The connection between sleep and inflammation is a surprisingly potent, two-way street, according to sleep and pulmonary specialists. Chronic inflammation can disrupt sleep, and conversely, insufficient sleep can exacerbate inflammatory responses within the body.
“Sleep and the immune system and inflammation are closely connected,” explains 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, California. This relationship isn’t simply a correlation; it’s bidirectional, meaning each process actively influences the other.
Ana Krieger, M.D., M.P.H., director of the Center for Sleep Medicine at NewYork-Presbyterian/Weill Cornell Medical Center and Weill Cornell Medicine, elaborates on this interplay. “Chronic inflammation may affect sleep regulation, quality and duration, and these changes in sleep may, in turn, worsen inflammation.”
The mechanisms behind this connection involve the release of cytokines, modest proteins produced by the immune system during inflammation. Morgan Soffler, M.D., an assistant professor of pulmonary, critical care, and sleep medicine at Latest York Medical College, notes that these chemical signals can “disrupt normal sleep architecture, causing sleep fragmentation. This can lead to unrefreshing sleep and sleepiness or fatigue during the day.” Dr. Krieger adds that certain cytokines can either promote wakefulness or encourage sleep, but disrupted production during chronic inflammation leads to “jumbled” messaging.
Elevated cytokine levels have been observed in individuals with insomnia, sleep apnea, and chronic fatigue syndrome, according to Dr. Bhattacharyya. Inflammation can also interfere with the production of hormones like serotonin and dopamine, which are crucial for regulating sleep-wake cycles, leading to fragmented and less restorative sleep, Dr. Soffler explains.
Beyond the biochemical effects, the physical symptoms of chronic inflammation – muscle aches, joint pain, headaches, and gastrointestinal issues – can directly impede sleep, either preventing individuals from falling asleep or causing them to wake during the night, Dr. Bhattacharyya says.
The impact isn’t one-sided. Sleep deprivation can also trigger an increase in inflammation. Dr. Krieger explains that a lack of adequate sleep can affect immune function regulation, creating a cycle where inflammation causes sleep loss, and insufficient sleep then increases inflammatory mediators. Studies have shown that sleep loss can alter the blood-brain barrier, allowing more inflammatory molecules to enter the brain, according to Dr. Bhattacharyya.
Poor sleep is also typically associated with lower levels of melatonin, a hormone that regulates the circadian rhythm. Dr. Soffler points out that melatonin possesses anti-inflammatory properties, and its reduction during periods of poor sleep removes a natural defense against inflammation.
A recent review published in Communications Biology found that chronic sleep deprivation leads to a chronic inflammatory state, increasing the risk of developing cardiometabolic, autoimmune, and neurodegenerative conditions.
Experts recommend a holistic approach to address both sleep, and inflammation. Regular physical activity – aiming for at least 150 minutes of moderate-intensity exercise per week, as recommended by the Centers for Disease Control and Prevention – is considered a powerful tool. Improving sleep hygiene, including maintaining a regular sleep schedule, practicing relaxation techniques, and optimizing the sleep environment, is also crucial, according to Dr. Krieger. Dietary changes, such as reducing alcohol consumption and minimizing ultra-processed foods, are also recommended by Dr. Soffler.
Stress reduction techniques, like yoga or tai chi, can benefit both sleep and inflammation, Dr. Soffler and Dr. Krieger suggest. Finally, addressing underlying sleep disorders, such as sleep apnea, through medical diagnosis and treatment, can significantly improve both sleep quality and inflammatory markers, Dr. Soffler notes.