New Johns Hopkins research highlights success of digital tools in curbing childhood obesity

A recent study led by researchers at Johns Hopkins Children’s Center, in collaboration with several academic institutions, suggests that integrating digital feedback with traditional in-clinic counselling for parents could help prevent obesity in young children who are at high risk. By using text messaging and digital tools to reinforce advice on nutrition, activity, and play, the study indicates a significant potential for curbing childhood obesity and related long-term health risks.

The research, co-led by Eliana Perrin, M.D., M.P.H., Bloomberg Distinguished Professor of Primary Care at the Johns Hopkins University Schools of Medicine, Nursing, and Public Health, will be published in the Journal of the American Medical Association (JAMA) and presented at the Obesity Society’s “Obesity Week” conference in San Antonio. This study builds on decades of research highlighting the increased risk of lifelong obesity, cardiovascular disease, diabetes, and other serious conditions for young children with obesity, particularly within low-income and minority groups.

According to data from the U.S. Centers for Disease Control and Prevention (CDC), approximately 1 in 5 school-aged children had obesity in 2017–18, a figure that has only grown due to the COVID-19 pandemic. Efforts to lower these rates have often focused on in-person counselling, which has had limited success. In response, the Johns Hopkins team developed a new digital approach to support the Greenlight Program, an intervention designed by Perrin and colleagues that previously relied solely on written materials and in-person counselling during paediatric visits.

Building on prior knowledge, Perrin noted, “We found that parents are eager for more information to help their children grow up healthy, and the vast majority of parents own smartphones.” With this in mind, the researchers expanded the Greenlight Program to incorporate digital messaging, with the goal of sustaining healthier behaviours as paediatric visits become less frequent after age two.

In collaboration with Vanderbilt University and five other institutions, the research team recruited nearly 900 parent-infant pairs from medical centres including Duke University, University of Miami, New York University/Bellevue Hospital Centre, University of North Carolina, Stanford University, and Vanderbilt University Medical Centre. The study began with infants aged 21 days or younger who were born after 34 weeks, at a healthy weight, and had no chronic medical conditions that might influence weight gain.

Approximately 45% of the participants identified as Hispanic, 20% as white, and nearly 16% as Black, with over half experiencing low health literacy and nearly 16% facing food insecurity. To assess the intervention’s effectiveness, parent-infant pairs were randomly assigned into two groups. Both groups received Greenlight Program materials, which included age-appropriate booklets and in-person counselling from primary care providers about nutrition, physical activity, sleep, and screen time.

Half of the group, however, received an additional digital intervention: a system of interactive text messages sent every two weeks in English or Spanish to support health behaviour goals such as reducing sugary drinks or minimising screen time. These messages were personalised and linked to a web-based “dashboard” where parents could track progress and self-rate their goal achievements. Depending on parents’ feedback, the digital system provided immediate suggestions, motivational tips, and reminders to reinforce health behaviours.

Results from the study reveal that children whose parents received digital feedback, along with in-person counselling, showed healthier weight-for-length growth curves over the first two years of life compared to those who received only in-clinic counselling. At the two-year mark, children in the digital group had a reduction in weight-for-length ratio of 0.33 kg/m, an amount researchers deemed meaningful for effective obesity prevention. Moreover, the prevalence of obesity was notably lower in the digital intervention group, with around 7% of children developing obesity compared to 13% in the clinic-only group, representing an adjusted relative reduction of nearly 45%.

The digital approach proved especially beneficial in populations with the highest risk factors for obesity. “The digital services could have significant impact if implemented on a broader scale,” the researchers noted, as the intervention’s effect was observed as early as 4 months and remained consistent throughout the two-year study period.

Dr Perrin highlighted the importance of these findings, noting, “Most young children with obesity do not outgrow it. What is exciting from our study is that we prevented those children who would have had an unhealthy weight from the outset, helping them to achieve a healthier weight that can support lifelong health.”

The study also found that the digital intervention was particularly effective among children from food-insecure households, Hispanic and non-Hispanic Black children, and those with limited health literacy. Perrin underscored the potential of this programme in reducing health disparities, stating, “If we can prevent obesity in these children at greatest risk, we can also create better health equity in the future.”

The research team hopes to track the participants’ health outcomes as they grow, aiming to gather more data on the long-term impacts of early obesity prevention through digital intervention.

Additional contributors to the study include William Heerman, Russell Rothman, Jonathan Schildcrout, Aihua Bian, Laura Adams, and Evan Sommer from Vanderbilt University Medical Centre; Lee Sanders from Stanford University; Kori Flower from the University of North Carolina at Chapel Hill; Alan Delamater from the University of Miami; Melissa Kay from Wake Forest University; Charles Wood from Duke University; Rachel Gross and H. Shonna Yin from New York University; along with other Greenlight investigators.