Bone Abstracts

Objective: Low dietary calcium intakes and increasing adiposity in Indian adolescents may increase their risk of hypertension (Sanwalka et al., Asia Pac J Clin Nutr. 2010, Khadilkar et al., Int J Pediatr Obes. 2010). Therefore, the aim of the present study was to explore association of dietary calcium intakes and body composition with blood pressure in 10–14 year old Indian adolescents.

Method: 370 apparently healthy adolescents (190 boys) with mean age 12.1±1.3 years were studied from five major Indian cities. Anthropometry (height, weight, BMI, waist circumference), blood pressure (BP-mercury sphygmomanometer), BIA–(Body composition analyser-Tanita-SC-240, %fat, muscle mass) and 24 h-Diet recall (C-diet, V2.0) were recorded using standard protocols (data addition ongoing).

Results: Subjects were divided into sub groups as with normal BP, pre-hypertension and hypertension using height & gender matched Indian reference data (Raj et al., Indian Paediatrics, 2010). Hypertension was found in 6% boys and 4% girls. Subjects with pre-hypertension and hypertension had significantly higher weight and BMI z-scores, waist & fat % (P<0.05). Dietary calcium intakes were significantly lower in the group with hypertension (P<0.05). Majority of the subjects (80%) from higher BP groups had daily calcium intakes below RDA than normal BP subjects (58%). Other nutrient intakes were similar among all the three groups (P>0.1). Dietary calcium intake was negatively correlated with BP (systolic and diastolic) (r=−0.240, P<0.0001) even after adjusting for energy intake. Further, BP was also positively correlated with BMI (r=0.54), waist (r=0.52) and body fat% (r=0.56) (P<0.001). Generalised linear model analysis revealed that dietary calcium, body fat % and waist were significantly associated with blood pressure (P<0.01) even after adjustment for height.

Conclusion: Low dietary calcium intakes and high adiposity increase the risk of hypertension in Indian adolescents.

Disclosure: The authors declared no competing interests.