Your questions

GLP-1 Frequently Asked Questions

Plain-English answers to the most common questions about Ozempic, Wegovy, Mounjaro and Zepbound — how they work, how much weight you can lose, side effects, safety, cost, and more. Updated regularly as the science evolves.

About GLP-1 Medications

About GLP-1 Medications

What is a GLP-1 and how does it work?
GLP-1 (glucagon-like peptide-1) is a natural gut hormone released after eating. GLP-1 receptor agonist medicines such as semaglutide and tirzepatide mimic it: they prompt insulin release when blood sugar is high, slow stomach emptying, and increase fullness, which lowers blood sugar and reduces appetite. Tirzepatide also activates a second receptor, GIP.
How much weight can you lose on GLP-1 medications?
In randomized trials, semaglutide 2.4 mg led to about 14.9% average body-weight loss over 68 weeks (STEP 1, 2021), and tirzepatide up to about 20.9% over 72 weeks (SURMOUNT-1, 2022). A 2025 head-to-head trial found tirzepatide averaged 20.2% versus 13.7% for semaglutide. Individual results vary.
What is the difference between Ozempic, Wegovy, Mounjaro, and Zepbound?
Ozempic and Wegovy are both semaglutide; Mounjaro and Zepbound are both tirzepatide. Ozempic and Mounjaro are approved for type 2 diabetes, while Wegovy and Zepbound are approved for weight management. Tirzepatide acts on two hormone receptors (GIP and GLP-1); semaglutide acts on one.
Injectable or oral: which GLP-1 works better?
Both exist. Semaglutide comes as a weekly injection and as a daily pill (Rybelsus). Injectable versions generally produce stronger, more consistent results because more of the medicine is absorbed, but a daily pill suits people who prefer not to inject. The best choice depends on your goals and tolerance.
Nutrition & lifestyle

Nutrition & Lifestyle

Can a supplement replace a GLP-1 drug, and is berberine 'nature's Ozempic'?
No. No supplement has been shown to match GLP-1 medicines. Berberine, often called 'nature's Ozempic,' works through a different pathway (AMPK) and has weak human weight-loss evidence far below the drug data. The nickname is marketing, not proven equivalence.
What is 'food noise'?
'Food noise' is the term for constant, intrusive thoughts and cravings about food. Many people taking GLP-1 medicines report that this mental chatter quiets noticeably, reflecting the drugs' effects on appetite-regulating pathways. It is a widely reported experience rather than a formal clinical measurement.
Weight loss & side effects

Weight Loss & Side Effects

What happens when you stop taking a GLP-1 medication?
Most of the lost weight tends to return. In the STEP 1 trial extension, participants regained about two-thirds of their lost weight within a year of stopping semaglutide, as appetite and cravings come back. This is why clinicians treat obesity as a chronic condition and GLP-1s are generally used long-term.
What are the most common side effects of GLP-1 drugs?
The most common side effects are gastrointestinal: nausea, diarrhea, vomiting, and constipation. They are usually mild to moderate and worst while the dose is being increased, so doses are raised slowly to improve tolerability. Rare but serious risks exist, so these drugs are taken under medical supervision.
Do GLP-1 medications cause muscle loss?
Some muscle (lean mass) is lost along with fat. Studies suggest roughly 25 to 40 percent of total weight lost can come from lean mass, though some of that is fluid. This is not unique to GLP-1s; any major weight loss does it. Adequate protein and resistance exercise help preserve muscle.
Who should not take GLP-1 medications?
According to the FDA labels, semaglutide and tirzepatide are contraindicated for people with a personal or family history of medullary thyroid carcinoma (MTC) or MEN2 syndrome, and for anyone with a serious allergy to the drug. They are also not recommended in pregnancy. Always confirm suitability with a clinician.
Are GLP-1 medications safe during pregnancy?
No. GLP-1 medicines are not recommended during pregnancy or breastfeeding, and their safety for a developing baby has not been established. Because semaglutide stays in the body for weeks, guidance is to stop it well before trying to conceive. Discuss timing with your doctor.
Health, cost & access

Health, Cost & Access

Do GLP-1 drugs protect the heart?
For semaglutide, yes in one major trial. In SELECT (2023), among people with cardiovascular disease and overweight or obesity but without diabetes, semaglutide reduced major cardiac events (heart attack, stroke, or cardiovascular death) by 20% versus placebo. Whether tirzepatide does the same is still being tested.
Is there a generic Ozempic, and what about compounded versions?
There is no FDA-approved generic semaglutide or tirzepatide; US brand list prices run around $1,000 per month without insurance. Compounded copies were widely sold during 2022 to 2024 shortages, but the FDA declared those shortages resolved in 2025 and has moved to end broad compounding.

New questions are added as the science and community questions evolve.

This page is educational and not medical advice. Always consult your clinician before changing medication, diet or exercise.

Join the waitlist

Be first to repair your nutritional gaps

Keep the weight loss. Fill the nutritional gap