A study of U.S. insurance claims has found that 16.8% of children and adolescents who started a GLP-1 receptor agonist received a diagnosis of at least one nutritional deficiency or related complication within a year. The finding raises questions about nutrition monitoring as use of the drugs grows among young people being treated for obesity or diabetes.
But the study, published in Childhood Obesity, cannot show that GLP-1 medicines caused the diagnoses. It tracked billing claims after treatment began in a group of 2,031 patients ages 10 to 17, without a reported comparison group of similar children who did not receive the drugs. Claims also record diagnoses and billed services, rather than systematically measured diets or laboratory results.
What the study measured
Researchers examined national administrative claims from 2017 through 2022, drawing from a database that covers more than 100 million patients. The analysis included 2,031 young people who had a GLP-1 prescription, continuous insurance enrollment and no previously recorded diagnosis of nutritional deficiency. An account from Northwestern University and Lurie Children’s Hospital, where researchers involved in the work are based, describes the study as an effort to examine diagnosed deficiencies and nutrition-care use after treatment started.
The headline figure needs some precision. The 16.8% rate represents patients with at least one diagnosis of a nutritional deficiency or related complication during the year after their first prescription; it is not a measure of laboratory-confirmed deficiencies alone. At 180 days, the corresponding composite rate was 10.2%.
Vitamin D deficiency was the most frequently recorded individual diagnosis, appearing in 12.4% of the cohort within a year. Vitamin D, iron and calcium are among nutrients that are important during adolescence, a period of rapid growth and bone development. The claims analysis, however, does not establish whether patients had inadequate intake, whether they had been screened more intensively after beginning medication, or whether a diagnosis reflected a condition that was present but unrecognized before treatment.
The medication mix also limits how directly the results can be applied to current prescribing. Liraglutide accounted for 78.6% of prescriptions in the study population, compared with 10.4% for dulaglutide and 9.1% for semaglutide. The data period came before semaglutide became widely used among adolescents, meaning the results chiefly reflect an earlier treatment landscape.
Why the findings do not prove medication harm
GLP-1 receptor agonists can reduce appetite and food intake, making nutritional follow-up a plausible clinical concern. Yet a temporal pattern in insurance records is not a causal estimate. The available description of the study does not report randomized treatment assignment, a matched untreated comparison group or an analysis that separates medication effects from factors such as underlying obesity or diabetes, baseline diet, socioeconomic conditions and differences in access to care.
Independent coverage has similarly noted the observational design and its inability to determine whether the drugs themselves led to later diagnoses. Gizmodo’s report on the study highlighted that the results show an association in this treated group, not proof of cause and effect.
There are two directions of uncertainty in claims data. Conditions that were never tested for or diagnosed will not appear, so the records may understate subclinical or untreated deficiencies. At the same time, a claims diagnosis is not equivalent to a standardized laboratory screening result for every participant. The database cannot provide direct information on food intake, supplement use, medication adherence, clinical severity or care that was not billed through the captured insurance system.
The study was funded by Abbott. Funding does not determine a study’s result, but it is relevant context when assessing research on clinical care and should be considered alongside the design limitations and the need for replication in more current patient populations.
Low recorded use of nutrition counseling
The researchers also examined use of nutrition therapy or counseling. Just 5% of patients had a billed counseling service within 30 days of beginning a GLP-1 medicine. Fewer than one-quarter did so within six months; Nutrition Insight’s coverage put the six-month figure at 23.3%.
Those numbers should not be read as a complete count of nutrition support. Families may have received dietary guidance during medical appointments without a separately coded counseling claim, paid out of pocket, or obtained services outside the insurance records used for the analysis. Still, the low documented rate points to a potential gap between prescribing and formally recorded nutrition care.
For clinicians, the findings support attention to nutritional assessment and counseling when GLP-1 medicines are used in adolescents, especially because growth and pubertal development continue through the age range studied. They do not provide a basis for patients or families to stop prescribed treatment on their own. A clearer estimate of medication-related risk would require studies that compare similar treated and untreated young people, use direct laboratory and dietary data, and reflect today’s broader use of semaglutide.