Optimizing Your Medical Weight Loss Journey
Obesity and overweight remain leading drivers of chronic illness, including type 2 diabetes, hypertension, and cardiovascular disease. Recent clinical advances are offering unprecedented efficacy in pharmacologic therapy for weight management and medical weight loss—and primary care is on the front lines.
Many of our patients ask how GLP-1 medications differ and which is the right choice for them. Within our practice, every medical decision is personalized with shared decision-making between our doctors and our patients. However, the medications are distinct.
Tirzepatide and semaglutide are both injectable medications used for type 2 diabetes, medical weight loss, but they act on slightly different targets:
- Semaglutide is a GLP-1 receptor agonist, which mimics the gut hormone GLP-1 to slow stomach emptying, increase satiety, and improve blood sugar control.
- Tirzepatide is a dual GIP and GLP-1 receptor agonist, meaning it activates both GLP-1 and another hormone pathway called GIP (glucose-dependent insulinotropic polypeptide). This dual action appears to enhance appetite suppression and metabolic effects, leading to greater average weight loss in clinical trials compared to semaglutide.
In short: semaglutide works on one hormone pathway, while tirzepatide works on two, which likely explains its greater weight-loss results in head-to-head studies.
The SURMOUNT-1 Clinical Trial
The phase 3 SURMOUNT-1 trial evaluated tirzepatide—a dual GIP/GLP-1 receptor agonist—in adults with overweight or obesity (but without diabetes), alongside lifestyle intervention for 72 weeks. Results were impressive:
- At 72 weeks, mean weight loss ranged from –15% (5 mg) up to –20.9% (15 mg), compared to –3.1% with placebo (all p < 0.001) American College of Cardiology.
- More than 90% of patients on 15 mg tirzepatide lost at least 5% of their body weight American College of Cardiology.
- In longer follow-up (up to 176 weeks), weight loss remained substantial (e.g. –18.7% at 10 mg, –19.7% at 15 mg), with significantly reduced progression to type 2 diabetes (only 0.4% in the 15 mg group vs. 13.3% in placebo) American College of Cardiology.
- A secondary analysis showed tirzepatide reduced progression from prediabetes to diabetes by 94%, with improvements in glycemic control, fasting insulin, and blood pressure.
SURMOUNT-5 and Head-to-Head Trial
A pivotal direct comparison between tirzepatide (Zepbound) and semaglutide (Wegovy) in people with obesity (without diabetes) over 72 weeks showed:
- Tirzepatide produced a mean weight loss of approximately 20.2% vs. 13.7% with semaglutide—a statistically significant difference of about 6.5 percentage points.
- Tirzepatide patients saw a mean waist circumference decrease of 18.4 cm (7.2 in) vs. 13.0cm (5.1 in) for those on semaglutide (both differences were statistically significant p <0.001).
- Both agents produced mostly mild to moderate gastrointestinal side effects (nausea, vomiting, etc.), with similar tolerability profiles and slightly lower discontinuation rates for tirzepatide.
Medical Weight Loss in Primary Care
We work with a variety of patients who are at different stages of their medical weight loss journey. Ideal candidates include those with obesity or overweight with comorbidities, or type 2 diabetes not at goal with lifestyle modification.
This new evidence—from SURMOUNT-1 and direct comparisons like SURMOUNT-5—solidly reinforces tirzepatide as a breakthrough in obesity pharmacotherapy, surpassing semaglutide in weight reduction, metabolic benefits, and diabetes prevention. However, semaglutide still has remarkable efficacy within this space and can be an excellent option for some patients. As first-line touchpoints, primary care providers are pivotal in evaluating candidacy, managing therapy, mitigating side effects, and overcoming barriers to access. Integrating these advancements offers a powerful opportunity to meaningfully reverse disease trajectories in patients with metabolic risks and optimize healthspan and lifespan.
We help patients achieve weight loss success by combining diet, exercise, prescription medications, and personalized recommendations that are evidenced-based and are realistic for your life.
Feel free to contact our office for a free meet and greet appointment with Dr. Mintz or Dr. Taskier today to discuss medical weight loss.