Is sunlight enough for sufficient vitamin D status in children and adolescents? A survey in a sunny region of southern Italy

Is more prolonged sun exposure associated with healthier life habits and obesity indicators in Portuguese children?

OBJECTIVES

Sun exposure seems to have an indirect effect on the development of obesity through vitamin D synthesis in the skin, the primary source of this vitamin. The present study aimed to investigate associations among sun exposure time, obesity indicators, and lifestyle habits in children.

METHODS

A total of 4755 children (3-10 years; 49.86% boys) from the north, center and south-central Portugal were included in the present study. During 2016/2017 children's sun exposure time, screen time, time devoted to the practice of physical activity and active play were collected through standard questionnaires answered by parents. Statistical analyses were conducted to investigate differences among sun exposure time according to the sex, age, obesity indicators and lifestyle habits.

RESULTS

Linear regression analysis showed that sun exposure time presented a negative association with Body Mass Index (β = -0.09, 95% CI: -0.18; -0.003; p = .042), body fat % (β = -0.31, 95%; CI: -0.54; -0.07; p = .010), computer time (β = -0.08, 95% CI: -0.12; - 0.05; p < .0001) and a positive association with active play time (β = 0.22, 95% CI: 0.17; 0.27; p < .0001) and total time of physical activity practice (β = 10.01, 95% CI: 4.52; 15.20; p < .0001).

CONCLUSIONS

The results reinforce the need for future guidance on the ideal sun exposure time, especially in children, who are at risk for vitamin D deficiency. Standardization of criteria for classifying optimal sun exposure time in this age group, considering the parameters that affect vitamin D status, such as age and seasonality, should be considered when planning future guidelines.

Adherence to Dietary Recommendations of 7-Year-Old Children from a Birth Cohort in Friuli Venezia Giulia, Italy

Few Italian and European studies have assessed adherence to dietary recommendations in primary school children using dietary records. No Italian studies have provided an index-based nutritional adequacy assessment. We provided a comprehensive overview of dietary intake in 381 7-year-old children from NAC-II cohort study, Friuli Venezia Giulia (Italy). Energy, macro-, and micronutrient intakes were derived from 3-day dietary records. Standard (median and percentage) and index-based (Nutrient Adequacy Ratio (NAR) and Mean Adequacy Ratio (MAR)) approaches were used to evaluate adequacy to Italian dietary reference values at nutrient- and overall-diet-level. Percentage contribution of macronutrients to energy intake (%En) was unbalanced towards total fats and protein. In 25% of children, total fats intake exceeded the reference intake upper limit. In ~63% of children, protein intake was at least doubled in their child-specific population reference intake. Median intakes of sodium (1.7 g/day), saturated fatty acids (12.2 %En), and soluble carbohydrates (19.4 %En) exceeded the suggested dietary target in most (65–84%) children. Inadequacy was also observed for micronutrients, with median NARs ranging from 0.11 (vitamin D) to 0.90 (zinc). The median MAR was 0.75 (0.69–0.79), with 1 indicating optimal overall dietary intake. In conclusion, the enrolled children showed suboptimal intakes of several macro- and micronutrients, in line with Italian and European studies on primary school children. Based on the current findings, public health interventions may be targeted to specific nutrients or subpopulations.