ArticleNutrition (Burbank, Los Angeles County, Calif.)2023
Influence of sunlight on the association between 25-hydroxyvitamin D levels and sleep quality in Brazilian adults: A population-based study.
Article in Nutrition (Burbank, Los Angeles County, Calif.), 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers.
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14 citing papers in PubMed, 22 citations in OpenAlex.
- Physiological, Metabolic, and Mitochondrial Adaptations to a One-Week Endurance Training Camp in Recreational Athletes: An Observational Study.Sports (Basel, Switzerland) · 2026Article
- Time worked in shifts and occurrence of drowsiness events while driving: attenuating effect of physical activity.BMC public health · 2025Article
- The role of sunlight in sleep regulation: analysis of morning, evening and late exposure.BMC public health · 2025Article
- Outdoor light spending time, genetic predisposition and incident Parkinson's disease: the mediating effect of lifestyle and vitamin D.Journal of health, population, and nutrition · 2025Article
- Association between vitamin D level and sleep quality in the elderly population: a prospective cohort study.Sleep & breathing = Schlaf & Atmung · 2025Article
- Review
- Association of cardiometabolic index with sleep quality in adults: a population‑based study.Scientific reports · 2024Article
- The association of sedentary time with sleep disturbances among the US population, 2005 to 2014.BMC public health · 2024Article
- The role of interaction between vitamin D and VDR FokI gene polymorphism (rs2228570) in sleep quality of adults.Scientific reports · 2024Article
- Association of serum 25-hydroxyvitamin D with cardiovascular and all-cause mortality in patients with chronic kidney disease: NHANES 2007‒2018 results.Clinics (Sao Paulo, Brazil) · 2024Article
- ED-71 Ameliorates Bone Loss in Type 2 Diabetes Mellitus by Enhancing Osteogenesis Through Upregulation of the Circadian Rhythm Coregulator BMAL1.Drug design, development and therapy · 2024Article
- High Prevalence and Risk Factors Associated with Vitamin D Deficiency Among Chinese Hospital Staff: A Cross-Sectional Study.International journal of general medicine · 2024Article
- Reliability and validity of the Chinese version of the sunlight exposure questionnaire.Frontiers in public health · 2024Article
- Organic Synthesis of New Secosteroids from Fucosterol, Its Intestinal Absorption by Caco-2 Cells, and Simulation of the Biological Activities of Vitamin D.Marine drugs · 2023Article
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Authors and funding
9 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
objectivesThis study aimed to evaluate the association of vitamin D with sleep quality during the COVID-19 pandemic and the influence of daily sunlight on this association.
methodsThis cross-sectional, population-based study among adults stratified by multistage probability cluster sampling was conducted from October to December 2020 in the Iron Quadrangle region of Brazil. The outcome was sleep quality, evaluated by the Pittsburgh Sleep Quality Index. Vitamin D (25-hydroxyvitamin D) concentrations were determined by indirect electrochemiluminescence and a deficiency was classified as 25(OH)D < 20 ng/mL. To assess sunlight, the average daily sunlight exposure was calculated and was classified as insufficient when less than 30 min/d. Multivariate logistic analysis was used to estimate the association between vitamin D and sleep quality. A directed acyclic graph was used to select minimal and sufficient sets of adjustment variables for confounding from the backdoor criterion.
resultsIn a total of 1709 individuals evaluated, the prevalence of vitamin D deficiency was 19.8% (95% CI, 15.5-24.9%), and the prevalence of poor sleep quality was 52.5% (95% CI, 48.6-56.4%). In multivariate analysis, vitamin D was not associated with poor sleep quality in individuals with sufficient sunlight. Moreover, in individuals with insufficient sunlight, vitamin D deficiency was associated with poor sleep quality (odds ratio [OR], 2.02; 95% CI, 1.10-3.71). Furthermore, each 1-ng/mL increase in vitamin D levels reduced the chance of poor sleep quality by 4.2% (OR, 0.96; 95% CI, 0.92-0.99).
conclusionsVitamin D deficiency was associated with poor sleep quality in individuals with insufficient exposure to sunlight.
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