The relationship between dietary calcium intake and body composition in adolescents

Abstract

Objective To examine the association between dietary calcium intake and measures of body composition in adolescents. Methods Adolescents (n=91), attending an urban Adolescent Medicine clinic, were recruited to participate. Using a cross-sectional design, body mass index, skinfold thicknesses (4 sites), natural and navel waist circumferences, and dietary intake via 24 hour dietary recalls were obtained by a trained technician. Percent body fat was calculated using the equations of Durnin and Passmore. Dietary data was analyzed with Food Processor™ (Esha Research), and a calcium/kcalorie ratio was calculated to account for underreporting. Spearman correlation analysis was used to explore the relationships in the data. Results Mean age for the subjects was 15 ± 2 years. Mean total kcalorie intake, calcium intake, and calcium/kcalorie ratio were 1907 ± 1004 kcal/d, 644 ± 584 gm/d, and 0.33 ± 0.2 respectively. Mean BMI (kg/m2), % body fat, and natural and navel waists (cm) were 26.2 ± 7.1, 32.9 ± 7.9, 80.7 ± 14.6, 82 ± 16.6. There was a significant relationship between calcium/kcalorie ratio and percent body fat (r = 0.22, p < 0.05). There were no significant relationships between total calcium, total kcalories, or frequency of calcium consumption and percent body fat, waist circumference measures, or BMI. Conclusion In contrast to previous reports, our results suggest a positive relationship between calcium intake and percent body fat,. To adjust for underreporting, we divided calcium intake by kcalories. This may not have been sufficient to overcome underreporting by adolescents.