The association of fluoride in drinking water with serum calcium, vitamin D and parathyroid hormone in pregnant women and newborn infants.

BACKGROUND: Chronic exposure to fluoride in drinking water causes an increase in plasma fluoride levels that is related to a reduction in calcium transport across the renal tubule endoplasmic reticulum and plasma membrane. In the present study, it was hypothesised that varying levels of fluoride present in drinking water are associated with serum levels of calcium and the related hormones vitamin D and parathyroid hormone in pregnant women and newborn infants. METHODS: This cross-sectional study included two groups based on the fluoride concentration in drinking water. One group was considered low/optimum in which the fluoride concentration in drinking water was <1 ppm, and the other group was considered a high fluoride group with ≥1 ppm fluoride in drinking water. In each group, 90 pregnant women were recruited at the hospital during delivery. The participants were given a questionnaire regarding their medical history, sunshine exposure duration, and supplement use and a food frequency questionnaire (FFQ). Fluoride was measured in drinking water, urine, maternal serum and cord blood. Serum calcium, vitamin D, and parathyroid hormone were measured in a fully automated analyser. RESULTS: In pregnant women, drinking water that contained fluoride was significantly positively correlated with urine and blood serum. Low mean concentrations of vitamin D and deficient (<10 ng/ml) vitamin D were more prevalent among the high fluoride group irrespective of diet, sunshine exposure and supplementation. Serum calcium and parathyroid hormone (PTH) levels were significantly lower in the high fluoride group than in the low/optimum fluoride group in both pregnant mothers' blood and cord blood. CONCLUSIONS: Drinking water with high fluoride levels was significantly associated with calcium and the related hormones vitamin D and parathyroid hormone.

Chronic sub-clinical inflammation in the abdominal adipose tissue - Evaluation of inflammatory cytokines and their link with insulin resistance in metabolically obese South Indians: A cross-sectional observational study.

OBJECTIVE: To measure the levels of proinflammatory cytokines tumor necrosis factor-alpha (TNF-α), interleukin-6(IL-6), and high-sensitive C-reactive protein (hs-CRP) and the anti-inflammatory cytokine adiponectin (AN) in obese South Indian subjects and to ascertain whether or not a causal role could be ascribed to these cytokines in the development of insulin resistance (IR). MATERIALS AND METHODS: Forty obese and forty nonobese volunteers of both genders were recruited. Parameters such as body mass index (BMI), waist circumference (WC), and blood pressure were evaluated. Fasting blood sugar (FBS), fasting insulin level, hemoglobin A1c (HbA1C), lipid profile, TNF-α, IL-6, hs-CRP, and AN levels were measured. IR was evaluated by homeostatic model assessment-IR method. Abdominal adiposity was measured by ultrasonography. The results were statistically evaluated by appropriate tests. RESULTS: BMI, WC, and visceral fat were high in the obese group. Females had higher subcutaneous fat in both groups. HbA1C was marginally high in the obese group (P = 0.014). IR was high in all the groups, obese males showing higher values (not significant[NS]). Total cholesterol and low-density lipoprotein were high in the obese group (P = 0.028, P = 0.003). TNF-α was high in obese males (NS), IL-6 was high in both groups, higher in nonobese females (NS), hs-CRP was high in both groups, higher in females of both groups (NS). AN was high in females of both groups (P = 0.002). CONCLUSIONS: In this study on South Indian subjects, proinflammatory cytokines such as IL-6 and hs-CRP, despite being high, did not show any causal correlation either with abdominal obesity or with IR. TNF-α being normal showed some correlation which was inconsistent. Even the anti-inflammatory adipokine, AN did not show any correlation with IR. Cytokines had an inconsistent correlation with the components of metabolic syndrome hence were not useful.