Study finds late‑night eating by night owls raises body fat and metabolic risk

A research project involving 287 healthy women aged 18‑45 in Europe and New Zealand examined how sleep chronotype influences metabolism. Participants were classified as morning types (early birds) or evening types (night owls) using the Munich Chronotype Questionnaire and tracked for five days. While total daily calories were similar, night owls consumed more food between 20:00 and 03:00, whereas early birds ate earlier, between 03:00 and 10:00.

The analysis showed that night owls had higher body‑mass indexes, greater body‑fat percentages, increased abdominal (android) fat, and less favourable cholesterol and blood‑sugar markers. Researchers attribute the difference to the body’s reduced ability to process nutrients during its rest phase. The study’s co‑authors recommend limiting food intake to at least two to three hours before bedtime rather than attempting to overhaul natural sleep patterns.

The findings are being discussed as a potential lever for digital health and workplace wellness programs, where timing‑based nutrition data could complement existing wearable‑based sleep and activity monitoring.