Tracking of dietary intake patterns is associated with baseline characteristics of urban low-income African-American adolescents

Young peoples' dietary habits may persist over time. However, few studies have examined the dynamic patterns in urban low-income African-American adolescents' intakes. This study examined these dynamic patterns and their predictors and explored the association between the patterns and BMI over time. Dietary data were collected from 181 low-income African-American adolescents using a 152-item FFQ at baseline and 1-y follow-up. High intakes and high BMI were defined as the top quartile and high-fat intake as >35% of energy from fat. Multinomial logistic regression models were fit to study the association between study variables. Correlation coefficients (0.4 < r < 0.6; P< 0.05) between participants' intakes at baseline and at 1-y follow-up suggested tracking, particularly intakes of energy, fat, fiber, calcium, vegetables and fruits, fried food, and snack food. However, the tracking of percentage of energy from fat and sugar-sweetened beverages was weak (0.2 <= r < 0.3; P < 0.01). Proportion of agreement (>30%) and k-values (>0.2) also indicated tracking. Adjustment for tracking of energy changed little the observed tracking for other micronutrients and food groups. Factor analysis showed moderate tracking in a Western diet pattern (r= 0.47; P < 0.001) but was weaker in 2 healthier diet patterns (r= 0.31-0.36; P < 0.001). Age, gender, physical activity, and BMI predicted dietary changes (P < 0.05). Adolescents who tracked high intakes of energy, fiber, fried food, and snacks were less likely to track high BMI. Decreased energy and snack intakes were negatively related to tracking of high BM I. Overall, urban low-income African-American adolescents tracked their dietary patterns over time. The tracking was affected by baseline characteristics.