Night owls linked to higher obesity and metabolic disorder risk

A new observational study of 287 women aged 18‑45 from New Zealand, Europe and the Pacific, published in the journal Frontiers, found that individuals who naturally stay up late and wake up late (chronotype “night owls”) tend to have poorer dietary habits, higher body‑mass index, larger waist and hip measurements and greater visceral and abdominal fat compared with morning‑type and intermediate‑type participants. The night‑owl group also consumed more calories in the evening, chose less‑healthy foods and showed less‑favourable blood‑sugar and triglyceride levels, factors that may raise the risk of type‑2 diabetes and cardiovascular disease.

Participants provided blood samples, completed questionnaires on sleep habits and chronotype, and wore accelerometers to record activity and sleep patterns. While the findings highlight a correlation between a late chronotype and increased metabolic risk, the researchers stress that causality cannot be established and call for further studies to clarify how sleep timing and eating behaviours jointly affect long‑term health.