Efficacy of Vitamin D interventional strategies in saudi children and adults

Oral vitamin D supplementation and body weight in children and adolescents: a systematic review and meta-analysis of randomized controlled trials

This study was designed to ascertain whether oral vitamin D supplementation (oral supplementation and fortified foods) is associated with changes in body weight measures in children and adolescents, using a systematic review and meta-analysis of randomized controlled trials (RCTs). PubMed, Scopus, Cochrane, and Web of Science databases were searched from inception to October 28, 2022. The mean difference and corresponding 95% confidence interval (CI) of interested outcomes were pooled using a random-effects model. Twenty-one RCTs were included in the meta-analysis, and the results showed a significant decrease in body mass index (BMI) following vitamin D supplementation in children and adolescents (n = 9 studies, 1029 participants; weighted mean difference: - 0.43 kg/m², 95% CI: - 0.79, - 0.08; P = 0.02; I² = 58.5%). Overall, oral vitamin D supplementation had no significant effect on body weight and other anthropometric indices, including fat mass, lean mass, waist circumference, BMI Z-score, and height. Although results of body weight changed to significant after sensitivity analysis (WMD = 0.39 kg, 95% CI = 0.01, 0.78; P = 0.04; I² = 0%, P-heterogeneity = 0.71), we also found significant weight gain in healthy pediatric population, and when the dose of vitamin D supplementation was up to 600 IU/day, the certainty of evidence was very low for weight, moderate for height and BMI, and low for the remaining outcomes.

CONCLUSION

Our results suggest that vitamin D supplementation may lead to a statistically significant weight gain in children and adolescents, while BMI was reduced. Although no significant change was observed in height, it seems vitamin D supplementation may elicit these changes by increasing skeletal growth; however, this remains to be verified. Further high-quality RCTs, with longer duration and larger sample sizes, are needed to yield more certain evidence in this regard.

WHAT IS KNOWN

• Available evidence indicates an inverse association between body weight/fat mass and vitamin D status in children and adolescents; however, findings regarding the effect of vitamin D supplementation on anthropometric measurements in children are controversial.

WHAT IS NEW

• Our results showed a significant decrease in BMI following vitamin D supplementation in children. • A significant weight gain also was observed after sensitivity analysis, and in healthy pediatric population, and when the dose of vitamin D supplementation was up to 600 IU/day.

Determinants and Effects of Vitamin D Supplementation in Postmenopausal Women: A Systematic Review

Hormonal fluctuations, excessive clothing covering, sunscreen use, changes in body fat composition, a vitamin D-deficient diet, and a sedentary lifestyle can all predispose postmenopausal women to vitamin D deficiency. An effective supplementation plan requires a thorough understanding of underlying factors to achieve the desired therapeutic concentrations. The objective of this study was to conduct a systematic review of the predictors that affect vitamin D status in postmenopausal women. From inception to October 2022, we searched MEDLINE, Embase, Web of Science, Scopus, and clinical trial registries. Randomized clinical trials of postmenopausal women taking supplements of vitamin D with serum 25-hydroxyvitamin D (25(OH)D) measurement as the trial outcome were included. Two independent reviewers screened selected studies for full-text review. The final assessment covered 19 trials within 13 nations with participants aged 51 to 78. Vitamin D supplementation from dietary and pharmaceutical sources significantly increased serum 25(OH)D to optimal levels. Lower baseline serum 25(OH)D, lighter skin color, longer treatment duration, and prolonged skin exposure were all associated with a better response to vitamin D supplementation in postmenopausal women.

Diagnosis of Low Bone Mass Density: Serological versus Radiological Methods

Context

Bone remodeling comprises balanced coupling of bone formation and resorption, and low bone mineral density (BMD) demonstrates high rates of bone resorption. Osteoporosis is a chronic asymptomatic disease with fragile bones and impending risk of fractures mediated by minor trauma. Whereas bone mineralization and integrity are determined by calcium and vitamin D, specific serum markers such as bone specific alkaline phosphatase (ALP) and osteocalcin (OC) play a vital role in bone formation.

Materials and Methods

Serum calcium, vitamin D, ALP, and OC levels were measured in 2,145 Saudi students aged 18–22 years at Umm Al-Qura University. The BMD was measured by dual-energy X-ray absorptiometry (DEXA), and the findings were statistically evaluated. The following statistics were utilized in the analysis: the SPSS software was used to record, tabulate, and statistically evaluate the results.

Results

Low BMD cases accounted for 27.46% of all cases investigated, with considerably higher serum calcium, bone-specific ALP, and OC levels compared to control cases, but significantly lower serum vitamin D levels. In low BMD instances, there was no association between serum markers and DEXA findings.

