مواجهه با تبلیغات مواد غذایی در تلویزیون : در ارتباط با فست فود کودکان و مصرف نوشابه و چاقی

There is insufficient research on the direct effects of food advertising on children's diet and diet-related health, particularly in non-experimental settings. We employ a nationally-representative sample from the Early Childhood Longitudinal Survey–Kindergarten Cohort (ECLS-K) and the Nielsen Company data on spot television advertising of cereals, fast food restaurants and soft drinks to children across the top 55 designated-market areas to estimate the relation between exposure to food advertising on television and children's food consumption and body weight. Our results suggest that soft drink and fast food television advertising is associated with increased consumption of soft drinks and fast food among elementary school children (Grade 5). Exposure to 100 incremental TV ads for sugar-sweetened carbonated soft drinks during 2002–2004 was associated with a 9.4% rise in children's consumption of soft drinks in 2004. The same increase in exposure to fast food advertising was associated with a 1.1% rise in children's consumption of fast food. There was no detectable link between advertising exposure and average body weight, but fast food advertising was significantly associated with body mass index for overweight and obese children (≥85th BMI percentile), revealing detectable effects for a vulnerable group of children. Exposure to advertising for calorie-dense nutrient-poor foods may increase overall consumption of unhealthy food categories.

Public health experts increasingly call for substantial changes in the food environment to effectively address the epidemic of obesity and poor diet among young people (Frieden et al., 2010, Goldberg and Gunasti, 2007 and Story et al., 2008). Many consider the volume of marketing for calorie-dense nutrient-poor foods targeted to children and adolescents to be one of the most pernicious environmental influences on food consumption by youth (Harris et al., 2009a and Swinburn et al., 2008). A recent White House Task Force on Childhood Obesity Report to the President highlights the need for additional research to establish the link between advertising and “food preferences and consumption by children and adolescents” (White House Task Force on Childhood Obesity, 2010). A substantial body of literature consistently demonstrates that food marketing increases children's preferences, requests to parents and choices of advertised brands; however, far fewer studies have examined effects of food marketing on consumption of food categories (Hastings et al., 2003 and Institute of Medicine, 2006). Recent research provides indirect evidence that food marketing can have a significant impact on unhealthy food consumption in children in the short-term (Epstein et al., 2008, Halford et al., 2004, Halford et al., 2007 and Harris et al., 2009b). There is also evidence of long-term effects: television exposure in middle and high school predicts increased consumption of foods commonly advertised to youth five years later (Barr-Anderson et al., 2009). One study found that adiposity in children increased with exposure to fast food advertising and that banning those advertising practices could reduce the incidence of childhood overweight by 18% (Chou et al., 2008). This is true even though descriptive studies show that exposure to food advertising by children and adolescents has remained stable and may even slightly declined (Desrochers and Holt, 2007, Holt et al., 2007 and Zywicki et al., 2004). Yet “Holt et al. (2007) do not directly address the postulated link between ad exposure and food consumption or other behaviors that may be related to obesity” (Desrochers and Holt, 2007, p. 198), which we explore in the current analysis. They also do not account for a host of other factors occurring simultaneously in the time period that may be affecting both changes in advertising and obesity.

We observed higher consumption of soft drinks and fast food in children with increased exposure to TV advertising for CSDs and fast food. These findings suggest that children's exposure to advertising for calorie-dense nutrient-poor foods is associated with increased overall consumption of the unhealthy food categories commonly advertised to children. This may contribute to poor diet in children in the short-term, with potential long-term effects on BMI and health, especially among the heaviest children. Additionally, we found an association between CSD advertising and soft drink consumption regardless of whether we used advertising measures for sugar-sweetened or diet products or their combination. Recently, beverage companies have increased advertising of their diet products relative to sugar-sweetened products (Harris et al., 2010a), yet our results suggest it does not matter. Lack of association in models testing the specification (e.g., cereal advertising as a predictor of soft drink and fast food consumption) also helps rule out potential spurious correlation. The association between exposure to TV food advertising and children's body weight is mainly confined to the upper tail of the BMI distribution. Increasing exposure to fast food advertising on TV is strongly associated with higher BMI z-scores among 5th graders in the upper tails of the BMI distribution starting at the 75th percentile. The opposite is true for exposure to cereal advertising, although the negative BMI association may be explained by breakfast eating behaviors. Cereal consumption predicts the probability that a child eats breakfast ( Albertson et al., 2003 and Nicklas et al., 1994), and consuming breakfast is associated with good health (Siega-Riz et al., 1998).