Not medical advice. Talk to your provider before using any peptide.
Full disclaimerPeter Attia's GLP-1 Clinical Perspective
Peter Attia prescribes GLP-1 agonists clinically and flagged the lean mass loss problem early: 39% of weight lost in the STEP 1 trial was lean tissue. His protocol follows standard FDA titration (0.25mg to 1mg+ weekly) but pairs it with resistance training and 1g protein per pound of bodyweight. This is a prescriber's perspective, not personal biohacking. DEXA scans and metabolic panels required.
Peptide Schedule Research TeamReviewed Apr 2026
A clinical prescriber's perspective on GLP-1 agonists for weight loss, emphasizing lean mass preservation through resistance training and high protein intake.
What This Protocol Does
Standard FDA titration of semaglutide (0.25mg to 1mg+ weekly) or tirzepatide, paired with mandatory resistance training and 1g protein per pound of bodyweight. Attia flagged the lean mass loss problem before most practitioners: 39% of weight lost in the STEP 1 trial was lean tissue. This protocol treats muscle preservation as equally important to fat loss. DEXA scans track body composition changes over time.
Who Should Use This
Anyone considering GLP-1 agonists who wants a physician-informed framework. Beginner-friendly from a dosing standpoint (follows FDA titration), but requires commitment to resistance training and high protein intake. Budget $200-1,000 per month depending on brand vs. compounded. Requires HbA1c, lipid panel, DEXA scan, and metabolic panel before starting. Not a biohacking protocol; this is standard clinical practice with added lean mass monitoring.
What the Research Says
Semaglutide 2.4mg weekly produced 14.9% body weight reduction in the STEP 1 trial (Wilding et al., PMID 33567185). Tirzepatide 15mg weekly produced 22.5% reduction in SURMOUNT-1 (Jastreboff et al., PMID 35658024). Attia's concern about lean mass loss is supported by STEP 1 data showing 39% of weight lost was lean tissue. A 2023 study in Obesity (PMID 36740879) confirmed resistance training partially mitigates this effect.
Important Notices
- Prescriber perspective — Attia prescribes these, not personal biohacking
- 39% of weight loss in STEP 1 trial was lean mass — resistance training is essential
- GI side effects common during titration
- Do not combine with other GLP-1 agonists
Protocol Overview
Recommended Labwork
- HbA1c
- Lipid panel
- Body composition (DEXA)
- Metabolic panel
Recommended Supplements
- Whey protein · 1g/lb bodyweight daily — Counteract lean mass loss
- Creatine · 5g daily — Support muscle retention
Dosing Details
| Peptide | Dose | Frequency | Route | Weeks |
|---|---|---|---|---|
| 250mcg | Weekly | subcutaneous (abdomen) | Weeks 1-4 | |
| 500mcg | Weekly | subcutaneous (abdomen) | Weeks 5-8 | |
SemaglutideMaint. | 1mg | Weekly | subcutaneous (abdomen) | Week 9+ |
Semaglutide: Standard FDA titration. Attia emphasizes resistance training + 1g/lb protein alongside.
Semaglutide: Increase to 0.5mg weekly. Monitor GI side effects.
Semaglutide: Maintenance at 1mg weekly. Attia notes 39% lean mass loss concern.
Metrics Tracked
Schedule This Protocol
Set your start date and track every dose in your calendar.
Peptide Profiles & Calculators
Related Weight Loss Protocols
Semaglutide Titration Protocol (Ozempic/Wegovy)
Semaglutide
FDA-standard weekly titration from 0.25mg to 2.4mg over 16+ weeks. Hold current dose for an extra 4 weeks if GI side effects are severe.
Tirzepatide Titration Protocol (Mounjaro/Zepbound)
Tirzepatide
FDA-standard weekly titration from 2.5mg to 15mg. Many maintain at 7.5-10mg without reaching max dose.
Retatrutide Titration Protocol (Triple G)
Retatrutide
Phase 3 trial protocol: weekly titration from 1mg to 12mg. Triple GLP-1/GIP/Glucagon agonist with up to 24% weight loss in clinical trials.
Semaglutide Microdose
Semaglutide
Semaglutide at 0.025-0.05mg weekly, roughly 1/10th the standard starting dose. Dr. Tyna Moore's philosophy: "Dose up to appetite control, not suppression." Exact microgram dose is not publicly verified; the approach and philosophy come from multiple interviews including Ben Greenfield Life. She treats GLP-1 as scaffolding for building metabolic habits, not a permanent prescription.
Bryan Johnson's Tirzepatide Microdose (DISCONTINUED)
Tirzepatide
Three weeks, then done. Johnson tried tirzepatide at 0.5mg weekly (1/5th the standard starting dose) and halted when his data turned negative: resting heart rate up 3bpm, HRV down 7 points, sleep quality down 10%. He already had optimal metabolic markers, so the risk outweighed any benefit. This is some of the best-documented peptide discontinuation data available, with exact biomarker numbers attached.