Vitamins and Supplements to Consider on a GLP-1 Medication

Direct Answer

Real, published research has documented meaningful nutrient shortfalls in GLP-1 users, particularly vitamin D, vitamin B12, iron, and magnesium, largely a consequence of significantly reduced overall food intake. A basic multivitamin, plus targeted support for specific, documented gaps, is a reasonable, evidence-informed approach, though this is genuinely worth confirming directly with your provider rather than adding supplements on your own without guidance.

What the Real Research Shows

A 2026 study found roughly 13.6% of GLP-1 users had vitamin D deficiency at 12 months, and ferritin (iron stores) levels were 26 to 30% lower on average, findings covered in more detail on our nutrient deficiency page. This isn't a hypothetical concern, it's real, documented, and part of why the ADA's 2026 Standards of Care specifically recommend nutrition monitoring alongside dose tracking.

Nutrients Worth Specific Attention

Protein, covered in depth on our protein guide, is the single most important nutrient for preserving muscle during weight loss. Magnesium has real, specific evidence for helping GLP-1-related constipation. Vitamin D and B12 are both documented as commonly low in this population and worth discussing with your provider about testing rather than assuming supplementation is automatically needed.

Why Testing Matters More Than Guessing

Rather than supplementing broadly and hoping it addresses gaps you may or may not actually have, real bloodwork, covered on our labs guide, tells you specifically what you're genuinely low on, letting you supplement deliberately rather than by assumption.

Bottom Line

Given documented, real nutrient shortfalls in this population, a basic multivitamin plus attention to protein intake is a reasonable starting approach, but real bloodwork and a direct conversation with your provider is the more precise, evidence-based way to know exactly what you personally need.

References

• Urbina et al. Clinical Obesity (January 2026)
• American Diabetes Association: 2026 Standards of Care

Related Resources

• Which Nutrients Are GLP-1 Users Actually Falling Short On? What 2026 Research Shows
• What Labs Should You Get Before and During GLP-1 Treatment?
• Protein
• Magnesium

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DietApp.com combines evidence-based GLP-1 medication education with practical treatment tracking tools. This article is for general informational purposes and is not medical advice.