It’s no secret that getting a good nights rest has many benefits, from preventing weight gain to improving memory consolidation. And a recent study has uncovered yet another benefit: sleep duration directly correlates with susceptibility to common colds.
In this study, 164 healthy participants monitored their sleeping patterns by wrist actigraphy and sleep diaries over seven days. After this period, the volunteers were administered the rhinovirus via nasal drops, and monitored for another 5 days to see whether they displayed cold symptoms.
Based on the findings of this study, participants who slept less than 6 hours a night were significantly more likely to develop a cold: 30% of adults became sick if the slept less than 6 hours a night, compared to less than 20% if you sleep more than 7 hours. While the mechanism for how sleep affects the immune system is still unclear, this study confirms yet another reason to get a good nights sleep.
Short sleep duration and poor sleep continuity have been implicated in the susceptibility to infectious illness. However, prior research has relied on subjective measures of sleep, which are subject to recall bias. The aim of this study was to determine whether sleep, measured behaviorally using wrist actigraphy, predicted cold incidence following experimental viral exposure.
Design, Measurements, and Results:
A total of 164 healthy men and women (age range, 18 to 55 y) volunteered for this study. Wrist actigraphy and sleep diaries assessed sleep duration and sleep continuity over 7 consecutive days. Participants were then quarantined and administered nasal drops containing the rhinovirus, and monitored over 5 days for the development of a clinical cold (defined by infection in the presence of objective signs of illness). Logistic regression analysis revealed that actigraphy- assessed shorter sleep duration was associated with an increased likelihood of development of a clinical cold. Specifically, those sleeping < 5 h (odds ratio [OR] = 4.50, 95% confidence interval [CI], 1.08–18.69) or sleeping between 5 to 6 h (OR = 4.24, 95% CI, 1.08–16.71) were at greater risk of developing the cold compared to those sleeping > 7 h per night; those sleeping 6.01 to 7 h were at no greater risk (OR = 1.66; 95% CI 0.40–6.95). This association was independent of prechallenge antibody levels, demographics, season of the year, body mass index, psychological variables, and health practices. Sleep fragmentation was unrelated to cold susceptibility. Other sleep variables obtained using diary and actigraphy were not strong predictors of cold susceptibility.
Shorter sleep duration, measured behaviorally using actigraphy prior to viral exposure, was associated with increased susceptibility to the common cold.