Among the diabetic population obesity is common. Having a preference to evenings has been linked to increased obesity risks, research is thin regarding the phenomenon among patients with type 2 diabetes. The team wanted to determine if morning or evening lifestyle choices was associated with increased BMI for patients with type 2 diabetes, and what factors contributed.
210 nonshift workers with type 2 diabetes were recruited as participants in this study. Questionnaires were filled out to assess day time preference asking about times going to bed, waking up, amount of exercise, how much time reading, working, etc. Questionnaire scores range from 13 indicating extreme night preference to 55 indicating extreme day preference. For this study night owls scored less than 45, morning birds scored higher than 45.
Participants were individually interviewed regarding mealtimes, caloric intake was determined via self reported food recalls. BMI and weight measurements were individually calculated for each participant. Sleep quality and duration were also measured by questionnaire and self reports. Average sleep reported was 5.5 hours per night, caloric intake on average was 1,103 kcal/day. BMI average was 28.4 kg/m2. 97 were night owls and 113 were early birds.
Early birds consumed breakfast between 7-8:30AM, with night owls between 7:30-9AM. Early birds had earlier meal times for all meals. Researchers found that having more of a night owl preference was associated with higher BMIs. Caloric intake and dinner and lunch times were not associated with higher BMIs in this study. Early bird preferences were associated with earlier breakfast meal times and lower BMI by that of .37 kg/m2.
Researchers say this is a novel risk factor associated with higher BMIs among patients with type 2 diabetes. It was not determined if eating earlier breakfast will help body weight in this population. Later meal times may misalign internal clocks which play roles in circadian regulation. Misalignment of circadian regulation leads to energy metabolism dysregulation according to prior studies.
