Association between social jet lag, quality of diet and obesity by diurnal preference in Finnish adult population.

The evening type has been associated with unhealthy behaviors and adverse health outcomes, such as unhealthy dietary habits and obesity. Misalignment between biological and social rhythms, referred to as social jet lag (SJL), has been considered to explain these outcomes, because evening types are more prone to SJL. However, the existing evidence has been inconsistent and SJL by diurnal preference has hardly been examined. We examined the associations between SJL, the quality of the diet, and the prevalence of obesity by diurnal preference. This dataset included 6779 Finns (55% women, aged 25-74 years) from the National FINRISK 2012 and DILGOM 2014 studies. Diurnal preference was assessed with a shortened version of the Morningness-Eveningness Questionnaire (MEQ). SJL was calculated with the sleep-corrected formula (SJL