Two Pharma Companies Now Own Nearly 100% of GLP-1 Citations Inside ChatGPT, Claude and Perplexity, New 5W Index Finds

Five GLP-1 brands capture 57% of all AI citations in the $150 billion weight loss and metabolic health category; legacy programs and supplements losing visibility in real time

NEW YORK, May 19, 2026 /PRNewswire/ -- Two pharmaceutical companies — Novo Nordisk and Eli Lilly — now own nearly 100% of GLP-1 citations inside the AI tools where Americans research weight loss, according to The Weight Loss & Metabolic Health AI Visibility Index 2026, released today by 5W, the premier AI communications and GEO firm in the United States.

The index ranks the top 25 U.S. brands in the weight loss and metabolic health category by their share of citations across ChatGPT, Claude, Perplexity and Google AI Overviews. It is the fourth installment in 5W's AI Visibility Index series, following editions on Legal Tech, Real Estate and Fintech.

Five GLP-1 receptor agonists — Wegovy, Zepbound, Ozempic, Mounjaro and Saxenda — together capture roughly 57% of all category citations. The four leading brands alone capture 55%. Novo Nordisk and Eli Lilly are the only sources of FDA-approved options for chronic weight management and the only sources of the peer-reviewed clinical trial data — STEP, SURMOUNT and SELECT — that AI models cite as evidence.

The Top 15 by AI Citation Share:

1. Wegovy — 19.0%
2. Zepbound — 16.0%
3. Ozempic — 13.0%
4. Mounjaro — 7.0%
5. Noom — 7.0%
6. WeightWatchers — 7.0%
7. MyFitnessPal — 6.0%
8. Lose It! — 3.0%
9. Cronometer — 2.0%
10. Simple — 2.0%
11. Saxenda — 2.0%
12. Factor — 1.5%
13. Optavia — 1.5%
14. Jenny Craig — 1.0%
15. Nutrisystem — 1.0%

The remaining ~11% of citation share is split across ranks 16–25 and unranked brands. Telehealth providers and compounded-medication marketplaces are excluded from this edition and will be covered in a forthcoming index.

The Citation Compounding Dynamic

The index identifies clinical trial publication as the highest-leverage citation event in the category. Zepbound's recent trajectory illustrates the dynamic. SURMOUNT-5, the head-to-head trial against Wegovy published in 2025, demonstrated superior weight loss for tirzepatide. That single data point is now cited in nearly every "Wegovy vs Zepbound" AI answer, and the citation itself has driven prescription volume.

"Two pharmaceutical companies now own nearly 100% of GLP-1 citations in AI answers. Six pharma brands take roughly 58% of the entire category. That is not a market share story. It is a marketing infrastructure story," said Ronn Torossian, founder of 5W. "Novo Nordisk and Eli Lilly built the citation moat the same way every other category leader will eventually have to build it: peer-reviewed clinical data, named-author editorial coverage, regulatory events treated as content events, and a content cadence faster than the news cycle. AI citation share is the scoreboard. Most brands in this category are not yet playing."

Pivots, Moats and Collapse

The index identifies three winning playbooks and three losing categories.

Behavioral programs Noom and WeightWatchers have pivoted into the GLP-1 era with very different financial outcomes but similar citation outcomes. Noom's 2022 launch of Noom Med positioned the company as "behavioral change plus medication access," and AI now cites it as the category's hybrid default. WeightWatchers filed Chapter 11 in 2025 and emerged with a GLP-1-centric strategy, but its citation share has held because of more than 60 years of accumulated brand equity and editorial coverage.

MyFitnessPal, owned by Francisco Partners, is cited in an estimated 60–70% of "best diet app" AI answers. Its 15-year head start on food-database construction and 200 million-plus user base create an informational moat that newer apps cannot displace through product quality alone.

The losers: legacy behavioral brands (Jenny Craig, Nutrisystem, Optavia) are increasingly framed in AI answers as "before GLP-1s, people tried...". Meal delivery is being recategorized as an adjunct to medication-based weight loss. The OTC supplement category — Hydroxycut, Leanbean, PhenQ and Garcinia products — has lost nearly all generic citation share to GLP-1s and Plenity, with AI models flagging supplement claims with evidence caveats.

Methodology

5W analyzed more than 60 common consumer prompts across five sub-categories — pharmaceutical GLP-1s, behavioral programs, diet and nutrition apps, packaged meal services, and supplements — running each through ChatGPT, Claude, Perplexity and Google AI Overviews in Q1 2026. Citation sources tracked include WebMD, Healthline, GoodRx, the NIH, Mayo Clinic, Forbes Health, U.S. News Health, Reddit, CNBC, Bloomberg, STAT News and FiercePharma.

The index is a marketing and communications research document. It does not rank products on clinical effectiveness, safety or appropriateness, and does not constitute medical advice.

Download

The full index, including the methodology, the top 15 ranking, six structural truths, six 2026 dynamics and the 10-point Weight Loss Marketer Playbook, is available as an ungated PDF at: 5wpr.com/research/weight-loss-ai-visibility-index-2026

About 5W

5W is the AI Communications Firm — building brand authority across the platforms where decisions now happen: ChatGPT, Claude, Perplexity, Gemini, and Google AI Overviews, alongside earned media, digital, and influencer channels. 5W combines public relations, digital marketing, Generative Engine Optimization (GEO), and proprietary AI visibility research to help clients measure and grow their presence in AI-driven buyer research.

Founded in 2002, 5W is recognized as a Top U.S. PR Agency by O'Dwyer's, named Agency of the Year in the American Business Awards®, honored as a 2026 Top Place to Work in Communications by Ragan, and named to Digiday's WorkLife Employer of the Year list. 5W serves clients across B2C sectors — Beauty & Fashion, Consumer Brands, Entertainment, Food & Beverage, Health & Wellness, Travel & Hospitality, Technology, and Nonprofit — and B2B specialties including Corporate Communications, Reputation Management, Public Affairs, Crisis Communications, and Digital Marketing across Social, Influencer, Paid Media, GEO, and SEO.

Learn more at 5wpr.com

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SOURCE 5W Public Relations