Conclusion

Serum indicators by themselves may be useful for screening and predicting patients at risk of osteoporosis, as well as assessing treatment response. The combination of serum markers and DEXA measures is more effective in detecting low BMD.

Decreasing prevalence of vitamin D deficiency in the central region of Saudi Arabia (2008-2017)

OBJECTIVE

Widespread vitamin D deficiency (serum 25-hydroxyvitamin D < 50 nmol/L) in Saudi Arabia (SA) has been documented, yet a time trend is needed to establish where the prevalence is headed. This study aims to fill this gap.

STUDY DESIGN AND SETTING

This cross-sectional series (N = 7360) were conducted in the central region of SA from 2008 to 2017. Participants of all ages were taken from multiple cohorts that included the Biomarker Screening in Riyadh (2008-2010; N = 1460), the Osteoporosis Registry (2014-2017; N = 1225), Gestational Diabetes Mellitus cohort (2014-2017, N = 281), Vitamin D School Project (2011-2017; N = 3039) and Prediabetes cohort (2012-2017; N = 1355) master databases.

RESULTS

Vitamin D deficiency in SA has a 10-year prevalence of 73.2 %. Between 2008-2017, the prevalence of vitamin D deficiency decreased from 87.1% to 64.7% for participants aged 18-40 years (p-trend<0.001), and from 86.2% to 45.7% in participants aged > 40 years (p-trend<0.001). During this period, vitamin D deficiency in females decreased from 80.1% to 69.6% (p-trend<0.001), whereas in males, it decreased from 93.2% to 49.3% (p-trend<0.001). Serum 25(OH)D was observed to have an overall increase of 2.2 ± 0.1 nmol/l (p < 0.001) along with the seasonally adjusted annual increase of 1.3 ± 0.2 nmol/l from 2008 to 2017 (p < 0.001).

CONCLUSION

The decreasing trend in vitamin D deficiency in SA across all demographics suggests successful public health campaigns over time. It will be interesting to investigate further whether the general improvement in the vitamin D status at the community level also translated in lesser incidences of vitamin d-related diseases over time.

Vitamin D status and its dietary and lifestyle factors in children during the first 5 years of life: A cross-sectional multicentre Jiangsu bone study

BACKGROUND

To explore the vitamin D status with its demographic and lifestyle factors including dietary, supplementation, and physical activity in 0-5 years old children.

METHODS

This was a large population-based cross-sectional multicentre study in which the children were recruited from 12 Children's Health Care Centers by a stratified cluster random-sampling method in 10 cities in Jiangsu Province, China.

RESULTS

A total number of 5289 children were investigated. The prevalence of vitamin D deficiency was 30.1%. The concentration of 25 hydroxyvitamin D was 64.0 (46.3-83.0) nmol mL^-1 after adjustment for covariates. Children with higher risk of vitamin D deficiency were more likely to be at older age, girls, survey conducted in spring, location in southern Jiangsu province, residence in urban, outdoor activity < 2 h day^-1 (all p < 0.05). Moreover, those with lower risk were more likely to be the number of parity ≥ 2 times, vitamin D supplementation from birth to 6 months, the initial time of vitamin D supplementation after birth ≤ 1 months, vitamin D and calcium supplementation in the last 3 months, and dose of vitamin D supplementation > 400 IU day^-1 (all p < 0.05). Children with preferences for sweets, meat consumption > 150.0 g day^-1 , milk consumption < 250 mL day^-1 , time of sleeping < 10 h day^-1 had higher risks of vitamin D deficiency. However, these relationships were affected by demographics.

CONCLUSIONS

Vitamin D status during the first five years of life was suboptimal and was associated with demographic and lifestyle determinants including milk, meat, sweets, vitamin D and calcium supplementation, sleeping and outdoor activity.

Hidden Hunger of Vitamin E among Healthy College Students: A Cross- Sectional Study

BACKGROUND

College students may have a risk of fat-soluble vitamin deficiencies due to unhealthy dietary habits, especially for vitamin A and E. They are important members of the human antioxidant network; deficiencies of these vitamins may increase the risk of many critical diseases.

OBJECTIVE

The current study was undertaken to determine the status of vitamin A and E in college students.

METHODS

Healthy college students were recruited, and fasting blood samples of them were collected and used for determining serum levels of retinol and α-tocopherol by the HPLC method.

RESULTS

We found that there was no vitamin A deficiency in college students. However, vitamin E deficiency existed in 34.5% of college students, especially in males. All the students had no vitamin E adequacy. In addition, our findings showed that BMI was inversely associated with serum α-- tocopherol, but not serum retinol.

