Do GLP-1 Medications Work Differently by Age, Race, or Starting Weight?

Direct Answer

Do GLP-1 medications work differently by age, race, or starting weight? No, largely not. A March 2026 meta-analysis led by Johns Hopkins Bloomberg School of Public Health, published in JAMA Internal Medicine, found GLP-1 receptor agonists produce similar weight-loss results regardless of age (under 65 vs. 65+), race, ethnicity, starting BMI, or starting blood sugar level.

The Real, Substantial Study Behind This

Researchers analyzed 64 clinical trials covering close to 20,000 participants, examining semaglutide (Ozempic), dulaglutide (Trulicity), and other GLP-1 receptor agonists. Tirzepatide (Zepbound) was specifically excluded from this analysis since it also activates a separate hormone pathway (GIP), making it mechanistically distinct.

The One Real, Confirmed Difference: Sex

The one meaningful, statistically significant difference researchers found was between men and women, women lost an average of about 11% of starting body weight, compared to about 7% for men. Researchers proposed several possible explanations, including interactions with estrogen, differences in how women's bodies process the medication, and women's generally lower median starting body weight.

Why This Finding Matters

Per senior author Dr. Hemalkumar Mehta, this gives clinicians and patients real, evidence-based confidence that GLP-1 medications work similarly well across different racial, ethnic, age, and weight groups, directly addressing a real, previously open question about whether these medications' benefits might vary meaningfully by patient demographics.

Bottom Line

If you're wondering whether your age, race, or starting weight will affect how well a GLP-1 medication works for you, the real, current evidence says it largely won't, sex is the one demographic factor genuinely shown to matter to how much weight you're likely to lose on average.

References

• JAMA Internal Medicine: Heterogeneity of GLP-1 Receptor Agonist Treatment Effects on Weight Loss (March 2, 2026)
• Johns Hopkins Bloomberg School of Public Health: official press release (March 2026)

Explore More

Explore the full GLP-1 Tracker knowledge base on DietApp.com

Get Started

Explore the GLP-1 Tracker knowledge base for accurate, sourced information on every GLP-1 medication.

About DietApp.com

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.