Myths about peptides, read against the science
Each article takes one claim people repeat online and reads it against trials, labels, regulators, and reviews.
Explore the myths
Side effects and safety
Worries about symptoms, organs, and warning signs.
01Some hair falls on GLP-1, and it grows backYes, some people lose more hair on these peptides. Not many. And the hair grows back.02GLP-1 does not attack teeth, but the conditions around it canNot directly. The peptide doesn't attack teeth. The conditions around it can.03The evidence linking GLP-1 to erectile dysfunction is thinThere's one observational study suggesting a small effect in non-diabetic obese men. The evidence is thin, and no trial designed to test this has reported yet.04No clear mechanism ties GLP-1 to lower libidoThere's no clear mechanism in the literature that says the peptide lowers libido. The signal hasn't been studied directly in a trial.05Ozempic face is fat loss, not the peptide aging your skinThe face does look different. The reason is fat loss, not the peptide.06Loose skin follows the weight loss, not the peptideLoose skin follows weight loss, not the peptide itself.07Some muscle goes with GLP-1, but fat falls fasterYes, some lean-mass loss happens. And that's true of every weight-loss method, not just peptides. The body-composition studies show fat falls more than lean.08GLP-1 does not strip vitamins, it cuts how much food comes inThe peptide doesn't remove vitamins from the body. It reduces how much food the body takes in. If the food drops without the nutrient quality going up, vitamin intake can fall below what the body needs.09GLP-1 does not dry you out, eating and drinking less around it canNot directly. The peptide doesn't dry the body out. Eating and drinking less around the peptide can.10Constipation is one of the most common GLP-1 side effectsYes. Constipation is one of the most common side effects of these peptides.11Nausea is common and expected, especially while the dose climbsYes. Nausea is a common, expected gastrointestinal effect with GLP-1 receptor agonist treatment, especially during dose escalation.12Slower stomach emptying is how GLP-1 works, paralysis overstates itSlower stomach emptying is part of how semaglutide works. "Paralysis" often overstates the routine effect, but severe or persistent retention needs clinical evaluation.13The kidney risk runs through dehydration from severe GI symptomsThe labeled kidney warning centers on acute kidney injury from volume depletion during severe GI reactions.14Direct liver injury is not a primary GLP-1 safety signalDirect liver injury isn't a primary safety signal for these peptides.15Gallbladder problems are a real risk, and so is fast weight lossYes. And so does fast weight loss itself. This is a real safety topic.16Pancreatitis risk is real, and the absolute rate is lowAcute pancreatitis is a labeled warning. The absolute rate in trials is low. The symptom pattern is severe persistent abdominal pain.17Human data show no clear thyroid-cancer signal, but the boxed warning staysThe labels still carry a boxed warning from rodent C-cell tumor findings. Human studies are broadly reassuring over short-to-moderate follow-up, but the label treats the human relevance as unresolved.
Body, weight, and fertility
Visible changes, muscle, metabolism, libido, and reproduction.
18FDA's 2026 review found no increased suicide risk across 91 trialsFor suicidal ideation or behavior, FDA's January 2026 review did not find increased risk across 91 trials covering 107,910 patients and requested removal of that warning.19Infertility is not an established GLP-1 risk, pregnancy timing is the real concernInfertility is not an established human label signal here. The source-backed concern is pregnancy planning and fetal-risk avoidance, especially semaglutide's two-month washout window before planned pregnancy.20Tirzepatide affects oral birth control, semaglutide's label does not say soFor tirzepatide (Mounjaro and Zepbound), the label is explicit. For semaglutide (Ozempic and Wegovy), it isn't.21A rare optic-nerve signal exists, and the absolute rates are lowRare, but real. The eye-disease research shows a small signal involving an optic-nerve condition, and the absolute rates are low.22About two-thirds of the lost weight returns after stoppingYes, much of it. About two-thirds of the lost weight came back in the studies that followed people after they stopped.23GLP-1 does not wreck metabolism, weight loss slows it either wayNo. Significant weight loss reduces resting energy expenditure with or without the peptide. The adaptation is real but not specific to peptides.24Weight-loss peptides are not addictive the way stimulants areAre weight loss peptides addictive? Not in the stimulant-opioid-sedative sense. Current evidence points toward reduced compulsive reward signaling, not escalating reinforcement.
Trust, sourcing, and quality
What a source, COA, or side effect can prove, and what it cannot.
25The molecule is identical on paper, the supply chain is notNo. The molecule is the same on paper. The supply system isn't.26A certificate of analysis is necessary, not sufficientA certificate of analysis is necessary, not sufficient.27Mild side effects are how the peptide works, not proof it is badAre side effects proof of bad peptide quality? No. In GLP-class compounds, low-to-moderate GI effects are often part of the expected mechanism pattern, not automatic evidence of defective product.