Most people don’t get enough sleep. According to a recent survey, 42% of adult Americans get less than 7 hours of sleep a night, while 6% get more than 9 hours a night. This means that just 52% of adults fall within the recommended number of hours of sleep a night.
There is a small portion of the population that has a genetic mutation that allows them to need only 6 hours of sleep a night. Barring that, the number of hours of sleep you need depends primarily on age. Here are the ranges that a panel of scientists found after reviewing more than 300 studies:
As you can see, the average adult needs between 7 and 9 hours of sleep a night.
Getting too much or too little sleep has been associated with an increased risk of mortality, cardiovascular disease, type 2 diabetes, hypertension, respiratory disorders, and obesity. Getting too little sleep has also been shown to cause a steady decline cognitive function. A new poll by Gallup also found that happiness levels closely tracked the 7 to 9 hours of sleep recommendation:
So, here are 12 science-backed tips that will help you sleep better:
1. Only Use Your Bed For Sleep
Many people watch television, read books and/ or spend a lot of time thinking in bed. However, these activities can cause the bed to be associated with arousal instead of sleep. The “gold standard” treatment for insomnia is to train patients to only use their bed for sleep. Here are the steps you can take:
- Go to sleep when you’re sleepy (your eye lids are starting to drop, etc.).
- Do not use your bed for anything but sleep.
- If you feel angry, frustrated or miserable, get up and do something else (other researchers recommend getting up after about 15 minute have elapsed and you’re still awake).
- Go back to bed when you’re tired.
- Repeat steps 3 and 4 until you’re asleep.
Your circadian rhythm, or body clock, is an internal system that regulates your energy levels over a 24 hour period. Your circadian rhythm also controls hormonal levels, body temperature, metabolism and your immune system. When you sleep at erratic times, your body’s functions become misaligned with the needs of the day.
The best way to get on a consistent schedule is to wake up on at the same time every morning (including weekends). This may require using an alarm at first, but it helps keep your circadian rhythm working smoothly.
3. Develop a pre-sleep routine:
Developing a consistent pre-sleep routine helps you wind down and sends an early signal to your body that it’s time to go to sleep. So, set aside 15 minutes or more to relax, read, take a hot shower, resolve anything that might worry you, or do any other non-stimulating activity.
Being exposed to light first thing in the morning also helps keep your internal clock on pace. One study monitored participants with insomnia, then exposed them to light in the morning for a week and tracked their sleep for 3 additional weeks. Half the participants were exposed to a bright light (2500 lux) while the other half was exposed to a dim light control (100 lux). The bright light group fell asleep faster and slept for 51 more minutes on average. The bright light group also reported less insomnia, less sleep related anxiety, less daytime fatigue and improved daytime functioning. So go outside first thing in the morning. Otherwise, open the blinds and turn on the lights in the house if you can’t make it out.
On the other side of the spectrum, you should avoid light exposure as much as possible at night. One study had participants either read a book for 4 hours before bed or read from an iPad. The researchers found that reading from an iPad “prolongs the time it takes to fall asleep, delays the circadian clock, suppresses levels of the sleep-promoting hormone melatonin, reduces the amount and delays the timing of REM sleep, and reduces alertness the following morning.” So, try your best to limit your exposure to bright, blue light 2-3 hours before going to bed.
As most of you know, caffeine can keep you up at night. One study had participants take a 400 mg caffeine pill (about the equivalent of 32 ounces of coffee) either at bedtime, 3 hours before bedtime or 6 hours before bedtime. The researchers found that caffeine reduced sleep time when taken at bedtime, 3 hours and even 6 hours before sleep. Caffeine actually reduced total sleep time by an average of 41 minutes when taken 6 hours before bedtime. Taking caffeine 6 hours before bedtime also more than doubled the amount of time it took to fall asleep, increased wake time during sleep by 8 minutes, and reduced stage 1, stage 2 and slow wave sleep. Another study found that taking 200 mg of caffeine first thing in the morning (at 7:10 am) also impacted sleep later that night (although slightly). So if you’re having trouble sleeping, you might want to consider giving up caffeine altogether. If not, the earlier you drink caffeine the less it will impact your sleep. Don’t forget that caffeine isn’t just in coffee. Other common sources of caffeine include soda, tea, chocolate and energy drinks.
While alcohol can help you fall asleep, a review found that it can significantly disturb the quality of your sleep and cause you to wake up more frequently during the night. Most alarmingly, it reduces total REM sleep and increases the time it takes to fall into REM sleep. Lack of REM sleep can impact concentration, motor skills, and memory. It takes roughly an hour for your body to remove a drink from your system (depending on your weight). So if you have two drinks, stop at least 2 hours before hitting the sack (but not drinking at all is better).
8. Limit/ Avoid Nicotine:
Add sleep to the list of reasons you shouldn’t smoke. One study found that wearing a 16 mg nicotine patch reduced sleep time, sleep efficiency, subjective sleep quality and increased wakefulness throughout the night. The negative consequences were especially strong when wearing the patch at night. So, avoid smoking (and other forms of nicotine) before going to bed.
9. Use White Noise:
One review found that sound levels as low as 33 dB can cause physiological arousal (increased heart rate, etc.) during sleep. However, another study found that it isn’t the dB level that causes arousal at night, but the difference in peak dB from the baseline noise level. The study exposed participants to either noise from an ICU or noise from an ICU + white noise. They found that arousal was only increased in the noise from the ICU condition. So, if you live downtown in a city or are otherwise exposed to noise at night, a fan, white noise or earplugs are probably the way to go.
Another study found that patients suffering from insomnia slept 1.25 hours more a night, fell asleep faster, experienced higher quality sleep, and had less depression symptoms, less sleepiness and more vitality during the day after 4 months of exercise. When it comes to timing, the meta analysis found that participants went to sleep faster and woke less in the middle of the night if exercise was done 4 to 8 hours before bedtime.
Your body temperature naturally declines right before you fall asleep. Turning down the thermostat can actually facilitate the process and induce sleep. Studies show that the ideal temperature for sleep is between 61 °F and 66 °F (given that you’re wearing clothes and have at least one sheet). Interestingly, having a lower core body temperature has also been found to facilitate deep sleep. Some research even supports that insomnia occurs partly due to having an elevated core body temperature at night.
12. Don’t Watch the Clock:
A final study found that insomniacs focused more on worries, things that had happened that day, noises in the environment and about the fact that they couldn’t sleep than good sleepers. Good sleepers, interestingly, thought most about “nothing in particular.”
Sleep is one of the more overlooked aspects of a healthy lifestyle. Aim for between 7 and 9 hours of sleep a night. If you aren’t sleeping well, work on the 12 tips above and you’ll be sleeping great before you know it.
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