Micronutrient and Nutritional Deficiencies Associated With GLP-1 Receptor Agonist Therapy: A Narrative Review

Area of Science:

• Endocrinology and Metabolism
• Nutritional Science

Background:

• Glucagon-like peptide-1 receptor agonists (GLP-1RA) are widely used for type 2 diabetes mellitus (T2DM) and obesity.
• Potential micronutrient deficiencies associated with GLP-1RA therapy warrant clinical investigation due to increasing usage.

Purpose of the Study:

• To evaluate the impact of GLP-1RA therapy on nutritional and micronutrient status in adults.
• To identify common deficiencies and assess intake relative to recommendations.

Main Methods:

• A structured literature search of PubMed and Cochrane Database (Jan 2019-May 2025) was performed.
• Included adult studies with nutrient endpoints; excluded pediatric studies, reviews, and those lacking specific outcome measures.
• Data synthesis followed SANRA and PRISMA-ScR guidelines, with descriptive analysis.

Main Results:

• Six observational studies involving 480,825 adults were analyzed.
• Vitamin D deficiency was prevalent (7.5% at 6 months, 13.6% at 12 months).
• GLP-1RA users showed lower ferritin levels (26-30%) vs. SGLT2 inhibitors; over 60% had inadequate calcium and iron intake; vitamin D intake was 20% of recommendations. Protein and calcium insufficiency linked to lean mass loss; thiamine and cobalamin deficits increased over time.

Conclusions:

• GLP-1RA therapy is associated with significant nutritional deficiencies, including vitamin D, iron, calcium, protein, thiamine, and cobalamin.
• Targeted nutritional assessment and laboratory evaluation are recommended for at-risk patients.
• Causality cannot be definitively established due to reliance on observational data.