Poor vitamin D status increases the risk of anemia in school children: National Food and Nutrition Surveillance

Improvement of vitamin D status through consumption of either fortified food products or supplement pills increased hemoglobin concentration in adult subjects: Analysis of pooled data from two randomized clinical trials

Background: It is documented that vitamin D may have a role in erythropoiesis as its deficiency is accompanied by an increased risk of anemia. Aim: This study aimed to examine whether improvement of vitamin D status through daily consumption of either fortified foods or supplements could impinge on certain hematologic parameters in adults. Methods: We pooled data from our two separate clinical trials and made five experimental groups. As part of their usual diet, one group consumed 500 mL/day of yogurt drink fortified with 1000 IU of vitamin D (D-yogurt, n = 27) whereas one group consumed 500 mL/day of the plain yogurt drink (P-yogurt, n = 27). In addition three other groups consumed either 50 g/day bread fortified with 1000 IU of vitamin D (D-bread) or supplement containing 1000 IU vitamin D (D-supplement, n = 27) or placebo (placebo, n = 27). Biochemical measurements were performed before and after the intervention. Results: In all three vitamin D-supplemented groups, serum 25(OH)D concentration increased after the intervention period, which was interestingly accompanied by a significant increment of hemoglobin (D-yogurt, p < 0.001, D-bread, p = 0.003, D-supplement, p < 0.001). Analyses indicated that among participants in vitamin D-intervention groups, being in D-yogurt group was more favourable predictor of improvement in hemoglobin concentrations compared with the placebo (p < 0.001), D-bread (p = 0.045) and P-yogurt (p = 0.001). Conclusion: Improvement of vitamin D status via regular intake of either vitamin D-fortified food products or supplements can result in a significant increment of hemoglobin in adult subjects. This finding has very important clinical as well as public health implications.

Formulation Strategies for Improving the Stability and Bioavailability of Vitamin D-Fortified Beverages: A Review

Vitamin D is a lipophilic bioactive that plays an important role in bone health. Fortification of beverages, such as milk, fruit juices, teas, and vegetable drinks, could be an efficient strategy to prevent vitamin D deficiency and its associated effects on health. This review summarizes the current understanding of beverage fortification strategies with vitamin D and the resulting effects on the stability, bioaccessibility, and sensory properties of the formulated products. The direct addition technique has been the conventional approach to fortifying beverages. In addition, encapsulation has been pointed out as a desirable delivery approach to increase stability, preserve bioactivity, and enhance the absorption of vitamin D in beverage systems. The literature reports the potential applicability of several methods for encapsulating vitamin D in beverages, including spray drying, micro/nanoemulsions, nanostructured lipid carriers, liposomes, and complexation to polymers. Some of these delivery systems have been assessed regarding vitamin D stability, but there is a lack of kinetic data that allow for the prediction of its stability under industrial processing conditions. Moreover, in some cases, the applicability of some of these delivery systems to real beverages as well as the in vivo efficacy were not evaluated; thus, fortification strategies with a global outreach are lacking.

Association of Helicobacter pylori Infection with Vitamin D Deficiency in Infants and Toddlers

Helicobacter pylori (H. pylori), a gram-negative pathogen, has been shown to colonize multiple organs and cause various forms of extra-gastrointestinal diseases. The association of H. pylori infection with vitamin D status in apparently healthy children remained unclear; therefore, we investigated the relationship between vitamin D and H. pylori infection among apparently healthy infants and toddlers. In this large cross-sectional study, the examination data of children were collected from January 2013 to September 2017 in the Center for Children's Health Care. Among these children, 6,896 infants and toddlers were screened for our study. Helicobacter pylori infection and vitamin D status were the main indicators, and micronutrients (zinc, iron, copper, magnesium), and growth parameters (height, weight, and weight for age Z score [WAZ], height for age Z score [HAZ]) were also analyzed in this study. Among the 6,896 infants and toddlers, the detection rate of H. pylori seropositivity was 30.6%. The prevalence of vitamin D deficiency in H. pylori seropositive and seronegative groups was 20.7% and 12.1%, respectively (P < 0.001). The logistic regression analysis suggested children with H. pylori-positive antibody were 2.06 times more likely to be vitamin D deficient compared with children who had negative H. pylori antibody (odds ratio: 2.06; 95% CI: 1.77, 2.38) after controlling for confounding factors. These data suggested that there was a significant association between H. pylori seropositivity and vitamin D deficiency in children aged 6-36 months, which would make a contribution to the treatment and monitoring of vitamin D deficiency and H. pylori infection.

