Protein calculator for weight loss on GLP-1
Work out a daily protein range from your weight, and how to split it across your meals, so you lose fat and keep muscle.
Medically reviewed by Dr. Nezar Dahdal, Medical Director · last reviewed September 2026
Protein calculator for weight loss
Enter your current weight. The range shown is the daily protein intake research links to keeping muscle while losing fat, which matters most on GLP-1 medications that reduce appetite.
Enter your weight to see a daily range.
A general range, not a personal prescription. If you have kidney disease or another condition that affects protein intake, ask your clinician before changing your diet.
Why protein is the weak point on GLP-1 therapy
Semaglutide and tirzepatide work partly by making you feel full sooner. The side effect is that meals shrink, and protein usually shrinks with them. When weight comes off fast on too little protein, a larger share of it is muscle, which lowers the calories you burn at rest and makes regain more likely.
Spreading protein across meals, rather than saving it for dinner, makes the target easier to reach when your appetite is small. Starting each meal with the protein portion helps too.
Measure it, don't guess
A bathroom scale cannot tell muscle from fat. An InBody body composition scan can, segment by segment, which is how our clinicians check that weight loss on GLP-1 therapy is coming from fat.
Sources
- Leidy HJ et al. The role of protein in weight loss and maintenance. Am J Clin Nutr, 2015. PubMed
- Jastreboff AM et al. Tirzepatide Once Weekly for the Treatment of Obesity (SURMOUNT-1). N Engl J Med, 2022. PubMed
- Wilding JPH et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1). N Engl J Med, 2021. PubMed
Answers before you book
How much protein do I need to lose weight?
Research on weight loss supports about 1.2 to 1.6 grams of protein per kilogram of body weight a day, roughly 0.55 to 0.73 grams per pound. That is well above the general recommendation of 0.8 g/kg, because a higher intake helps protect muscle while you lose fat.
Why does protein matter more on a GLP-1 medication?
GLP-1 medications reduce appetite, so people often eat less protein without noticing. Losing weight quickly on too little protein raises the share of weight lost as muscle rather than fat.
Should I use my current weight or my goal weight?
This calculator uses your current weight, which is the common approach. If you carry a lot of excess weight, your clinician may suggest basing it on a goal or adjusted weight instead.
How do I know I am keeping muscle?
A body composition scan separates muscle from fat, which a scale cannot. We use InBody scans at the start and every four to six weeks.
Want a clinician to check your plan?
Book a free GLP-1 consultation, in person in Mission Viejo or by telehealth anywhere in California. No insurance needed.