Glossary
GLP-1 glossary
Plain-language definitions of the 20 terms that come up most on Ozempic, Wegovy, Mounjaro, and Zepbound — from gastric emptying and lean mass to titration and telogen effluvium.
- Constipation
- Constipation on a GLP-1 is caused by slower gut transit, lower food volume, and reduced fluid intake rather than by the drug damaging the bowel.
- Dehydration
- Dehydration is common on GLP-1 medications because appetite suppression also blunts thirst signalling.
- Electrolytes
- Electrolytes are minerals — mainly sodium, potassium, and magnesium — that regulate fluid balance, nerve signalling, and muscle contraction.
- Gastric emptying
- Gastric emptying is the rate at which food leaves the stomach; GLP-1 medications slow it, which extends fullness and can cause nausea or bloating.
- GIP
- GIP is a second incretin hormone that works alongside GLP-1 to regulate insulin, fat handling, and appetite.
- GLP-1
- GLP-1 (glucagon-like peptide-1) is a gut hormone released after eating that stimulates insulin, slows gastric emptying, and reduces appetite.
- GLP-1 receptor agonist
- A GLP-1 receptor agonist is a medication that binds the GLP-1 receptor to reduce appetite, slow gastric emptying, and improve blood sugar control.
- Gut microbiome
- The gut microbiome is the community of bacteria in the digestive tract that influences digestion, immunity, and GLP-1 production.
- Lean mass
- Lean mass is body weight that is not fat — mostly muscle, bone, and water — and 25–40% of GLP-1 weight loss can come from it without protein and training.
- Magnesium glycinate
- Magnesium glycinate is a highly absorbable, gentle form of magnesium used for sleep, muscle relaxation, and cramp prevention.
- Nausea
- Nausea is the most common GLP-1 side effect, peaking 24–72 hours after a dose and usually easing within two to four weeks at each dose level.
- Protein
- Protein is the macronutrient that preserves muscle during weight loss; GLP-1 users should target 0.7–1.0 g per pound of goal body weight daily.
- Sarcopenia
- Sarcopenia is the progressive loss of skeletal muscle mass and strength, which rapid weight loss can accelerate.
- Semaglutide
- Semaglutide is a GLP-1 receptor agonist sold as Ozempic and Rybelsus for type 2 diabetes and as Wegovy for chronic weight management.
- Soluble fiber
- Soluble fiber dissolves in water to form a gel that softens stool and slows digestion, making it the preferred fiber type for GLP-1 constipation.
- Telogen effluvium
- Telogen effluvium is temporary diffuse hair shedding triggered by rapid weight loss, low protein, or nutrient shortfalls — not by GLP-1 drugs directly.
- Tirzepatide
- Tirzepatide is a dual GIP/GLP-1 receptor agonist sold as Mounjaro for type 2 diabetes and Zepbound for chronic weight management.
- Titration
- Titration is the scheduled stepping-up of a GLP-1 dose over weeks or months to improve tolerance.
- Weight-loss plateau
- A plateau is four or more weeks without weight change, driven by a lower metabolic rate, muscle loss, or unmeasured intake creep.
- Whey protein
- Whey protein is a fast-digesting complete dairy protein with a high leucine content, making it efficient for preserving muscle on low food volume.