TOPLINE:

Over 1 year, metabolic bariatric surgery (MBS) was associated with a higher risk for multiple micronutrient deficiencies than GLP-1 receptor agonist (GLP-1 RA) therapy. It was also linked to more than sixfold higher frequency of new vitamin B₁₂ prescriptions, a higher risk for certain metabolic complications, and a lower risk for neuropathies than GLP-1 RA therapy.

METHODOLOGY:

• Both MBS and GLP ‑ 1 RAs are effective treatments for obesity. Although bariatric surgery is associated with micronutrient malabsorption resulting in hematologic, metabolic, skeletal, and neurologic complications, data on nutrient outcomes after initiation of GLP-1 RAs remain limited.
• Researchers conducted a retrospective cohort study using data from the TriNetX Research Network, leveraging de-identified electronic health records from 111 healthcare organizations, to compare 1-year incidence of vitamin or mineral deficiencies following MBS vs GLP-1 RA therapy.
• The study included matched cohorts of adults aged 18 years or older who underwent MBS (n = 79,002) or initiated GLP-1 RA therapy (n = 79,002); those with preexisting micronutrient deficiencies or chronic malabsorption conditions were excluded.
• Outcomes assessed were new diagnoses of vitamin B or D deficiency, calcium deficiency, iron deficiency anemia, osteoporosis or bone density disorders, neuropathies, nausea or vomiting, hypokalemia, visits to the emergency department, and new vitamin B₁₂ prescriptions over 1 year.

TAKEAWAY:

• At 1 year, patients who underwent MBS had higher risks for vitamin D deficiency (risk ratio [RR], 1.26), vitamin B group deficiency (RR, 1.39), calcium deficiency (RR, 15.40), and iron deficiency anemia (RR, 1.26; P < .0001 for all) than GLP-1 RA users.
• Post-index vitamin B₁₂ prescriptions were 6.75-fold more frequent after MBS than after GLP-1 RA therapy (P < .0001).
• MBS was associated with increased risks for osteoporosis or bone density disorders (RR, 1.69), hypokalemia (RR, 1.80), nausea or vomiting (RR, 1.75), and visits to the emergency department (RR, 1.27; P < .0001 for all).
• The risk for neuropathies was 62% lower after MBS than after GLP-1 RA therapy (P < .0001).

IN PRACTICE:

“This data supports the need for structured postoperative nutritional surveillance after MBS and routine micronutrient monitoring for patients on GLP-1 RAs. As utilization of both therapies accelerates, optimizing long-term outcomes based on nutritional safety profiles is critical for physicians to consider,” the authors wrote.

SOURCE:

This study was led by Krishna Kothamasu, Jefferson Health Northeast in Philadelphia. It was presented at Digestive Disease Week (DDW) 2026 in Chicago.

LIMITATIONS:

This study did not mention any limitations.

DISCLOSURES:

No funding details or conflicts of interest were provided for the study.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.