The Surprising Link Between Sleep and Inflammation, According to Experts

Meet the experts: Sarathi Bhattacharyya, M.D., a pulmonologist, sleep medicine specialist, and medical director of MemorialCare Sleep Disorders Center at Long Beach Medical Center in Long Beach, CA; Ana Krieger, M.D., M.P.H., the director of the Center for Sleep Medicine at NewYork-Presbyterian/Weill Cornell Medical Center and Weill Cornell Medicine; Morgan Soffler, M.D., an assistant professor of pulmonary, critical care, and sleep medicine at New York Medical College.

So, how do these processes work? Ahead, sleep experts break it down, plus the simple strategies that may help improve your sleep and lower inflammation at the same time.

“Chronic inflammation can absolutely interfere with good sleep,” says Morgan Soffler, M.D., an assistant professor of pulmonary, critical care, and sleep medicine at New York Medical College. “Chemical signals that are activated in inflammation can disrupt normal sleep architecture, causing sleep fragmentation. This can lead to unrefreshing sleep and sleepiness or fatigue during the day.” These chemical signals are called cytokines, which are small proteins released by the immune system during a normal inflammatory response. “These proteins serve as messengers for specific functions, including sleep regulation,” explains Dr. Krieger. “Some cytokines may increase wakefulness, while others may help us sleep. There are also certain cytokines that are pro-inflammatory, associated with symptoms of chronic inflammation and fatigue.”

During periods of chronic inflammation, regular cytokine production becomes disrupted, meaning the messages they are sending may become jumbled and ultimately worsen sleep. “Elevated cytokines cause symptoms that mimic those of sleep disorders and affect the quality of sleep,” says Dr. Bhattacharyya. “Studies have demonstrated elevated levels of certain cytokines in humans with insomnia, sleep apnea, and chronic fatigue syndrome.”

Inflammation may also interfere with hormone production in the brain, says Dr. Soffler, including those that regulate our sleep and wake cycles. “Hormones such as serotonin and dopamine are affected by inflammation, and their disruption can cause sleep fragmentation and less restorative sleep,” she explains.

Finally, symptoms of chronic inflammation, such as muscle aches, joint pain, headaches, and gastrointestinal issues, may also disrupt sleep, says Dr. Bhattacharyya, either preventing you from falling asleep or waking you up in the middle of the night.

Just as chronic inflammation may prevent you from getting restful sleep, not getting enough sleep may also increase inflammation. “Lack of adequate sleep may affect immune function regulation. For example, inflammation causes sleep loss, and inadequate or insufficient sleep triggers a systemic increase in inflammatory mediators, perpetuating the problem,” explains Dr. Krieger.

Sleep deprivation may also increase cytokine production, notes Dr. Bhattacharyya. “Studies in rodents have shown that sleep loss or deprivation can lead to changes in the blood-brain barrier and allow more inflammatory molecules to cross into the brain.”

Poor sleep is typically associated with lower levels of melatonin, the hormone that regulates your sleep-wake cycle (a.k.a. your circadian rhythm). “Interestingly, melatonin has been shown to have some anti-inflammatory effects,” says Dr. Soffler. So if melatonin levels drop in conjunction with poor sleep, those anti-inflammatory properties also vanish, paving the way for more inflammation.

A review published in Communications Biology found that poor sleep leads to a chronic inflammatory state that increases your risk of developing various cardiometabolic, autoimmune, and neurodegenerative conditions.

Smart lifestyle strategies may both help improve sleep and work towards reducing levels of inflammation in the body. “A holistic approach to improve our health and wellbeing can significantly impact the effects of inflammation on sleep. Also, by improving sleep, the inflammatory response may be attenuated, making it easier to cope with,” affirms Dr. Krieger.

The most powerful strategies include:

• Regular physical activity. “This is probably the most powerful tool we have for both sleep and inflammation,” says Dr. Soffler. Aim for the Centers for Disease Control and Prevention-recommended 150 minutes of moderate intensity exercise per week.
• Better sleep hygiene. “Strategies to improve sleep regulation, such as keeping a regular bedtime and morning routine, using relaxation approaches to help prepare for sleep, and ensuring that our sleep environment is adequate for sleep [are all beneficial],” says Dr. Krieger.
• A healthier diet. Dr. Soffler recommends avoiding excess alcohol consumption and minimizing your intake of ultra-processed foods to start.
• Stress reduction. “This is key for both sleep and inflammation,” Dr. Soffler says. Try mind-body activities like yoga or tai chi, Dr. Krieger suggests.
• Addressing underlying sleep disorders. If you suspect you may have a sleep disorder, such as sleep apnea, seeing a doctor and getting the appropriate treatment can go far, Dr. Soffler says.