Peptide Guides
In-depth, evidence-based educational resources. Every claim is cited, every statement rated by the strength of supporting research.
Featured Guides
What Are Peptides? A Science-Based Introduction
Understand the basics of peptide biology — what they are, how they work in the body, and why researchers study them.
Peptides for Weight Loss: What the Research Shows
A comprehensive comparison of peptides studied for weight management — from FDA-approved GLP-1 drugs to research compounds.
Peptide Therapy: What You Need to Know Before Starting
A comprehensive, evidence-based overview of peptide therapy for patients considering treatment: what it is, what it costs, how to find a provider, and what the science supports.
Peptides for Muscle Growth: What the Research Actually Shows
An honest, evidence-rated review of peptides studied for muscle growth and body composition, including growth hormone secretagogues, healing peptides, and the muscle-sparing properties of GLP-1 drugs.
Are Peptides Safe? What the Evidence Shows
An honest, evidence-based assessment of peptide safety covering side effects, quality risks, drug interactions, and what we know (and do not know) about long-term safety.
All Guides
FDA Regulation of Peptides: What You Need to Know
Navigate the complex regulatory landscape of peptides, from approved medications to research chemicals.
Understanding Our Evidence Ratings
How PeptideMark evaluates and rates the scientific evidence behind each peptide compound.
Growth Hormone Secretagogues Explained
An overview of GHS peptides — CJC-1295, Ipamorelin, Sermorelin, and more — with research context.
GLP-1 Receptor Agonists: From Semaglutide to Retatrutide
The science behind GLP-1 RAs, their mechanisms of action, clinical trial results, and current regulatory status.
How to Reconstitute Peptides: Step-by-Step
A detailed walkthrough of reconstituting lyophilized peptides with bacteriostatic water, including dosage calculations.
Peptide Storage & Handling Best Practices
How to properly store, handle, and maintain peptide integrity — temperature, light exposure, and shelf life considerations.
How to Read Peptide Research Papers
A guide to evaluating peptide studies — understanding study design, sample sizes, statistical significance, and common pitfalls.
Peptide Injection Sites: Subcutaneous vs Intramuscular Guide
A practical reference for injection sites: subcutaneous vs intramuscular, body-region selection, rotation patterns, and common mistakes.
Peptide Half-Life Reference: Dosing Frequency & Duration
A practical reference on peptide half-life: why it matters, how it determines dosing frequency, and a compound-by-compound table.
Peptide Needle & Syringe Guide: Gauge, Length, and Sizing
A practical reference for selecting insulin syringes, needle gauges, and needle lengths for subcutaneous peptide injection.
Peptide Dosing Timing: When to Inject and Why It Matters
A practical guide to timing peptide doses: morning vs bedtime, fasted vs fed, and how common cycle structures work.