The Immune-Boosting Benefits of Sleep
Taking vitamin C isn't the only way to boost your immune system. Getting a good night's sleep will also go a long way toward defending against illness. That's especially important right now. Not only are we still in the middle of flu season, but more and more people are becoming infected with the novel coronavirus.
Here, learn about the connection between sleep and your immune system and what you can do to stay healthy all year long.
How sleep affects your immune system
"During sleep, your immune system releases proteins called cytokines," explains Stephanie Gray, doctor of nursing practice, founder of Integrative Health and Hormone Clinic in Hiawatha, Iowa. Cytokines protect against infection, inflammation, and stress.
Your body also produces infection-fighting antibodies while you sleep, as well as hormones that protect you from infectious diseases and strengthen your immune system, Gray says. A recent study, published in the Journal of Experimental Medicine, even finds that quality sleep may boost the effectiveness of specialized immune cells, called T cells.
So what happens when you skimp on snoozing? "Sleep deprivation reduces the production of those protective cytokines and infection-fighting antibodies," says Gray. According to the National Sleep Foundation (NSF), chronic sleep loss can even make the flu vaccine less effective. "Recovery time is also affected by sleep deprivation," Gray adds. "If you're lacking sleep, it's going to take you longer to recover from illness."
How to improve your sleep and strengthen your immune system
Here are some easy steps you can take in your nighttime routine to get a better night's sleep—and support your immune system in the bargain.
- Practice yoga or meditation. With the constant barrage of coronavirus news, it's hard not to feel stressed 24/7. While it's easier said than done, curbing that stress will make it easier to catch Z's. "Limiting anything that's going to spike your cortisol at night is really important," says Gray. "You want cortisol to be the lowest at night so you can get a good night's sleep." She recommends practicing yoga or meditation, or listening to calming music, to relax your mind and body before bed. One study, published in the International Journal of Medicine, shows a regular hatha yoga practice reduces stress, anxiety, and depression; another study, published in Sleep, finds that meditation eases insomnia.
- Limit exposure to blue light. You might be tempted to scroll through Twitter until 2 a.m. to stay up-to-date on the news, but the blue light emitted from your phone can do a serious number on your ability to sleep, according to research published in Chronobiology International. That's because blue light throws off your biological clock and suppresses the production of melatonin, the hormone that helps you drift off. Gray suggests stashing your phone away from your bed—ideally in another room so you're not tempted to pick it up.
- Keep your bedroom cool. "Temperature is important," says Gray. "You don't want your bedroom to be too warm." According to the NSF, the ideal bedroom temperature is between 60 and 67 degrees Fahrenheit. As your energy goes down in the evening and you become ready for sleep, your body temp goes down along with it—and when you sleep, your body's internal temp drops to its lowest level. While you snooze, your brain takes a break from regulating body temperature, meaning a room that's too hot or too cold could interrupt your slumber.
- Up your intake of magnesium. "Magnesium is the most soothing, calming mineral," says Gray. "It's great for sleep, it's great for anxiety, and it's great for stress." Magnesium helps maintain healthy levels of GABA (gamma-aminobutyric acid), a neurotransmitter that promotes relaxation. You can find magnesium in foods like nuts and seeds (almonds, cashews, sunflower seeds, pumpkin seeds), bananas, avocados, spinach, broccoli, peas, beets, beans, and soybeans. It's also available in supplement form. Research published in Nutrition Research shows magnesium supplementation improves sleep quality and sleep duration in people with magnesium deficiency and people with sleep issues.
Other ways to keep your immune system in tip-top shape
Beyond getting a good night's sleep, here are some additional tips to support your immune system and protect yourself against illness:
- Do your best to relax."Stress is your body's biggest immune system hijacker," says Gray. While it's difficult to stay calm in such a trying time, it's worth the effort—for your health's sake. We've already mentioned yoga and meditation, two proven stress-relievers, but other activities can help you relax too. One such activity: Taking a warm bath before bed. The temperature cool-down you experience after a warm bath primes your mind and body for sleep, per research out of Gunma University in Japan. Here are other nighttime activities to help you relax.
- Eat plenty of nutrient-rich foods. Nutrition plays a crucial role in supporting your immune system, says Gray. One of the best things you can do is cut back on sugar, she says. Here's why: A study published in the American Journal of Clinical Nutrition finds that consuming 75 to 100 grams of sugar—say, two cans of soda—can suppress your body's immune functions. (If you love soda, Gray suggests switching to flavored seltzer, like La Croix, which doesn't contain any sugar). Beyond curbing your sugar intake, make sure to load up your plate with plenty of fruits and vegetables to get your fill of immune system-supporting vitamins, minerals, and antioxidants. An easy way to up your fill of fruits and vegetables is by throwing them into a smoothie.
- Take care of your gut."Functional medicine providers like myself believe that the root cause of many illnesses starts with poor gut health," says Gray, "so we want to make sure we're improving gut health." You can keep your gut healthy with probiotics, live microorganisms that promote healthy gut bacteria. A study published in the journal Gut shows that probiotics may help boost your immune system by hindering the growth of bad bacteria in your gut, while a study published in the British Journal of Nutrition finds that probiotics may reduce the duration of respiratory infections in children and adults.
- Exercise regularly. While working out is more challenging now that gyms across the country have temporarily shuttered their doors, you can still work up a sweat at home—and there's good reason to do so. Research shows regular, moderate exercise is beneficial to your immune system. That said, Gray warns that too much exercise can have a negative impact on your immune system. "There have been many research articles showing that over-exercising or over-training can negatively impact your immune system," says Gray, "so you'll be at greater risk of getting an upper respiratory infection." Aim for no more than 60 minutes of moderate to vigorous exercise per day.
- Wash your hands thoroughly—and often. You've likely heard this advice a whole lot lately, but it's worth repeating. It's crucial to wash your hands to prevent getting sick. As the Centers for Disease Control and Prevention (CDC) notes, when you touch your eyes, nose, or mouth—which many of us do without realizing—germs can get into your body. Plus, you can spread germs by touching objects with unwashed hands. A study published in Tropical Medicine and International Health shows that hand-washing lowers the risk of respiratory infection. The CDC recommends washing your hands with soap and water for at least 20 seconds. Twenty seconds seem like forever? Here's a fun list of songs to sing to yourself while you're sudsing up.
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