For research use only — not intended for human consumption. All content is educational.

Methodology

How we work

Fonvita's research standards, citation methodology, and editorial guidelines.

Citation sourcing

All citations are pulled from PubMed via the NCBI E-utilities API and verified via Crossref DOI resolution. We do not cite secondary sources, blog posts, or forum threads. If a claim cannot be traced to a peer-reviewed publication, it does not appear on this site.

Calculator methodology

Calculator logic is derived from published clinical trial protocols or peer-reviewed pharmacokinetic studies. Tirzepatide titration follows the SURMOUNT-1 protocol. Retatrutide titration follows the Eli Lilly Phase 2b trial (NCT04881383). Half-life data is sourced from published pharmacokinetic studies for each peptide.

Research standards

We prioritize randomized controlled trials and peer-reviewed pharmacokinetic studies. Where RCT data does not exist, we cite the best available evidence and note the limitation explicitly. We do not extrapolate beyond what the data supports.

Affiliate disclosure

Fonvita earns commission on purchases made through affiliate links to peptide research suppliers. Affiliate relationships do not influence editorial content, calculator logic, or research summaries. Supplier recommendations are based on third-party testing, COA availability, and community reputation — not commission rates.

Updates and corrections

Research evolves. When new data contradicts existing content, we update it. If you identify an error or have a citation that updates our content, contact us. We will review and correct within 48 hours if warranted.

Disclaimer

All content is for research and educational purposes only. Nothing on this site constitutes medical advice. Peptides discussed are for research use only unless otherwise noted by regulatory bodies. Consult a licensed physician before use.