Just under 17% of 10- to 17-year-olds who started a GLP-1 drug were diagnosed with a nutritional deficiency or a related complication within the following year, an analysis of US insurance claims has found. Most of those diagnoses were vitamin D deficiency. Fewer than a quarter of the teenagers saw anyone for nutrition counselling within six months of starting. The study, published on 17 September in Childhood Obesity, was written largely by employees of Abbott Nutrition, which sells nutritional products — a conflict worth carrying through the rest of the reading.
What the records show
The authors drew on Inovalon administrative claims covering more than 100 million patients between 2017 and 2022, and identified 2,031 patients aged 10 to 17 who started a GLP-1 receptor agonist, remained continuously enrolled, and had no nutritional-deficiency diagnosis beforehand. They then looked for ICD-10 deficiency codes in the year after the first prescription.
The cohort averaged 15 years old, was 61.5% female, and 62.6% carried an obesity diagnosis. The drugs were largely older ones: liraglutide accounted for 78.6% of prescriptions, dulaglutide 10.4% and semaglutide 9.1% — a reminder that this is a 2017–2022 picture, taken before the current prescribing mix.
Within a year, 16.88% had at least one nutritional deficiency or deficiency-related complication recorded. Vitamin D deficiency accounted for most of that at 12.4%, followed by nutritional anaemia at 1.55% and iron-deficiency anaemia at 1.44%. On the care side, only 23.3% had a nutrition therapy or counselling visit within 180 days, and the mean time to a first such visit was 149 days. One result runs against the paper’s framing: teenagers who did receive nutrition counselling had more deficiency diagnoses recorded, not fewer, at 23.2% against 14.8%.
Reading the counselling result carefully
That last finding is the one to slow down on. The authors present the overall picture as missed opportunities for proactive nutrition support, and the low counselling rate is a fair thing to flag. But the direction of the counselling comparison is most plausibly confounding by indication: a teenager is referred to a dietitian because something has already surfaced — poor intake, weight loss that worries the clinician, an abnormal laboratory result — so referral marks a higher-risk group rather than causing the deficiencies. The study is observational and does not attempt to separate those explanations.
The vitamin D figure deserves matching caution in the other direction. Vitamin D deficiency is common in adolescents generally, and more common in those with obesity; it is also a test ordered more often once a young person is under active metabolic care. Some of that 12.4% is likely detection — a deficiency that already existed and was found — rather than anything treatment produced. Without a comparison group of similar teenagers not taking these drugs, the study cannot distinguish the two.
That missing comparison group is the central limitation: there are no matched adolescents with obesity who did not start a GLP-1 drug, so the paper cannot say whether 16.88% is above the background rate, which is the question a parent would actually ask. The prescribing mix is dated and dominated by liraglutide. Claims capture diagnoses rather than measured nutrient levels, so anything never tested for is invisible. And five of the six authors work for Abbott, which sells oral nutritional supplements; that does not make the counts wrong, but it does place the paper’s conclusion close to a product.
Sources: Kerr KW, Chang AT, Sulo S, Stutts JT, Panchalingam T, Ryder JR. “Nutritional Deficiencies, Complications, and Nutrition Therapy/Counseling in Pediatric Patients Using GLP-1 Receptor Agonists.” Childhood Obesity, published online 17 September 2026 (doi:10.1177/21532176261486979).
