Snacking is associated with weight status in adolescents; adolescents with obesity consume more frequent and larger snacks compared to adolescents with normal weight. However, the relationship between snacking and overall diet quality in adolescents in unclear. The purpose of this study was to examine multiple parameters of snacking and their association with diet quality among U.S. adolescents.


Participants were 7,010 adolescents aged 12-19 years, participating in the 2005-2016 National Health and Nutrition Examination Survey (NHANES). Snack frequency, snack size, snack energy density, and snack-to-meal size ratio were estimated using the mean of two 24-hr dietary recalls. Diet quality was estimated using the 2015 Healthy Eating Index (HEI). The 2015-HEI includes 13 components of dietary intake (e.g., total fruit intake, total vegetable intake) and results in a sum score ranging from 0-100, with 0 representing the lowest and 100 representing the highest diet quality. Linear regression models examined each snacking parameter as a predictor of total HEI, adjusting for all other snacking parameters along with demographic characteristics and estimated energy reporting accuracy.


Adolescents were 15.4 (0.05) years, 50.2% female, 34.6% Hispanic, 27.5% white, 27.6% black and had a mean HEI of 45.0 (0.26). Mean number of daily snacks was positively associated with HEI (β(SE)=0.56 (0.26), p=0.038). Mean snack size and snack-to-meal ratio were inversely associated with HEI (β(SE)= -0.005 (0.001), p<0.001; β(SE)=-1.18 (0.53), p=0.028). Snack energy density was not associated with HEI (β(SE)=-0.29 (0.23), p=0.208).


Overall, adolescents have sub-optimal diet quality, but smaller, more frequent snacks are associated with higher diet quality. A higher ratio of calories from snacks compared to meals was associated with poorer diet quality. Longitudinal and experimental data are needed to better understand the causal role of snacking in diet quality during adolescence.