To our knowledge, this is the first study to examine 20-year changes in food consumption patterns among 2-6 year old children in the U.S. using nationally representative samples. Over a 20-year period, there is a marked increase in foods high in added sugars, solid fats and sodium in the preschooler diet. Per capita consumption of savory snacks, pizza/calzones, sweet snacks and candy, mixed Mexican dishes, and fruit juice, increased by a combined 148 kcal/day. In contrast, consumption of fruits from any source increased by only 24 kcal. Overall during this 20-year period, total daily energy intake increased by 109 kcal (from 1475 to 1584).
Our findings are compatible with increasing prevalence of overweight and obesity among young children across the same time period except for a recent leveling off (1
). Moreover, foods that tend to negatively impact diet quality, and contribute excess calories, such as savory and sweet snacks, pizza/calzones, mixed Mexican dishes, sweet snacks and candy, and fruit juice (40
), predominated the top changes in per capita consumption between 1989 and 2008.
Our results are consistent with other studies on diets of preschoolers during the last decade. Results from the Feeding Infants and Toddlers Study (FITS) showed that, on average, young children were consuming excessive amounts of saturated fats, higher than recommended amounts of salt, and too many calories from high-calorie, low-nutrient foods such as sweets, sweetened beverages, and french fries (17
). Furthermore, approximately 85% of children ages 2-3 consumed at least one serving of salty snack foods, sweetened beverages, desserts, or sweets on the survey day (18
). Recent data from the WWEIA, NHANES (2003-2004; 2005-2006) have yielded additional insight into the diets of young children. Reedy & Kreb-Smith (2010) reported that the top five sources of calories per capita, among 2-3 year olds, were whole milk, fruit juice, reduced-fat milk, and pasta and pasta dishes(23
). Among 4-8 year olds, the top five sources of calories were grain-based desserts, yeast breads, pasta, reduced-fat milk and pizza (23
). Fruit drinks, soda, grain desserts, dairy desserts and candy comprised the leading sources of added sugars, whereas whole milk, fatty meats, pizza, grain desserts and regular cheese were the leading sources of solid fats, among children ages 2-8 (23
The current research also echoes previous studies examining trends in dietary patterns among U.S. children. Others have shown reported sharp increases in snacking and caloric intake among U.S children across a similar time period (26
). Piernas and Popkin (2011) reported that salty snacks, which are included in the savory snacks food group, accounted for the greatest change in caloric intake between 1977 and 2006 among children ages 2-18 (26
). Nielsen et al (2002), who looked at dietary changes among 2-18 year olds, found that salty snacks, soft drinks and pizza underwent the largest increases in consumption among the foods examined between 1977 and 1996 (49
). Consumption of desserts, candy, soft drinks, fruit drinks and pizza also increased among 2-18 year olds during the same period(49
). Wang et al (2008) reported that per capita fruit juice consumption also increased in both 2-5 year old children, as well as among 6-11 year old children during the same period between 1988 and 2004 (50
). We also found that fruit consumption increased between 1989 and 2008, with a significant change occurring between 1989 and 1998, which is consistent with Kranz et al. (2004), who reported that total consumption of fruits increased in 2-5 year old U.S. children between 1977 and 1998 (51
Across surveys, there were minor differences in the distributions of race/ethnicity, to which some of the observed changed may be attributable. In Appendix Table 3, we compared changes in consumption between 1989-1991 and 2007-2008 by standardizing to the race/ethnicity distribution in the 1989-1991 survey. Adjusting for race/ethnicity had a marginal effect, which thereby suggests that differences in consumption among preschool children occurring between 1989 and 2008 are attributable mainly to factors other than race/ethnicity.
This study has several limitations. One is our use of surveys with different methods of dietary assessment. Starting in 1994, the USDA began using the multi-pass approach, which employs several steps to enhance the accuracy of recall (52
). Accordingly, prior survey years conducted without this method may be more prone to issues of recall bias. There is no bridging survey as there was in earlier decades to allow us to understand the impact of this methodological change(53
). These surveys, however, are the only ones which allow us to use consistent food composition tables, all developed by USDA to fit the food supply at the time of the survey.
Dietary data for each of the five surveys used was based on self-report, which may be prone to reporting bias and there is limited evidence that these reporting errors have increased over time, at least in Europe (54
). Moreover, subjects tend to underreport consumption of foods perceived to be unhealthy or related to obesity (54
). To the extent that these biases exist, our results reporting increases of food considered less healthful would represent a conservative assessment of these changes.
This study highlights an increase in the proportion of foods that are key sources of added sugars and solid fats and high in sodium in the diets of US preschool children in the past two decades. The large increases in savory snacks, pizzas, sweets, fruit juice and mixed Mexican dishes are patterns that are likely to affect future diets of these preschoolers as they age. The only positive change was a small increase in fruit intake. The dietary trends among US preschoolers reflected in this paper reinforce calls to improve the diets of young children in an effort to prevent obesity in children.