Dairy intake is associated with lower body fat and soda intake with greater weight in adolescent girls

Abstract

Body fat and weight of 9- to 14-y-old girls (n = 323) from Kaiser Permanente were studied in relation to age, ethnicity, and physical activity. Mean age, calcium intake, weight, and iliac skinfold thickness were 11.5 ± 1.4 y, 736.5 ± 370.7 mg/d, 44.6 ± 13.0 kg, and 12.4 ± 6.1 mm, respectively. Multiple regression with age, ethnicity, height, Tanner breast stage, physical activity, energy, soda, and calcium intake explained 17% of the variation in iliac skinfold thickness. Calcium intake, age, and physical activity were significantly negatively associated with iliac skinfold thickness whereas height, Tanner breast stage, and Pacific Islander ethnicity were significantly positively associated (P < 0.0001, R2 = 0.165). Substituting total calcium with dairy and nondairy calcium in separate models accounted for 16 and 15% of the variance, respectively (P < 0.0001, both models); 1 mg of total and dairy calcium was significantly associated with 0.0025 mm (P = 0.01) and 0.0026 mm (P = 0.02) lower iliac skinfold thickness. Thus, 1 milk serving was associated with 0.78 mm iliac skinfold thickness. The interaction of Asian ethnicity and dairy intake was significant (P = 0.027). Nondairy calcium was not associated with weight or iliac skinfold thickness. Soda intake was significantly positively associated with weight in both models (P = 0.01, both models). Decreasing soda and increasing dairy consumption among Asians may help maintain body fat and weight during adolescence.