Paradoxical Response of Parathyroid Hormone to Vitamin D-Calcium Supplementation in Indian Children.

OBJECTIVES: To investigate the effect of oral vitamin D-calcium supplementation on serum intact parathyroid hormone (PTH), calcium, phosphorous, and alkaline phosphatase (ALK-P) concentrations in children with habitually low calcium intakes. STUDY DESIGN: In this follow-up study to a randomized controlled trial that aimed to assess the effect of vitamin D-calcium supplementation on immunity, data related to dietary intake, anthropometry, and biochemistry [serum 25(OH)D and bone profile] were collected from 178 children-79 in the vitamin D group and 99 in the non-vitamin D group. RESULTS: Dietary calcium to phosphorus intake ratio was 0.4:1. Baseline serum 25(OH)D concentration was 58.2 ± 10.9 nmol/L; 66% children were vitamin D sufficient and none deficient. After supplementation, vitamin D group, compared with the non-vitamin D group, had significantly (P < .05) greater 25(OH)D (83.9 ± 30.1 nmol/L vs 58.3 ± 15.7 nmol/L), significantly greater PTH (6.7 ± 3.6 pmol/L vs 5.5 ± 3.2 pmol/L), and positive correlation (rs = 0.24) between serum 25(OH)D and PTH (vs negative correlation [rs = -0.1] in non-vitamin D group). Mean concentrations of serum bone measures in the vitamin D group were calcium (2.2 ± 0.1 mmol/L), phosphorus (1.7 ± 0.2 mmol/L), and ALK-P (178.7 ± 40.7 IU/L). At follow-up, 1-year post-supplementation, in the vitamin D group, PTH concentrations continued to remain high (but not significantly different from levels at 6 months), with low normal serum calcium, high normal phosphate, and ALK-P in reference range. CONCLUSIONS: In children who are vitamin D sufficient but with habitually low dietary calcium intake, vitamin D-calcium supplementation paradoxically and significantly increased serum PTH concentrations with no apparent effect on other bone biochemistry. Chronic low dietary calcium to phosphorus ratio is likely to have caused this paradoxical response.

Randomized Control Trial Assessing Impact of Increased Sunlight Exposure versus Vitamin D Supplementation on Lipid Profile in Indian Vitamin D Deficient Men.

BACKGROUND: Despite abundance of sunshine in India, Vitamin D deficiency is common and therefore there is an increasing trend toward taking Vitamin D supplements either as prescription medicine or as a nutritional supplement. Studies have suggested that duration of sun exposure may influence serum lipid profile. OBJECTIVES: To study the effect of increased sunlight exposure versus Vitamin D supplementation on Vitamin D status and lipid profile in individuals with Vitamin D deficiency (25-hydroxyvitamin-D [25OHD] <50 nmol/L). DESIGN: A prospective, randomized open-label trial was carried out in apparently healthy Indian men (40-60 years). Based on 25OHD concentrations, individuals were divided into control (>50 nmol/L, n = 50) and intervention (<50 nmol/L, n = 100) groups. Individuals from intervention group were randomly allocated to two groups; either "increased sunlight exposure group" (n = 50, received at least 20 min sunlight exposure to forearms and face between 11 a.m. and 3 p.m. over and above their current exposure) or "cholecalciferol supplement group" (n = 50, received oral cholecalciferol 1000 IU/day). RESULTS: Significant increase in 25OHD concentrations was seen in both intervention groups (P < 0.01). Significant decrease in total cholesterol (TC), high-density-lipoprotein cholesterol (HDL-C), and low-density-lipoprotein cholesterol (LDL-C) was seen in individuals with increased sunlight exposure (P < 0.05). Cholecalciferol supplement group showed a significant increase in TC and HDL-C (P < 0.05) and insignificant increase in LDL-C. CONCLUSIONS: Increase in Vitamin D concentrations through sunlight exposure significantly reduced TC, LDL-C, and HDL-C concentrations, and cholecalciferol supplementation increased TC and HDL-C concentrations.

Assessing the population impact of low rates of vitamin D supplementation on type 1 diabetes using a new statistical method.

Vitamin D supplementation for all children <5 is recommended by the UK Department of Health for its skeletal effects. Vitamin D is also linked with a number of extra-skeletal effects; one of them being protection against type 1 diabetes. With a rapid increase in the incidence of type 1 diabetes and the associated costs, measures of curtailing the rapid increase of type 1 diabetes are needed. In this review, we look at type 1 diabetes using a statistical method (PIN-ER-t) and published data in an attempt to quantify the impact on the population of babies born in 2012 of increasing vitamin D supplementation rates. Calculations show that for the population of 729,674 babies born in England and Wales in 2012, 374 cases of type 1 diabetes (out of 1357 total predicted) could be prevented over 18 years if all were supplemented with vitamin D. This could lead to savings in excess of £62 million for the cohort. This piece of work adds to the argument for studying the potential link between vitamin D supplementation and type 1 diabetes further.