New Information to Sleep on
New Information to Sleep on
We often fail to recognize or acknowledge its importance, but sleep, like a high-nutrient diet and exercise, is a crucial component of excellent health. As our lives become increasingly busy, we are sacrificing sleep: in 1942, mean reported sleep time for adults was 7.6 hours, and by 2001, the average was down to 6.7 hours.1 According to a poll by the National Sleep Foundation, 63% of American adults report that their sleep needs are not being met, and 43% report that on weeknights they rarely or never get a good night’s sleep.2But we need adequate sleep to work optimally in our daily activities.3
Why do we need sleep? Our brains work best when we are well-rested: during sleep, our brains stabilize newly formed memories, and adequate sleep promotes learning and cognitive performance the next day.3,4 Sleep is also essential for proper immune function.5 Getting adequate sleep regularly may reduce the severity of cold symptoms and also may maintain sufficient numbers of natural killer cells.6 In fact, there is some evidence that poor sleep could impair the immune system’s ability to eliminate, small, newly established tumors before they become dangerous.7 In addition, melatonin, which is a hormone produced in response to darkness and during sleep, is an antioxidant and an inhibitor of cancer cell growth.8-10 Allowing the body to produce sufficient melatonin is essential. Inadequate sleep is associated with impaired learning ability, faster aging of the brain, impaired driving and work performance, overeating, obesity, elevated cholesterol, and increased risk of diabetes, hypertension and death from all causes. Plus, lack of sleep negatively affects our appearance and emotional state.4,11-21
Are you getting enough, good quality sleep? The precise amount of sleep required for adults has been debated, and differs between individuals. But, if you wake up to an alarm clock you are most likely sleep-deprived.6Here are some strategies to consider if you’d like to improve the quality of your sleep:6,22
Minimize electronic device use at night. Smartphones, computer screens, televisions and tablets emit blue light, which suppresses melatonin production. Using these devices close to bedtime can disrupt sleep.23 If you wake in the middle of the night, don’t turn on your TV, smartphone or computer; the light will turn off melatonin and cause you to feel more alert. Instead, relax, read under low light or meditate until you feel sleepy again.
Make your sleep environment as dark as possible. Don’t keep clocks that emit light or night lights in the bedroom; light-blocking curtains or a sleep mask can reduce exposure to outside light and enhance your sleep quality. Light exposure regulates our internal clock: bright light makes us alert in the morning, and a dark room at night promotes melatonin production and good sleep. Exposure to light soon before bed or during sleep reduces the depth and quality of sleep. Even a low level of light exposure through closed eyelids (such as a night light) can reduce melatonin production, and this disruption of our natural rhythms has ill health effects. Light exposure at night is associated with an increased risk of cancer, most strongly with breast cancer.24,25
Sleep on a consistent schedule, going to bed at the same time every night, and waking up at the same time every morning.
Don’t wake up to an alarm clock if possible; the alarm clock wakes you abruptly and use of the snooze button can rob you of valuable REM sleep. When you wake naturally, your body prepares you during the final sleep cycles by shifting hormone production—reducing melatonin and increasing cortisol, which helps you to become alert.6,26
Minimize noise. How noise affects one’s sleep is somewhat individual, based on what is familiar and typical. Earplugs or “white noise” (for example from a fan) may help to prevent noises from disrupting sleep.27
Exercise. Exercising regularly (especially vigorous exercise) promotes healthy sleep, but exercise close to bedtime is usually not recommended.
Sleep at a comfortable, but cooler temperature. Body temperature naturally drops during sleep. Sleeping in a warm room (above 75°F) or trapping in excessive heat with extra blankets may disrupt sleep.
Follow a high-nutrient diet. A low intake of vegetables is associated with poor sleep.31 Those following aNutritarian diet may get better quality sleep than people eating poorly, and therefore may require fewer hours of sleep.
For those who experience difficulty sleeping, morning light exposure (or light therapy) helps normalize melatonin cycling as a means of establishing better sleep patterns and resolving insomnia. In the mornings open the shades wide and get in a sun lit room, go outside or use a therapeutic light. Tart cherry juice, a natural dietary source of melatonin, may be an effective addition.32,33 Supplementing to achieve adequate omega-3 fatty acids and zinc may also benefit sleep.34-36 These natural methods are preferable to prescription sleep drugs, which are linked to a dramatic increase in risk of death. These findings demonstrated a three-fold increased risk of death associated with regular use and a 35 percent higher risk of cancer.37
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