You have probably heard of this before. Some people are able to get a really good sleep at night. And we mean, an entire orchestra can perform right against their ear and they will not even bat an eyelid. And there are those unfortunate who don’t get such deep slumbers because someone who sneezed in a room against theirs would cause them to wake up startled. Although many people are self-proclaimed light sleepers or heavy sleepers, researchers have found that little is actually known about why people react differently to noises and other stimuli during sleep.Genetics, lifestyle choices, and undiagnosed sleep disorders may all play a role. In addition, some studies suggest that differences in brain wave activity during sleep may also make someone a light or heavy sleeper. But whichever category you’re in, one thing is certain: The quantity and quality of the sleep you get both play an important role in your health.
During sleep, you alternate between cycles of REM (rapid eye movement) and NREM (non–rapid eye movement) that repeat about every 90 minutes. NREM sleep consists of three stages, the first being the lightest stage, during which you’re most likely to be woken up. Stage one, or the phase between being awake and asleep, is considered light sleep. Deeper sleep begins in stage two, as your breathing and heart rate become slower and your body temperature drops.Stage three is the deepest and most restorative stage of sleep (it’s also called “slow-wave sleep”), in which breathing further slows, muscles relax, and tissue growth and repair occurs.Next is REM sleep, which is characterized by your eyes moving rapidly from side to side, as well as brain activity, heart rate, and blood pressure that actually look more similar to being awake than asleep. This is the stage of sleep when the most dreaming occurs, as well as important parts of the memory consolidation process.
In general, as people age, they spend less time in the slow-wave and REM stages of sleep and more time in the lighter stages. But it’s also important to note that how much time someone spends in light or deep sleep over the course of a night can vary significantly from person to person and night to night. Also, the amount of deep sleep someone gets isn’t necessarily correlated to the amount of total sleep they get. Someone who gets eight hours of sleep a night, for instance, may not experience as much slow-wave, deep sleep as someone else who gets just six hours a night. Previous research suggests that differences in how sleeping people respond to noise may be related to levels of brain activity called sleep spindles. The researchers found that people whose brains produced the most of these high-frequency sleep spindles were more likely to sleep through loud noises.If someone is not feeling rested and thinks it’s because they are sleeping lightly, they should look at the factors that might be contributing to their inability to achieve a deep sleep.Some sleep disorders, such as obstructive sleep apnea, may contribute to light sleep by causing awakenings throughout the night, due to breathing irregularities.But it’s worth noting that just because you feel like you’re a light sleeper or that you awaken easily during the night due to outside noise or other disturbances doesn’t mean that you’re not actually getting the sleep you need. What’s more important is that you wake up feeling rested, which is a good indication that you’re getting the deep sleep you need. In most cases, factors under your own control affect the quality of sleep you get. There are lots of issues related to lifestyle, medications, and caffeine that can lighten sleep. People might also not be getting enough sleep because they’re not spending enough time in bed due to the choices they make.
To improve the quality of your sleep, you should have a set bedtime and a set wake time. Turn off the TV and keep electronic devices away from the bedroom. This means keeping your cell phone out of the room, so a text won’t wake you up, especially if you’re a light sleeper. Also avoid screen time at least 30 minutes before bedtime. Unplugging an hour or more before your head hits the pillow is even better. Use earplugs or noise-canceling earbuds. This will help drown out ambient noise, especially if your bedroom is facing a window that picks up traffic sounds from outside. Lastly watch what you eat close to bedtime. Try to avoid snacks packed with sugar, which could cause a sugar spike. Also avoid caffeine and nicotine, both of which are stimulants. And spicy, acidic foods may cause heartburn or acid reflux that can interfere with sleep.