🚨 Real-World GLP-1 Data: Vanderbilt Obesity Clinic Study (n=2,306)
Clinical trials showed 15–21% weight loss with semaglutide & tirzepatide. But how do patients actually fare in practice?
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Key Findings:
📊 Median treatment duration: 10.7 months (50% discontinued by 12 months)
💉 Only 23% reached semaglutide 2.4 mg, 28% reached tirzepatide 15 mg
⚖️ Weight loss for those who continued treatment:
• 6 months: –9.4%
• 12 months: –14.4%
🏥 13.6% had medication-related ER visits (mostly GI side effects)
Context:
This was not a typical setting—patients had multidisciplinary support and NO-COST medication access through employer insurance bundles.
Reality Check:
✅ With the right care model, real-world outcomes can approach RCTs
❌ Most patients never reach target doses
❌ Half stop treatment within a year
A triple-agonist just posted 30% weight loss at two years. Surgical-magnitude, from a once-weekly shot.
And I'm convinced it's the least important thing that happened to obesity medicine this year. Here's why the biggest number stopped being the story. 🧵
1/ For three years, we ranked these drugs like a leaderboard:
Semaglutide: ~15%.
Tirzepatide: ~21%.
Then retatrutide crossed 28%.
Every year, a bigger number.
We got very good at asking one question: how much weight comes off? That's now the wrong question.
2/ What actually changed in 2026: the class now pulls four different levers.
🔹GLP-1: eat less, ⬇️ inflammation, ⬇️ glucose
🔹GIP: tolerate more, sharpen insulin response
🔹Glucagon: burn more, clear liver fat
🔹Amylin: eat less through a separate circuit, ⬆️ leptin sensitivity
My patient lost almost no weight on semaglutide. His liver healed. His blood pressure dropped. His sleep apnea lifted. His knees stopped hurting. He barely moved the scale and got better everywhere else.
I'd been measuring the wrong thing for years. 🧵
1/ My patient Marcus came to me to lose weight. A year on semaglutide, he'd lost under 5%.
By my specialty's scoreboard: a non-responder. Then I looked at the rest of his chart.
2/ A1c: normal.
Liver enzymes, elevated for years: normal. Blood pressure: down.
The snoring his wife complained about: gone. His knees on the stairs: better.
He lost only a modest amount of weight, but almost every marker of his health improved. anyway.
A patient asked me this week if they could stop their obesity medication.
I told them what the data says:
67% of people who stop regain almost everything within a year.
That's not a failure of willpower. That's biology. And we finally have trials that prove it.
1/ ECO 2026 just changed the conversation in obesity medicine. For 3 years, every major meeting asked: how much weight can we lose? Istanbul asked something different: how do we keep it? Here's what we learned. 🧵
2/ SURMOUNT-MAINTAIN published in The Lancet this week. After losing 22% of their weight on tirzepatide, patients were randomized to continue full dose, drop to 5 mg, or switch to placebo. The results were unambiguous.
Every morning I take five things.
A statin. Ezetimibe. Psyllium. Creatine. A multivitamin.
Once a week, I add a sixth: tirzepatide.
No rapamycin. No NMN. No Bryan Johnson protocol.
Here's what the evidence actually says—and why I left everything else out. 🧵
1/ Every morning I take five things.
A statin. Ezetimibe. Psyllium. Creatine. A multivitamin.
Once a week, I add a sixth: tirzepatide.
I used to raise an eyebrow at longevity stacks. Then I realized I'd quietly built one—each addition requiring enough evidence to clear the same bar I hold my prescriptions to.
2/ The plaque that ruptures at 62 was building in the third decade or earlier.