The average American child's diet improved considerably from 1999 to 2016, with less soda and more fruits and vegetables, though unhealthy diets remained the rule rather than the exception, researchers reported.
Analysis of National Health and Nutrition Examination Survey (NHANES) data on more than 30,000 young people over the 18-year span indicated that the proportion with poor diets declined from 76.8% to 56.1% (P<0.001), according to Junxiu Liu, PhD, of Tufts University in Boston, and colleagues.
As shown in their study online in , the proportion of youth with an intermediate dietary score increased significantly during that time period, from 23.2% to 43.7% (P<0.001). The percentage of young people with an ideal dietary score, however, remained low, increasing from just 0.07% to 0.25% (P=0.03), Liu's team said.
Consumption of sugar-sweetened beverages decreased from a mean of two servings a day to just one (difference -1.0, 95% CI -1.2 to -0.78), and added sugar consumption decreased from 106 g to 71.4 g a day (difference -34.4, 95% CI -40.8 to -28.1; P<0.001 for both).
Mean consumption of whole grains significantly increased from 0.46 to 0.95 servings per day (difference +0.50, 95% CI 0.40-0.59), and consumption of total fruits and vegetables increased from 1.62 to 1.81 daily servings (difference +0.19, 95% CI 0.06-0.32; P<0.001 for both), the study found.
"From 1999 to 2016, overall dietary quality improved among U.S. youth, associated with increased consumption of fruits and vegetables (especially whole fruits) and whole grains, with additional increases in total dairy, total protein foods, seafood, and plant proteins, and decreased consumption of sugar-sweetened beverages and added sugar," Liu and colleagues wrote.
The diets did not improve in one important area, however: sodium consumption increased from a mean of 3,166 mg to 3,326 mg per day (P<0.001), far exceeding the 2019 National Academies of Sciences, Engineering, and Medicine dietary reference intake of 2,300 mg per day.
The increase "may relate to steadily increasing consumption of processed foods and food prepared away from home," the researchers speculated. "These findings support the need for reactivating the currently suspended long-term U.S. Food and Drug Administration voluntary sodium targets and timelines for reducing sodium in packaged foods and restaurant foods."
Asked for her perspective, Lauri Wright, PhD, of the University of North Florida in Jacksonville, who was not involved with the study, said: "I believe this study is good news, showing improvements in youth's eating patterns. There might be many things at play here. One might be the impact of the changes in the school lunch program in 2012 (with many changes occurring prior). The reformed school lunches were much higher in fruit and vegetables, lean dairy, nuts, and whole grains, while lower in fat and sodium."
In addition, she told via email, there has been more education directed at kids and parents about eating healthier. For example, she said, programs such as significantly improved the amount of positive nutrition messaging.
"Finally, I feel there are many more 'healthy' products out there for kids and parents to choose from," Wright said. "Water and low-fat dairy have become the norm over the once popular sugar-sweetened beverages. Though the study shows we still have a ways to go in improving youth's eating patterns, it does show the impact policy and education can have."
For the study, Liu and colleagues analyzed data across nine NHANES cycles, from 1999-2000 through 2015-2016. The study included young people ages 2 to 19 who had completed at least one valid 24-hour dietary recall. A total of 31,420 youth were included. Their mean age was 10.6, and 49% were female. Respondents reported all food and beverages consumed during the past 24 hours, midnight to midnight. For younger children, proxy-assisted interviews were conducted.
Diet quality was determined by the 50-point American Heart Association (AHA) 2020 continuous diet score. Poor diet was defined as a score of less than 20, an intermediate diet was 20 to 39.9, and an ideal diet was 40 or higher. The researchers also assessed youth diets with the 100-point , and the results were similar.
Additional study findings included the following:
- Whole fruit intake increased from 0.46 to 0.68 daily servings, while 100% fruit juice intake decreased from 0.63 to 0.46 servings (P<0.001 for both)
- Unprocessed red meat consumption decreased from 0.35 to 0.31 daily servings (P=0.01), while processed meat consumption remained stable
- Carbohydrate consumption decreased from 55.4% to 51.9% of total energy intake (P<0.001)
- Total fat intake increased from 33.2% to 34.5% of energy, and dietary cholesterol increased from 218 to 254 mg per day (P<0.001 for both)
- Fiber intake increased from a mean of 12.4 mg to 15.6 mg per day (P<0.001)
Finally, diets tended to worsen as children got older, reflecting the greater amount of unhealthy choices available to older children. as well as the increased freedom to choose them, Liu and colleagues said. For example, in 2016 the estimated proportion of children ages 2-5 having a poor diet was 39.8%. That percentage rose to 52.5% for children ages 6-11 and to 66.6% for those ages 12-19.
Limitations of the study, the researchers said, included the inaccuracies associated with self-reported dietary recall, as well as the cross-sectional nature of the analysis, which did not allow for evaluating dietary changes among individuals, only of national trends.
Disclosures
The study was supported by the National Institutes of Health and the American Heart Association.
Liu reported no conflicts of interest; co-authors disclosed relationships with the National Dairy Council, PepsiCo, General Mills, and other companies and organizations.
Wright reported no conflicts of interest.
Primary Source
JAMA
Liu J, et al "Trends in diet quality among youth in the United States, 1999-2016" JAMA 2020; 323(12): 1161-1174.