Recent research has revealed that individuals who identify as night owls, or those with a late chronotype, may face a higher risk of developing type 2 diabetes, independent of lifestyle factors.
Traditionally, late chronotype has been associated with poorer lifestyle habits, but new findings presented at the Annual Meeting of the European Association for the Study of Diabetes (EASD) suggest that the risk is more closely tied to biological factors.
Higher Risk for Late Chronotypes
Data from the Netherlands Epidemiology of Obesity study, involving nearly 5,000 participants, found that those with a late chronotype not only had a 55% higher risk of type 2 diabetes but also showed increased levels of body fat, particularly around the waist and liver. This was after controlling for lifestyle factors like diet, physical activity, and sleep quality. Researchers noted that this elevated risk is independent of these behaviors, suggesting other underlying mechanisms, such as circadian misalignment, may play a role.
Why Night Owls Are at Higher Risk
Lead researcher Jeroen van der Velde, PhD, of Leiden University Medical Centre, noted that while previous studies focused on lifestyle factors like smoking and physical inactivity, this new study points to biological factors contributing to the risk. "Abdominal obesity, such as larger waistlines and more visceral fat, may be key contributors to the increased metabolic risk in late chronotypes," Van der Velde explained.
The researchers believe that circadian rhythm, or internal body clock misalignment, may be a significant factor. Since modern society operates primarily on early schedules, night owls are often forced to adapt to a routine that doesn’t align with their natural sleep patterns. This misalignment can lead to metabolic disturbances, increasing the risk of obesity and diabetes.
The Role of Meal Timing and Circadian Rhythm
In addition to the circadian disruption, the timing of food intake may further exacerbate the issue. People with late chronotypes tend to eat later in the evening, and this has been linked to poorer metabolic health in other studies. While this particular study did not measure meal timing, researchers believe it could be another factor driving the increased risk of diabetes.
Health Impact of Social Timings
The societal emphasis on early work and school hours leaves late chronotypes at a disadvantage. Dr. Maria Knobel, a medical expert not involved in the study, noted, "Our society is built around early risers, which forces night owls to adjust their natural rhythms. This can lead to inconsistent sleep patterns, meal timing, and physical activity, contributing to negative health effects."