Vitamin D status in a sunny country: Where has the sun gone?

Unger, Marianna Durante; Cuppari, Lílian; Titan, Sílvia M. O.; Magalhães, Maria Cláudia T.; Sassaki, A L; Reis, Luciene M. dos; Jorgetti, Vanda; Moysés, Rosa Maria Affonso

doi:10.1016/j.clnu.2010.06.009

Cited by 99 publications

(105 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Other authors have also observed lower 25(OH)D concentrations in smokers (10,42). Although a negative correlation between the 25(OH)D concentration and obesity has been observed by various authors (5,8,43), this result was not produced in our study and others (44). The majority of the participants had BMI between 18.5 and 29.9 kg/m 2 (median 25.6 kg/m 2 ), whereas only 13.5% had BMI ≥ 30 kg/m 2 .…”

Section: Discussionmentioning

confidence: 84%

“…We can also speculate that the lack of a relationship between sun exposure index and 25(OH)D may be explained by the fact that our population, which has relative homogeneity, lives in a region where air quality exceeds the standards for several days out of the year, and air pollution can adversely affect vitamin D production in the skin (5,30,41).…”

Section: Discussionmentioning

confidence: 99%

“…However, a survey among Brazilian adults revealed high prevalence rates of hypovitaminosis D in the winter and in the summer (77% and 37%, respectively) (5). Similarly, an 86% prevalence rate of inadequate vitamin D status was reported in Brazilian postmenopausal women receiving vitamin D supplementation of 400 IU/day (11).…”

mentioning

confidence: 99%

“…Exposure to sunlight, which induces vitamin D synthesis in the skin, is an important determinant of vitamin D status, and several studies have shown that its production is influenced by a variety of factors, including skin pigmentation, clothing style, season and air pollution, among others (7)(8)(9)(10). Serum 25(OH)D concentration decreases with increasing age and body mass index (BMI) and increases with increasing intake of vitamin D and physical activity (5,8,9).…”

mentioning

confidence: 99%

“…Controversy exists regarding the optimum level of serum 25-hydroxyvitamin D [25(OH)D] in a healthy population. However, most experts agree that a serum 25(OH)D concentration of at least 30 ng/mL is the endpoint for skeletal health outcomes (1,2,5). Inadequate vitamin D status induces secondary hyperparathyroidism, which stimulates bone loss and subsequently increases the risk of osteoporosis and fractures (6).…”

mentioning

confidence: 99%

See 4 more Smart Citations

Modifiable factors of vitamin D status among a Brazilian osteoporotic population attended a public outpatient clinic

Camargo

Kunii

Hayashi

et al. 2014

Arq Bras Endocrinol Metab

View full text Add to dashboard Cite

In a cross-sectional study, 363 community-dwelling patients who sought specialized medical care were evaluated between autumn and spring in São Paulo, Brazil. Serum levels of 25(OH)D and parathormone (PTH), biochemical and anthropometric measurements, and bone density scans were obtained. The group was assessed using two questionnaires: one questionnaire covered lifestyle and dietary habits, skin phototype, sun exposure, medical conditions, and levels of vitamin D supplementation (cholecalciferol); the other questionnaire assessed health--related quality-of-life. Logistic regression and a decision tree were used to assess the association between the variables and the adequacy of vitamin D status. Results: The mean age of the overall sample was 67.9 ± 8.6 years, and the mean 25(OH)D concentration was 24.8 ng/mL. The prevalence of inadequate vitamin D status was high (73.3%), although 81.5% of the subjects were receiving cholecalciferol (mean dose of 8,169 IU/week). 25(OH)D was positively correlated with femoral neck bone mineral density and negatively correlated with PTH. In the multivariate analysis, the dose of cholecalciferol, engagement in physical activity and the month of the year (September) were associated with improvement in vitamin D status.

show abstract