How Fast Do “Owls” and “Larks” Eat?

Abstract

Chronotype is a reflection of an individual’s preference for sleeping, eating and activity times over a 24 h period. Based on these circadian preferences, three chronotype categories have been identified: morning (MC) (lark), intermediate (IC) and evening (EC) (owl). Chronotype categories have been reported to influence dietary habits; subjects with EC are more prone to follow unhealthy diets. In order to better characterize the eating habits of subjects with obesity belonging to three different chronotype categories, we investigated eating speed during the three main meals in a population of subjects with overweight/obesity. For this purpose, we included 81 subjects with overweight/obesity (aged 46.38 ± 16.62 years; BMI 31.48 ± 7.30 kg/m2) in a cross-sectional, observational study. Anthropometric parameters and lifestyle habits were studied. Chronotype score was assessed using the Morningness–Eveningness questionnaire (based on their scores, subjects were categorized as MC, IC or EC). To investigate the duration of main meals, a dietary interview by a qualified nutritionist was conducted. Subjects with MC spend significantly more time on lunch than subjects with EC (p = 0.017) and significantly more time on dinner than subjects with IC (p = 0.041). Furthermore, the chronotype score correlated positively with the minutes spent at lunch (p = 0.001) and dinner (p = 0.055, trend toward statistical significance). EC had a fast eating speed and this, in addition to better characterizing the eating habits of this chronotype category, could also contribute to the risk of developing obesity-related cardiometabolic diseases.