is often particularly important to avoid naps after 3 pm, and to try to get exposure to sunlight late in the day, to help prevent the "early bird" drowsiness that can lead to an evening nap that disrupts efforts to get a good night's rest.
Adapted from Why We Sleep, by Matthew Walker, PhD.