Study decoded · nutrition · Emerging

Nearly 17% of Teens on GLP-1 Drugs Develop Nutrient Deficiency Within a Year

2,031 Teens Studied16.88% Had Deficiency12.4% Vitamin D Deficiency23.3% Got Counseling149 Days to First Visit

A claims-data study published in Childhood Obesity found that 16.88% of teenagers prescribed GLP-1 weight-loss drugs developed a nutritional deficiency within one year of starting the medication.

Researchers analyzed Inovalon administrative claims data collected from 2017 to 2022, covering more than 100 million patients, and identified 2,031 patients ages 10 to 17 who started a GLP-1 receptor agonist and had no prior diagnosis of a nutrient deficiency. Average age came in at 15 years old, plus or minus 1.8 years, with girls making up 61.5% of the group and 62.6% already carrying an obesity diagnosis. Most were prescribed liraglutide (78.6%), followed by dulaglutide (10.4%) and semaglutide (9.1%). Within one year, 16.88% of these teens were diagnosed with at least one nutritional deficiency or related complication. Vitamin D deficiency was most common, affecting 12.4%, followed by nutritional anemia in 1.55% and iron-deficiency anemia in 1.44%. Only 23.3% of patients saw a nutrition therapy or counseling provider within 180 days of starting the drug, and the average time to that first visit was 149 days. Teens who did receive nutrition counseling had a higher deficiency rate than those who did not — 23.2% versus 14.8%.

Nutrient Deficiency Rate: 23.2% With Counseling vs 14.8% Without

Nutrient Deficiency Rate: 23.2% With Counseling vs 14.8% Without2,031 teens ages 10-17 on GLP-1 drugs, tracked for 1 year. Received nutrition counseling: 23.2 %; No nutrition counseling: 14.8 %2,031 teens ages 10-17 on GLP-1 drugs, tracked for 1 year23.2RECEIVED NUTRITIONCOUNSELING14.8NO NUTRITIONCOUNSELING%
Childhood Obesity, 2026

The study authors did not test why deficiencies occurred, but GLP-1 drugs work by slowing stomach emptying and suppressing appetite, which sharply cuts how much food a person eats. Eating less across the board makes it harder to take in enough vitamin D, iron, and other nutrients that come from a varied diet, especially during the growth years when requirements are higher. The higher deficiency rate among teens who did get nutrition counseling likely reflects that counseling was often triggered after a problem was already found, rather than counseling causing the deficiency.

This is an observational analysis of insurance claims, not a controlled trial, with no comparison group of teens with obesity who did not take a GLP-1 drug, so it cannot separate the effect of the medication from reduced eating in general, and diagnosis codes likely miss deficiencies that were never tested for. Funding and conflicts of interest were not reported in the abstract.

Data Panel

Who
2,031 patients ages 10-17 who started a GLP-1 receptor agonist for obesity, prediabetes, or type 2 diabetes; average age 15 (±1.8 years), 61.5% female, 62.6% with obesity
Design
Retrospective analysis of Inovalon administrative claims data from 2017 to 2022, covering more than 100 million patients, tracking new nutritional deficiency diagnoses for up to 1 year after GLP-1RA initiation
Dose
Liraglutide 78.6%, dulaglutide 10.4%, and semaglutide 9.1% of prescriptions; specific doses not reported in the abstract
Primary result
Within the first year on a GLP-1 drug, 16.88% of teens developed a new nutritional deficiency or related complication
Secondary
Vitamin D deficiency 12.4%, nutritional anemia 1.55%, iron-deficiency anemia 1.44%; only 23.3% had a nutrition therapy/counseling visit within 180 days (mean time to first visit 149 days); those with counseling had higher deficiency rates than those without (23.2% vs 14.8%)
Funding / conflicts
Not reported in the abstract

Dr. Axe's Take

This does not surprise me. GLP-1 drugs work by shutting down appetite, and a child eating dramatically less will take in less of everything, including vitamin D, iron, and B12. A 12.4% vitamin D deficiency rate in previously healthy teens after one year on these drugs is a warning sign. If a child is on a GLP-1 medication, I want a nutrition consult built into that plan from day one, not 149 days later, with baseline and follow-up labs checking vitamin D, iron, and B12. Keep the medication as prescribed and work with the treating doctor on any nutrient gaps, anchoring meals with protein, colorful produce, and whole foods.

Dr. Axe— Dr. Axe