In the 2 decades from 1999 to 2018, ultraprocessed foods consistently accounted for the majority of energy intake by American young people, a large cross-sectional study of National Health and Nutrition Examination Survey (NHANES) data shows.
In young people aged 2-19 years, the estimated percentage of total energy from consumption of ultraprocessed foods increased from 61.4% to 67.0%, for a difference of 5.6% (95% confidence interval [CI] 3.5-7.7, P < .001 for trend), according to Lu Wang, PhD, MPH, a postdoctoral fellow at the Friedman School of Nutrition Science and Policy at Tufts University in Boston, and colleagues.
In contrast, total energy from non- or minimally processed foods decreased from 28.8% to 23.5% (difference −5.3%, 95% CI, −7.5 to −3.2, P < .001 for trend).
“The estimated percentage of energy consumed from ultraprocessed foods increased from 1999 to 2018, with an increasing trend in ready-to-heat and -eat mixed dishes and a decreasing trend in sugar-sweetened beverages,” the authors wrote. The report was published online Aug. 10 in JAMA.
The findings held regardless of the educational and socioeconomic status of the children’s parents.
Significant disparities by race and ethnicity emerged, however, with the ultraprocessed food phenomenon more marked in non-Hispanic Black youths and Mexican-American youths than in their non-Hispanic White counterparts. “Targeted marketing of junk foods toward racial/ethnic minority youths may partly contribute to such differences,” the authors wrote. “However, persistently lower consumption of ultraprocessed foods among Mexican-American youths may reflect more home cooking among Hispanic families.”
Among non-Hispanic Black youths consumption rose from 62.2% to 72.5% (difference 10.3%, 95% CI, 6.8-13.8) and among Mexican-American youths from 55.8% to 63.5% (difference 7.6%, 95% CI, 4.4-10.9). In non-Hispanic White youths intake rose from 63.4% to 68.6% (difference 5.2%, 95% CI, 2.1-8.3, P = .04 for trends).
In addition, a higher consumption of ultraprocessed foods among school-aged youths than among preschool children aged 2-5 years may reflect increased marketing, availability, and selection of ultraprocessed foods for older youths, the authors noted.
Food processing, with its potential adverse effects, may need to be considered as a food dimension in addition to nutrients and food groups in future dietary recommendations and food policies, they added.
“An increasing number of studies are showing a link between ultraprocessed food consumption and adverse health outcomes in children,” corresponding author Fang Fang Zhang, MD, PhD, Neely Family Professor and associate professor at Tufts’ Friedman School of Nutrition Science and Policy, said in an interview. “Health care providers can play a larger role in encouraging patients – and their parents – to replace unhealthy ultraprocessed foods such as ultraprocessed sweet bakery products with healthy unprocessed or minimally processed foods in their diet such as less processed whole grains. “
In Dr. Zhang’s view, teachers also have a part to play in promoting nutrition literacy. “Schools can play an important role in empowering children with knowledge and skills to make healthy food choices,” she said. “Nutrition literacy should be an integral part of the health education curriculum in all K-12 schools.”
Commenting on the study but not involved in it, Michelle Katzow, MD, a pediatrician/obesity medicine specialist and assistant professor at the Feinstein Institutes for Medical Research in Manhasset, N.Y., said the work highlights an often overlooked aspect of the modern American diet that may well be contributing to poor health outcomes in young people.
“It suggests that even as the science advances and we learn more about the adverse health effects of ultraprocessed foods, public health efforts to improve nutrition and food quality in children have not been successful,” she said in an interview. “This is because it is so hard for public health advocates to compete with the food industry, which stands to really benefit financially from hooking kids on processed foods that are not good for their health.”
Dr. Katzow added that the observed racial/ethnic disparities are not surprising in light of a growing body of evidence that racism exists in food marketing. “We need to put forward policies that regulate the food industry, particularly in relation to its most susceptible targets, our kids.”