A Spain cohort study suggested that siesta duration is relevant in obesity/metabolic syndrome (MetS). Timing of nighttime sleep and eating, energy intake at lunch, cigarette smoking, and siesta location may be potential lifestyle mediators. The study included 3275 individuals (mean age 41 years, 78% women, and average BMI 31.1) with no diagnosed illnesses except for obesity. Thirty-five percent of participants usually took siestas (16% long siestas). Compared with the no-siesta group, long siestas (>30 minutes) were associated with higher values of BMI, waist circumference, fasting glucose, systolic blood pressure (SBP), diastolic blood pressure, and a higher prevalence of MetS (41%). In contrast, the probability of having elevated SBP was 21% lower in the short-siesta (≤30 minutes) group than in the no-siesta group. Smoking more cigarettes per day mediated 12% of the association of long siestas with higher BMI. Delays in nighttime sleep and eating schedules and higher energy intake at lunch (the meal preceding siestas) mediated the association between higher BMI and long siestas by 8%, 4%, and 5%, respectively. There was a trend that napping in bed (vs. sofa/armchair) mediated 6% of the association between long siestas and higher SBP. The study is in line with previous studies that have shown that short naps were not, but longer naps (>1 hour) were associated with higher cardiovascular risk and provides novel information on the potential mediating effect of some lifestyle factors among long siestas, obesity, and MetS. Source: https://onlinelibrary.wiley.com/
