The impact of nutritional policy on socioeconomic disparity in the unhealthy food intake among Korean adolescents

The objectives of this study were to examine the trend in unhealthy food intake by socioeconomic position (SEP) and to determine whether the government's nutritional policies affect socioeconomic disparity in the food intake among adolescents. Data were from the six independent cross-sectional survey data (2006-2011) of Korea Youth Risk Behavior Web-based Survey and included 445,287 subjects aged 12-18 years. The unhealthy food intake was assessed by food frequency intake and SEP was evaluated with the family affluence scale. We observed that unhealthy food intakes decreased through the years, showing the apparent decline when nutritional policies focusing on the restriction of unhealthy foods were implemented, and the trend was all same in the different SEP groups. The pattern of unhealthy food intakes by SEP has changed before and after implementation of the policies. The intakes of carbonated beverages, fast food, and confectioneries were higher in the higher SEP group before implementation of the policies but the difference was not shown after implementation of the policies. The intake of instant noodles was consistently higher in the lower SEP group. The risk of frequent consumption of unhealthy foods was generally more decreased through the years in the higher SEP group than the lower SEP group. In conclusion, this study found the positive effect of nutritional policy on unhealthy food intake among adolescents and the high SEP group appeared to undergo greater desirable changes in dietary behaviors after implementation of nutritional policies than the low SEP group.