A glass of milk, from NIAID's public health image library
NIAIDCC BY 2.0
Illustrative. Not a photo of any participant in the study, and not a claim that milk alone resolves the deficiencies described.
Nearly 1 in 6 Teens on GLP1 Drugs Developed a Nutritional Deficiency, and Almost None Got Counseling
GLP1 prescribing in teenagers is climbing fast, and most of the public conversation about that is focused on weight loss numbers and safety headlines. A new study asks a quieter, more practical question: once a teenager starts one of these drugs, is anyone actually checking whether they are still getting enough of what their growing body needs.
- A peer reviewed study of national claims data followed 2,031 teens, ages 10 to 17, who started a GLP1 medication with no prior nutritional deficiency on record.
- Within a year, 16.8% were newly diagnosed with a nutritional deficiency. Vitamin D deficiency alone accounted for 12.4%.
- Only 5% of these teens received documented nutrition counseling within the first 30 days of starting the drug, and fewer than 25% had received it even within six months.
- This is association from claims data, not proof the drugs directly cause deficiency. The study's own numbers point at least as strongly toward a monitoring gap.
What the study found
Researchers led by a team at Ann and Robert H. Lurie Children's Hospital of Chicago screened a national administrative claims database covering more than 100 million patients between 2017 and 2022. They identified 2,031 continuously enrolled 10 to 17 year olds who started a GLP1 medication with no prior nutritional deficiency diagnosis on record. Within one year, 16.8% of them were newly diagnosed with a nutritional deficiency, most commonly low vitamin D, which alone accounted for 12.4%.
The monitoring side of the data is just as striking. Only 5% of these teens received documented nutrition counseling within 30 days of starting the drug, and fewer than 25% had received it even within six months. The medication mix in this cohort skewed heavily toward liraglutide, an older and less potent GLP1 drug, at 78.6%, with dulaglutide at 10.4% and semaglutide at only 9.1%, a reflection of the study's 2017 to 2022 window, well before semaglutide and tirzepatide became the dominant choices in pediatric prescribing.
A monitoring story, not necessarily a drug mechanism story
The study's own authors frame this as association, not proof of direct cause. A deficiency diagnosis could reflect a real biological effect of the drug, genuinely low monitoring that would have found similar rates in any teen population if anyone had looked, or some mix of both. The fact that only 5% of teens got nutrition counseling within a month is itself a strong reason to read this as a gap in follow up care as much as a signal about the drug. Vitamin D, iron, and calcium status during adolescence matter for bone development in particular, which is what makes the counseling gap worth taking seriously either way.
Honest caveat
This is retrospective claims and diagnostic code data, not a clinical trial with lab confirmed measurements. It captures what a clinician actually coded, which can over or under count real deficiency depending on documentation habits, and it shows association rather than proven causation. The cohort is also dominated by liraglutide because of the study's 2017 to 2022 window, so how well the 16.8% and 12.4% figures generalize to today's more commonly prescribed semaglutide and tirzepatide is genuinely unknown. This is a single study, not yet replicated.
What this means for you
If a teenager in your life is starting or already on a GLP1 medication, this is a concrete, specific thing to bring up with the prescriber, not a reason for alarm about the drug itself. Ask whether nutritional status, vitamin D in particular, along with iron and calcium, is being checked and monitored over time, and ask what nutrition counseling looks like as part of the treatment plan. The honest takeaway here is less about the medication and more about making sure the follow up care actually happens.
Primary sources
- Ryder J, et al. "Nutritional Deficiencies Among Adolescents Prescribed GLP1 Receptor Agonists," Childhood Obesity, September 21, 2026
- EurekAlert / Ann and Robert H. Lurie Children's Hospital of Chicago: institutional press release, September 21, 2026
- News Medical: coverage of the Lurie Children's Hospital study
Common questions
Does this study prove GLP1 drugs cause nutritional deficiencies in teens?
No. This is an association found in claims data, not a controlled trial, and the study's own headline finding, that only 5% of teens got nutrition counseling in the first 30 days, supports a monitoring gap explanation at least as much as a direct drug effect. Low monitoring can produce a higher diagnosis rate on its own.
Which nutrient deficiency was most common?
Vitamin D. Of the 16.8% of teens diagnosed with any nutritional deficiency within a year of starting a GLP1 medication, vitamin D deficiency alone accounted for 12.4%, the single largest share.
Does this apply to teens on newer drugs like semaglutide or tirzepatide?
That is genuinely unclear. The study's data runs from 2017 to 2022, a period dominated by liraglutide, an older and less potent GLP1 drug, with semaglutide making up only about 9% of the cohort. How well these rates generalize to today's more commonly prescribed drugs has not yet been tested.
Stay Curious.
Better health isn't found in a single article. It's built through curiosity, evidence, and small discoveries over time. Join thousands exploring longevity, gut health, recovery, nutrition, and the tools that truly make a difference.