Evidence map›Paper›PMID 42764707›Full record

ArticleAmerican journal of human biology : the official journal of the Human Biology Council2026

Sleep Duration and Sun Exposure in Portuguese Children: Associations With Obesity Indicators.

Elizabete A Dos Santos, Aristides Machado-Rodrigues, Daniela Rodrigues, Maria-Raquel G Silva, Helena Nogueira, Cristina Padez

Abstract read
In one paragraph

Article in American journal of human biology : the official journal of the Human Biology Council, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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3 · Its place in the literature

Who cites it

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No citing paper in PubMed yet.

4 · The record

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5 · Who and what money

Authors and funding

6 authors.

Elizabete A Dos SantosResearch Centre for Anthropology and Health, Department of Life Sciences, University of Coimbra, Coimbra, Portugal.ORCID https://orcid.org/0000-0001-9201-4095
Aristides Machado-RodriguesResearch Centre for Anthropology and Health, Department of Life Sciences, University of Coimbra, Coimbra, Portugal.ORCID https://orcid.org/0000-0002-7169-8034
Daniela RodriguesResearch Centre for Anthropology and Health, Department of Life Sciences, University of Coimbra, Coimbra, Portugal.ORCID https://orcid.org/0000-0002-4559-4303
Maria-Raquel G SilvaResearch Centre for Anthropology and Health, Department of Life Sciences, University of Coimbra, Coimbra, Portugal.ORCID https://orcid.org/0000-0001-8170-3119
Helena NogueiraResearch Centre for Anthropology and Health, Department of Life Sciences, University of Coimbra, Coimbra, Portugal.ORCID https://orcid.org/0000-0001-5724-3538
Cristina PadezResearch Centre for Anthropology and Health, Department of Life Sciences, University of Coimbra, Coimbra, Portugal.ORCID https://orcid.org/0000-0002-1967-3497

Funding

COMPETE 2020, Portugal 2020, FEDER, and FCTFundação para a Ciência e a Tecnologia PTDC/DTP-SAP/1520/2014
6 · The paper itself

Abstract

introductionSleep duration, sun exposure, and obesity are important and potentially interconnected factors in child health. In this study, we aimed to analyze the associations between sleep duration, sun exposure, and obesity indicators in Portuguese children.

methodsThis cross-sectional study included 4755 children aged 3-10 years from public and private schools across Portugal. Parents reported children's sleep duration, sun exposure, screen time, active play, and physical activity using validated questionnaires. Trained professionals measured weight and height to calculate Body Mass Index (BMI) and assessed skinfold thickness to estimate body fat percentage (%BF). Multiple linear regression analyses, stratified by sex and adjusted for demographic, behavioral, and anthropometric factors, analyzed associations between sun exposure and sleep duration.

resultsIn partially adjusted models (Model 1), negative associations persisted among boys, and positive associations emerged in girls for average sleep duration (β = 2.11; 95% CI: 0.25 to 3.96; p = 0.026) and weekdays (β = 2.40; 95% CI: 0.47 to 4.33; p = 0.015). In fully adjusted models (Model 2), the negative association remained only for boys on Sundays (β = -4.57; 95% CI: -8.22 to -0.91; p = 0.014), with no significant associations in girls.

conclusionsSun exposure exhibits modest, sex-specific associations with sleep duration in children. These findings emphasize the importance of considering behavioral and environmental factors when designing interventions to promote healthy sleep, support growth, and prevent childhood obesity.

Indexed as

Pediatric ObesitySleepSleep DurationSunlightChildChild, PreschoolCross-Sectional StudiesFemaleHumansMalePortugalchildhood obesitychildrenpediatric public healthsleep durationsun exposure

Identifiers

PMID42764707
PMCPMC13591200

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.