The Effect of Vitamin D3 Supplementation on Hepcidin, Iron, and IL-6 Responses after a 100 km Ultra-Marathon

Deficiencies in iron and vitamin D are frequently observed in athletes. Therefore, we examined whether different baseline vitamin D₃ levels have any impact on post-exercise serum hepcidin, IL-6 and iron responses in ultra-marathon runners. In this randomized control trial, the subjects (20 male, amateur runners, mean age 40.75 ± 7.15 years) were divided into two groups: experimental (VD) and control (CON). The VD group received vitamin D₃ (10,000 UI/day) and the CON group received a placebo for two weeks before the run. Venous blood samples were collected on three occasions-before the run, after the 100 km ultra-marathon and 12 h after the run-to measure iron metabolism indicators, hepcidin, and IL-6 concentration. After two weeks of supplementation, the intervention group demonstrated a higher level of serum 25(OH)D than the CON group (27.82 ± 5.8 ng/mL vs. 20.41 ± 4.67 ng/mL; p < 0.05). There were no differences between the groups before and after the run in the circulating hepcidin and IL-6 levels. The decrease in iron concentration immediately after the 100-km ultra-marathon was smaller in the VD group than CON (p < 0.05). These data show that various vitamin D₃ status can affect the post-exercise metabolism of serum iron.

Anemia and its associated factors among Adolescents in Kuwait

We estimated the prevalence of anemia among school children and investigated factors associated with this problem in Kuwait. A cross-sectional study was conducted on 1415 adolescents randomly selected from middle schools in Kuwait. Hemoglobin, iron, ferritin, folate and vitamin B₁₂, in addition to many other laboratory indicators, were measured in a venous blood sample. Data on risk factors for anemia were collected from parents and adolescents. Multiple logistic regression was used to investigate factors associated with anemia. The prevalence of anemia was 8.06% (95% CI: 6.69-9.60%), which was significantly higher among females compared to males (10.96% vs. 5.04%; p < 0.001). Mean (SD) Hb level was 133.7 (9.89) g/L and 130.00 (10.48) g/L among males and females, respectively (p < 0.001). The prevalence of mild, moderate and severe anemia was 5.94%, 1.91% and 0.21%, respectively. Gender, age, iron concentration and ferritin were associated with anemia in multivariable analysis. These data indicate that anemia among school children in Kuwait is of mild public health significance. Further reduction in anemia in school girls should focus on correcting iron deficiency. Surveillance systems for anemia may consider using a cut-off point that is specific for the method of blood sampling and the method of Hb measurement.

The Effect of Vitamin D Supplementation on Hepcidin, Iron Status, and Inflammation in Pregnant Women in the United Kingdom

Iron and vitamin D deficiencies are common during pregnancy. Our aim was to identify whether antenatal vitamin D₃ supplementation affects iron status (via hepcidin suppression) and/or inflammation. Using a subset of the UK multicenter Maternal Vitamin D Osteoporosis Study (MAVIDOS)-a double-blinded, randomized, placebo-controlled trial (ISRCTN82927713; EudraCT2007-001716-23)-we performed a secondary laboratory analysis. Women with blood samples from early and late pregnancy (vitamin D₃ (1000 IU/day from ~14 weeks gestation n = 93; placebo n = 102) who gave birth in the springtime (March⁻May) were selected as we anticipated seeing the greatest treatment group difference in change in 25-hydroxyvitamin D (25OHD) concentration. Outcomes were hepcidin, ferritin, C-reactive protein, and α1-acid glycoprotein concentration in late pregnancy (25OHD concentration was measured previously). By late pregnancy, 25OHD concentration increased by 17 nmol/L in the vitamin D₃ group and decreased by 11 nmol/L in the placebo group; hepcidin, ferritin, and inflammatory markers decreased but no treatment group differences were seen. In late pregnancy, positive relationships between 25OHD and hepcidin and 25OHD and ferritin in the placebo group were observed but not in the treatment group (group × 25OHD interaction, p < 0.02). Vitamin D₃ supplementation had no effect on hepcidin, ferritin, or inflammatory status suggesting no adjunctive value of vitamin D₃ in reducing rates of antenatal iron deficiency.