Nutrition Notes

Sleep-Immune Crosstalk: Impact on Sleep-Deprived Health-Care Workers

Times are undoubtedly challenging as we traverse life during a global pandemic while trying our best to stay healthy. Health-care workers are often burning the candle at both ends during this pandemic, as many work around the clock to accommodate increased demands and a higher influx of patients. Combined with a lack of sleep, the ongoing physical, emotional and mental challenges that health-care workers are facing during this pandemic can increase their vulnerability to stress and burnout, and their susceptibility to infections, requiring extra support to bolster immune health. 

Sleep problems are already common complaints among health-care workers. According to a cross-sectional study conducted on 925 healthy professionals in the health-care industry, results showed that only 57% were “good sleepers” and there was a significant association between poor sleep quality and lower self-rated health. Lack of sleep and/or poor quality of sleep suppresses the immune system, which can make an individual more likely to catch a cold or virus. Alcohol misuse, stressful jobs, poor diet, lack of exercise and psychological stressors have detrimental effects on sleep quality. The global pandemic “is causing millions of people to lose sleep and that can come at a major cost to your overall health and well-being,” including the negative effect on immunity by increasing our body’s production of inflammatory cytokines, according to a Sleep Medicine specialist at the University of Kentucky.

Sleep-Immune Crosstalk

It is well-known in research that our immune systems are significantly influenced by circadian rhythms and the 24-hour clock of our bodies, as evidenced by systemic vacillations in immune parameters. “Sleep and immunity are bidirectionally linked,” according to the authors of a review on sleep and immunity. Immune system provocation, which occurs during an infection, alters sleep. Our sleep impacts the innate and adaptive immune system in a “sleep-immune crosstalk,” where it seems that the two systems are talking to each other. Sleep has been shown to reduce overall risk of infection, improve infection outcome and vaccination responses. Sleep also “appears to promote inflammatory homeostasis through effects on several inflammatory mediators.” Elevations in these pro-inflammatory cytokines, due to prolonged sleep deprivation, are associated with chronic conditions, such as diabetes, dementia and cardiovascular disease, which may then lead to an even greater susceptibility to infection because the immune system is on alert all the time, which disrupts the host defense.

Health-care workers need to prioritize sleep and maintain a healthy sleep routine (just like the rest of us) to support a healthy immune response. Basic strategies for improving sleep quality include avoiding caffeine and alcohol, eliminating screen use within an hour of bedtime, cutting back on unhealthy fats and refined foods that are high in sugar, and finding healthy ways to manage stress and anxiety (e.g., meditating, journaling, engaging in daily physical activity and psychotherapy). Health-care workers may benefit from daily nutritional supplementation to support good sleep and a healthy immune system. Not only is supplemental melatonin helpful for promoting restful sleep, but it has also been shown in recent animal studies to reduce viral load and downregulate oxidative injury, immune cell response and inflammatory cytokines (e.g., interleukin-6, tumor necrosis factor-α) and their production in the lungs. L-theanine, GABA, passionflower, lemon balm, valerian root, skullcap, ashwagandha and magnesium are other compounds that support restorative sleep, a healthy stress response, and an overall sense of calm.  

In addition to managing healthy sleep patterns, there are ways to help bolster the immune system directly via dietary, lifestyle and nutraceutical approaches. As mentioned in a previous article, vitamin D supplementation may be a cost-effective intervention that lowers the risk of respiratory tract and viral infections; deficiencies are linked with a higher prevalence of contracting the novel coronavirus, according to a randomized controlled trial. Beta-glucans have also demonstrated protective effects against upper respiratory tract infections due to their immunomodulatory and cytoprotective properties. Dietary selenium is shown to possess antiviral properties; higher serum levels have been associated with increased recovery rates for the novel acute respiratory syndrome. As always, health-care workers may consider managing optimal intakes of vitamin C, quercetin and zinc (to shield against infection) and following an anti-inflammatory diet rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from omega-3 fatty acids (substrates of specialized pro-resolving mediators that may help reduce viral replication).

By Caitlin Higgins, MS, CNS, LDN