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.

Beneficial effect of iron pot cooking on iron status.

OBJECTIVES: To develop iron rich snacks using locally available iron rich foods and analyze their iron content when cooked in iron pots. Further, the efficacy of the developed snacks, cooked in iron pots was examined on the hemoglobin status of pre-school children through a three month randomized trial. METHODS: Four iron rich snacks (mean iron content 2.1mg/serving) were cooked in iron pots and 27 preschool children (mean age 2.9 ± 0.9 y, 12 boys) were supplemented with the snacks for 4 mo. Anthropometry and dietary intake data were collected. Hemoglobin, serum iron and transferrin saturation were assessed. RESULTS: An increase of 16.2 % in the iron content was found in the snacks cooked in iron pots than cooked in Teflon coated non-stick pots. After 4 mo of supplementation, a significant increase of 7.9 % was seen in the hemoglobin of the children. CONCLUSION: This pilot study demonstrated that iron rich recipes cooked in iron pot have a beneficial effect on iron status of children. Therefore, such food based strategies have the potential to alleviate iron deficiency anemia not only in children but also in other vulnerable sections of society like in pregnant women.

Calcium bioavailability from a fortified cereal-legume snack (laddoo).

OBJECTIVE: Calcium intakes in underprivileged Indian children are often low. Improving calcium intake fortification of indigenous foods may be a viable strategy. The aim of this study was to evaluate calcium absorption, as judged by an acute increase in serum ionized calcium concentration, after ingestion of a calcium-fortified cereal-legume snack (laddoo). METHODS: Three groups of eight children (8-12 y old) with low habitual dietary calcium intake were recruited for the study. After an overnight fast, a calcium-fortified (500 mg of calcium carbonate) cereal-legume snack (laddoo) was given to group A, a similar but non-fortified snack was given to group B, and group C received calcium carbonate (500 mg) alone. Serum concentrations of ionized calcium and intact parathyroid hormone were measured at 0, 1, 2, 3, 4, and 5 h. RESULTS: In group A, a peak of 6% above baseline was observed at 1 h in serum ionized calcium, whereas group C showed a peak of 5.5% at 4 h and group B showed a small increase of 1.8% at 1 h. The change in area under curve of groups A and C were of similar order (4.6 and 5.5, respectively), whereas that of group B was significantly lower (0.82). Serum parathyroid hormone was lowest at 2 h in groups A and B and at 3 h in group C. CONCLUSION: The fortified cereal-legume laddoo may act as a novel vehicle for increasing calcium intake in children.