Hygiena 2012, 57(1):10-16

Sleep Duration in Relation to BMI in Czech Adults

Zlata Piskáčková¹, Tomáš Zdražil², Martin Forejt¹, Julie Bienertová Vašků³

¹ Masarykova univerzita, Lékařská fakulta, Ústav preventivního lékařství, Brno

² Masarykova univerzita, Lékařská a Přírodovědecká fakulta, Institut biostatistiky a analýz, Brno

³ Masarykova univerzita, Lékařská fakulta, Ústav patologické fyziologie, Brno

Sleep plays a significant role in overall health and in the quality of human life. It is not only important for mental and physical regeneration, but also for the normal functioning of metabolic processes, for the endocrine and immune systems. In modern society there is a gradual shortening of the length of sleep due to a number of factors. In the last decade a number of epidemiological studies suggest that sleeping less than 7 hours a day increases the risk of developing obesity, type 2 diabetes mellitus, hypertension, cardiovascular diseases, and depression and is associated with premature mortality. The aim of this study was to evaluate sleep duration and to assess the relationship between sleep duration and BMI in the adult population (n=478, 18 to 65 years). The method of data collection consisted of a 7-day record of the length of the sleep per day and anthropometric measurements. The results showed that the average sleep duration was 7.45 (±0.91) hours per day. However, 28% of adults slept less than a recommended 7 hours a day. The individuals aged 40-49 years slept statistically the shortest time (mean 7.2±0.80 hours). The risk of obesity increased indirectly with duration of sleep in this population, for sleep categories [<6.3 h], [≥6.3 to <8.3 h] and [≥8.3 h] the risk of obesity defined as BMI ≥30 kg/m² was 2 : 1.5 : 1.2 based on the relative frequencies of obese and non-obese participants. Individuals sleeping on average <6.3 hours were at 1.3 times higher risk of obesity than other individuals sleeping longer after adjusting for age, this conclusion was not statistically significant (OR=1.256, 95% CI: 0.631; 2.422). In terms of prevention of obesity, sufficient sleep appears to be an important protective factor especially in the present fast pace of life and the increasing number of obese individuals and it should be taken in account in addition to a healthy diet and adequate physical activity.

Keywords: sleep, obesity, Body Mass Index (BMI)

Received: July 2011; Accepted: January 2, 2012; Published: March 1, 2012  Show citation