Research

Hormonal

Chronic circadian disruption, modeled by housing mice in incongruous 20-hour light/dark cycles, causes accelerated weight gain, obesity, and metabolic dysregulation (elevated insulin and leptin) despite unchanged food consumption.

If you work shifts or have irregular sleep/wake cycles, your body may gain weight and develop insulin resistance even if you don't change your diet. This is because your internal biological clock is desynchronized from your environment. Prioritizing consistent sleep-wake times and light exposure may help mitigate these metabolic risks.

GoodSupportsHIGH confidence
Housing in these conditions results in accelerated weight gain and obesity, as well as changes in metabolic hormones... CD mice show a gradual increase in body weight that becomes apparent after only 4–5 wk... These physiological changes are accompanied by remodeling of neocortical neuronal structure... Interestingly, these effects occur even though no differences in overall food consumption were detected between groups
Ilia N. Karatsoreos et al. · Proceedings of the National Academy of Sciences · 2011

Why this rating

Strong experimental evidence in a controlled animal model with clear statistical significance, though translation to humans is noted as unknown.

Source

Disruption of circadian clocks has ramifications for metabolism, brain, and behavior

Ilia N. Karatsoreos et al. · Proceedings of the National Academy of Sciences · 2011

DOI 10.1073/pnas.1018375108

mechanism_only · n=50Cited 553×
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DOI resolved against Crossref · corpus check 2026-06-10

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