ArticleScientific reports2015
Circadian rhythm phase shifts and endogenous free-running circadian period differ between African-Americans and European-Americans.
Article in Scientific reports, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 62 papers, 1 of them a synthesis that pooled it.
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Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
62 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Disrupting the clock: meta-analysis of irregular night shifts and migraine, proposing shift work migraine disorder with chronobiology strategies.Frontiers in neurology · 2025Pooled it
- Early chronotype with advanced activity rhythms and dim light melatonin onset in a rural population.Journal of pineal research · 2020Trial
- Trial
- Late evening room light and sleep restriction reduces the ability of bright morning light to phase advance adolescents' circadian clocks.Scientific reports · 2026Article
- Single-arm pilot study of racial differences in sleep extension intervention outcomes among middle-aged adults at risk for metabolic syndrome.Journal of behavioral medicine · 2026Article
- BAYESIAN RHYTHMIC MODEL FOR JOINTLY DETECTING CIRCADIAN BIOMARKERS AND PREDICTING MOLECULAR CIRCADIAN TIME IN HUMAN POST-MORTEM BRAIN TRANSCRIPTOME.bioRxiv : the preprint server for biology · 2026Article
- Tuned by time: the role of circadian rhythms in metabolic energy sensing and chronotherapy.Annals of medicine · 2025Review
- The relationship between sleep and circadian-sleep phase angles based on dim light melatonin onset predicted from light and activity data.Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine · 2025Article
- Sex Differences in Circadian Timing and Biological Night in Adolescents.Journal of biological rhythms · 2025Article
- Bayesian Covariate-Dependent Circadian Modeling of Rest-Activity Rhythms.Data science in science · 2025Article
- Chronic circadian misalignment accelerates sarcopenia progression in mice.Frontiers in physiology · 2025Article
- Mathematical Analysis of Light-sensitivity Related Challenges in Assessment of the Intrinsic Period of the Human Circadian Pacemaker.Journal of biological rhythms · 2024Article
- Inter-individual variations in circadian misalignment-induced NAFLD pathophysiology in mice.iScience · 2024Article
- Distribution of dim light melatonin offset (DLMOff) and phase relationship to waketime in healthy adults and associations with chronotype.Sleep health · 2024Article
- Midpoint of sleep is associated with sleep quality in older adults with and without symptomatic Alzheimer's disease.Sleep advances : a journal of the Sleep Research Society · 2024Article
- Individual light history matters to deal with the Antarctic summer.Scientific reports · 2023Article
- Desynchronizing the sleep---wake cycle from circadian timing to assess their separate contributions to physiology and behaviour and to estimate intrinsic circadian period.Nature protocols · 2023Review
- Stories from a life studying circadian rhythms and sleep.Sleep advances : a journal of the Sleep Research Society · 2023Article
- Racial and Ethnic Differences in Eating Duration and Meal Timing: Findings from NHANES 2011-2018.Nutrients · 2022Article
- Nighttime lights, urban features, household poverty, depression, and obesity.Current psychology (New Brunswick, N.J.) · 2022Article
2 more citing papers are in PubMed but not listed here.
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Authors and funding
4 authors.
Funding
Abstract
Successful adaptation to modern civilization requires the internal circadian clock to make large phase shifts in response to circumstances (e.g., jet travel and shift work) that were not encountered during most of our evolution. We found that the magnitude and direction of the circadian clock's phase shift after the light/dark and sleep/wake/meal schedule was phase-advanced (made earlier) by 9 hours differed in European-Americans compared to African-Americans. European-Americans had larger phase shifts, but were more likely to phase-delay after the 9-hour advance (to phase shift in the wrong direction). The magnitude and direction of the phase shift was related to the free-running circadian period, and European-Americans had a longer circadian period than African-Americans. Circadian period was related to the percent Sub-Saharan African and European ancestry from DNA samples. We speculate that a short circadian period was advantageous during our evolution in Africa and lengthened with northern migrations out of Africa. The differences in circadian rhythms remaining today are relevant for understanding and treating the modern circadian-rhythm-based disorders which are due to a misalignment between the internal circadian rhythms and the times for sleep, work, school and meals.
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