Guides
Every guide in the Atlas in one place. Start with the beginner guide if you are new, or jump to the question you have.
The beginner guide
Twelve short chapters, from what obesity is to what happens when you stop. Read them in order or pick one.
- What obesity is, and what BMI can and cannot tell you
A plain definition, why BMI is only a screening number, and why this guide treats weight as biology rather than willpower. - Why weight is hard to keep off
Appetite hormones change after weight loss, and some of those changes last. That is part of why regain is common. - How GLP-1 and related medicines work
The gut hormones behind today's weight-loss medicines, in plain English. - The medicine classes at a glance
A map of what exists today and what is still in the pipeline. - How to read the trial numbers
Averages, placebo groups and the word "estimand", explained with real trial figures. - Side effects and safety, in general terms
What trials commonly report, why some labels carry boxed warnings, and where the official details live. - Getting care: questions to ask, cost and access
A checklist of questions for a prescriber, and the difference between approved and compounded products. - Eating well on medication
What changes when appetite drops, how to handle nausea and constipation, protein figures that experts have proposed, and questions for a dietitian. - Protecting muscle and strength
What trials measured about lean mass during weight loss, and what is known about strength training. - Stopping, pausing and maintaining
What happened to weight and health markers after people stopped treatment in trials, and what to plan before you do. - Special situations
Type 2 diabetes, adolescents, pregnancy and breastfeeding, and surgery, according to trials and current labels. - Costs, insurance and access
How coverage works, what the Medicare bridge program is, and the difference between approved and compounded products.
Getting started
How starting treatment usually works, from the first form to the first dose.
From decision to first dose
Every stage in order, with what happens and what to have ready.
The intake form, question by question
What you will be asked, why they ask, and a worksheet to fill in before you start.
Your first visit and what comes next
What a good visit covers, what to leave with, and the first weeks.
Side effects, week by week
When digestive side effects show up as the dose goes up, how common they are, and when to call.
Compounded versus brand-name
What the FDA says, what changed when the shortages ended, and what to ask.
What a 503A pharmacy is
How compounding works, why it costs less, and what FDA-approved does and does not cover.
What are semaglutide and tirzepatide?
The two medicines in plain English, and whether compounded versions are the same thing.
What to watch for in injection instructions
A checklist, red flags and questions for your clinic or pharmacy. It does not show how to inject.
Brand-name pen instructions, from the makers
A plain-English walk through the written instructions for the Zepbound, Mounjaro and Wegovy pens, with links to the originals.
Protecting muscle
How much weight lost is lean mass, what helps, and which muscle-saving drugs are in trials.
Paying for GLP-1 medicines
Insurance, Medicare, maker cash prices and savings offers, and how to compare costs.
Choosing an online service
Questions to ask before you sign up. The Atlas does not rate or list any service.
Eating and exercise
Each page keeps trial evidence, expert guidance and community experience apart.
Protein and high-protein eating
Protein helps protect muscle during weight loss, and a smaller appetite can make it hard to eat enough.
Constipation on GLP-1 medicines
Constipation is one of the most common side effects of GLP-1 medicines.
Nausea, fullness and food
Nausea is the most common side effect of GLP-1 medicines.
Hydration and fluids
Fluids matter on GLP-1 medicines mostly because vomiting, diarrhea and eating less can leave you short of fluid.
Eating enough and avoiding nutrient gaps
When appetite drops, you can fall short on protein, vitamins and minerals without noticing.
Exercise and strength training
Exercise is one of the few add-ons tested alongside a GLP-1 medicine in a year-long trial.
Mediterranean-style eating
Mediterranean-style eating centers on vegetables, fruit, beans, whole grains, nuts, fish and olive oil, with little processed food.
Low-carb and keto eating
Low-carb eating cuts back on bread, sugar and starch.
Intermittent fasting
Intermittent fasting means eating only within certain hours or on certain days.
Alcohol on GLP-1 medicines
Expert guidance says alcohol can worsen nausea and reflux on GLP-1 medicines and should be kept low.
Eating after you stop
Weight usually comes back after stopping a GLP-1 medicine.
Tools
Evidence, policy and providers
Trial results
Charted, with comparison groups and limits.
Pipeline
Medicines in trials, from phase 1 to 3.
Sleep apnea and medicines
Tirzepatide and retatrutide trial results.
News
Recent decisions and trial results.
Peptide policy tracker
Compounding rules and the July 2026 FDA votes.
Providers
How to size one up. The Atlas lists no one.
Where our information comes from
Sources and method.
Not medical advice. The guides explain what has been studied and reported. A licensed clinician who knows your history decides what is right for you.