CONCLUSION

These results suggest that vitamin E deficiency in college students should be given more attention, and it is necessary to consider using vitamin E supplements.

Vitamin D Deficiency and Associated Risk Factors in Women from Riyadh, Saudi Arabia

Vitamin D deficiency is an epidemic public health problem worldwide. It is common in the Middle East and is more severe in women. This cross-sectional study was conducted to assess vitamin D deficiency and associated risk factors in women living in Riyadh, Saudi Arabia. Serum 25-hydroxyvitamin D (25(OH)D) was measured in 166 women aged 30-65 years. Socio-demographic, lifestyle and health status characteristics, as well as intake of selected dietary supplements, were collected. Weight and height were measured. Vitamin D deficiency (25(OH)D < 20 ng/mL) was reported in 60.2% of participants. Mean of serum 25(OH)D was 20.7 ng/mL. Older age and taking the supplements of vitamin D, multi-vitamins or calcium were identified as factors that associated with a lower risk of hypovitaminosis D. A national strategy is needed to control a hypovitaminosis D crisis in Saudi Arabia. This could be accomplished by raising public awareness regarding vitamin D, regulating and enhancing vitamin D fortification and supplementation and screening vitamin D status among women at high risk.

Vitamin D Supplementation Modestly Reduces Serum Iron Indices of Healthy Arab Adolescents

Vitamin D deficiency has been shown to affect iron status via decreased calcitriol production, translating to decreased erythropoiesis. The present study aimed to determine for the first time whether vitamin D supplementation can affect iron levels among Arab adolescents. A total of 125 out of the initial 200 Saudi adolescents with vitamin D deficiency (serum 25(OH)D < 50 nmol/L) were selected from the Vitamin D-School Project of King Saud University in Riyadh, Saudi Arabia. Cluster randomization was done in schools, and students received either vitamin D tablets (1000 IU/day) (N = 53, mean age 14.1 ± 1.0 years) or vitamin D-fortified milk (40IU/200mL) (N = 72, mean age 14.8 ± 1.4 years). Both groups received nutritional counseling. Anthropometrics, glucose, lipids, iron indices, and 25(OH)D were measured at baseline and after six months. Within group analysis showed that post-intervention, serum 25(OH)D significantly increased by as much as 50%, and a parallel decrease of −42% (p-values <0.001 and 0.002, respectively) was observed in serum iron in the tablet group. These changes were not observed in the control group. Between-group analysis showed a clinically significant increase in serum 25(OH)D (p = 0.001) and decrease in iron (p < 0.001) in the tablet group. The present findings suggest a possible inhibitory role of vitamin D supplementation in the iron indices of healthy adolescents whose 25(OH)D levels are sub-optimal but not severely deficient, implying that the causal relationship between both micronutrients may be dependent on the severity of deficiency, type of iron disorder, and other vascular conditions that are known to affect hematologic indices. Well-designed, randomized trials are needed to confirm the present findings.

Effects of sunlight exposure and vitamin D supplementation on vitamin D levels in postmenopausal women in rural Thailand: A randomized controlled trial

BACKGROUND

Despite the abundant sunlight in Thailand, vitamin D deficiency is common in premenopausal and postmenopausal Thai women. Sunlight exposure is a natural way to increase one's intake of vitamin D. However, limited research has been conducted regarding natural exposure to sunlight as a strategy to improve vitamin D status in postmenopausal women.

OBJECTIVE

This study aimed to determine the effects of sunlight exposure compared with oral supplementation with vitamin D2 (weekly 20,000 IU) in combination with sunlight exposure on 25(OH)D levels.

METHODS

A 12-week randomized controlled trial was conducted in 52 postmenopausal women, age 50-70 years. The participants were randomized to either the sunlight exposure group or the sunlight exposure with vitamin D supplementation group. Serum 25(OH)D concentration and parathyroid hormone (PTH) were measured using standard assays at baseline and 12 weeks.

RESULTS

After 12 weeks, mean serum 25(OH)D had decreased from 32.3 to 29.7 ng/ml in the sunlight exposure group, but significantly increased in the combination group (from 29.9 to 32.4 ng/ml). At the end of the study, 25(OH)D levels were significantly higher in the sunlight exposure with vitamin D supplementation group compared with the sunlight exposure group. However, this difference was not observed in women aged >60 years. Serum PTH had decreased in both groups, but not to a significant extent.

CONCLUSION

A combination of weekly vitamin D2 supplementation at a dose of 20,000 IU with sunlight exposure is more effective than sunlight exposure alone in postmenopausal Thai women. Sunlight exposure alone is not sufficient to maintain 25-hydroxyvitamin D levels in this setting.