GLP-1 Medications Explained

GLP-1 receptor agonists — Ozempic, Wegovy, Mounjaro, Zepbound, Trulicity — reshape diabetes care and weight loss in 2026. Here’s a non-medical, fact-first overview of what they are, how they work, and what the cultural conversation often gets wrong. Not medical advice; talk to your doctor.

What they are

Glucagon-like peptide-1 (GLP-1) is a natural gut hormone released after eating. GLP-1 agonists are synthetic versions taken weekly (or daily, in older formulations) that mimic this hormone. They were originally developed for type-2 diabetes; the weight-loss effect was a discovered side effect that became the headline.

The current lineup

• Semaglutide (Ozempic, Wegovy, Rybelsus) — weekly injection (Ozempic / Wegovy) or daily oral (Rybelsus).
• Tirzepatide (Mounjaro, Zepbound) — weekly. GLP-1 + GIP dual agonist; modestly more potent.
• Liraglutide (Saxenda, Victoza) — daily injection; older.
• Retatrutide — triple agonist, late-stage trials in 2026, expected to be even more potent.

How weight loss works

Slowed gastric emptying + reduced appetite signaling. People feel full sooner and stay full longer. Average weight loss in trials: ~15% of body weight on semaglutide, ~22% on tirzepatide. Compare to behavioral-only programs at 5-7%.

Trade-offs

• Side effects: nausea, constipation, fatigue (early weeks). Most resolve.
• Muscle loss: ~25-40% of weight lost can be lean mass without strength training. Lift weights.
• Stop = regain: most people regain 60-80% of weight within a year of stopping. They’re generally a long-term medication.
• Cost: $900-1,500/month US retail; insurance coverage is uneven. Compounded versions cheaper but less reliable.

What gets oversimplified

• It’s not a “quick fix” — without diet + strength training, results are inferior and easier to lose.
• It’s not just for the obese — doctors prescribe at lower BMIs for cardiometabolic risk in 2026.
• The cultural “Ozempic face” is real (subcutaneous fat loss) but reversible with hydration + protein + lifting.

For longevity-style fitness practices to layer alongside, see zone 2 heart rate calculator and VO2 max estimator. This page is informational, not medical advice.