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Free GLP-1 Protein Calculator

Find your daily protein target on Ozempic, Wegovy, Mounjaro or Zepbound to preserve lean mass during weight loss. Evidence-based, 1.2–2.0 g/kg goal weight per Obesity Medicine Association.

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References & sources

  1. [1]Obesity Medicine Association. Clinical Practice Statement: Protein Intake and Exercise for Optimal Muscle Mass Preservation in Patients Treated with Anti-Obesity Medications. Obes Pillars. 2024.
  2. [2]Wilding JPH, Batterham RL, Calanna S, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1). N Engl J Med. 2021;384(11):989-1002.
  3. [3]Jastreboff AM, Aronne LJ, Ahmad NN, et al. Tirzepatide Once Weekly for the Treatment of Obesity (SURMOUNT-1). N Engl J Med. 2022;387(3):205-216.
  4. [4]Ida S, Kaneko R, Imataka K, et al. Effects of Antidiabetic Drugs on Muscle Mass in Type 2 Diabetes Mellitus. Curr Diabetes Rev. 2021;17(3):293-303.
  5. [5]Cava E, Yeat NC, Mittendorfer B. Preserving Healthy Muscle during Weight Loss. Adv Nutr. 2017;8(3):511-519.
  6. [6]Academy of Nutrition and Dietetics. Adult Weight Management (AWM) Evidence-Based Nutrition Practice Guideline. 2022.

Medical disclaimer

This calculator is an educational tool only. GLP-1 medications (semaglutide, tirzepatide, liraglutide) are prescription drugs that require physician supervision. Protein, calorie, and hydration targets should be individualised by your prescribing clinician and a registered dietitian based on your labs, comorbidities, tolerability, and response to therapy. Do not start, stop, or adjust any medication based on this tool.

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よくある質問

How much protein do I need on Ozempic, Wegovy or Mounjaro?

The Obesity Medicine Association recommends 1.2 to 2.0 grams of protein per kilogram of goal body weight for people on weight-loss medications. Active weight-loss phases sit at the upper end (around 1.6-1.8 g/kg) to protect lean tissue; maintenance phases can ease to 1.2-1.4 g/kg.

Why is protein so important on GLP-1 medications?

Landmark trials show that 25 to 39 percent of weight lost on semaglutide and tirzepatide comes from lean mass, not fat. Adequate protein combined with resistance training shifts that ratio — more of the loss becomes fat, preserving strength, metabolism and long-term weight maintenance.

I can barely eat anything — how do I realistically hit these numbers?

Anchor every meal with protein first (before carbs or veg). Use protein-forward snacks like Greek yoghurt, cottage cheese, boiled eggs, jerky, or whey isolate shakes. Liquid protein is a lifesaver during severe nausea. Spread intake across 4-5 smaller servings rather than 3 large meals.

Should I also track fibre and hydration?

Yes. GLP-1 medications slow gastric emptying and reduce thirst cues, which commonly causes constipation and dehydration. Target at least 25-35 g fibre daily and 30-35 ml of fluid per kg of body weight. Both support gut health, satiety between doses, and medication tolerability.

Is this calculator a substitute for medical advice?

No. This tool provides evidence-based starting points drawn from Obesity Medicine Association guidance and peer-reviewed literature. Your prescriber or a registered dietitian should adjust these targets based on your labs, comorbidities, and clinical response.