GLP-1 protein calculator: how much protein do you need?
A daily protein target for people on Zepbound, Ozempic, Wegovy, Mounjaro, or compounded semaglutide/tirzepatide. Built on the 1.2–1.6 g/kg range from published clinical guidance and adjusted body weight, because plain body weight tends to overshoot at higher BMIs. No account needed.
Used for the ideal-body-weight formula only.
The evidence behind this calculator
The formula is adjusted body weight (Devine ideal weight + 25% of any excess over it) multiplied by 1.2 to 1.6 g/kg. Each part is anchored to a source below, and the parts that are our own judgment are labeled as such.
- Protein range during active weight loss (1.2–1.6 g/kg/day), the 80–120 g/day alternative, and the 2 g/kg/day ceiling: Mozaffarian et al. 2025, Nutritional priorities to support GLP-1 therapy for obesity: a joint Advisory from ACLM, ASN, OMA, and TOS, Obesity.
- Adjusted body weight (ideal + 0.25 × excess), the Joslin Diabetes Center definition as cited in: Mechanick et al. 2025, Strategies for minimizing muscle loss during use of incretin-mimetic drugs for treatment of obesity, Obesity Reviews 26(1):e13841.
- Splitting protein across at least four meals (~0.4 g/kg per meal): Schoenfeld & Aragon 2018, How much protein can the body use in a single meal for muscle-building?, JISSN 15:10.
What is our judgment, not the literature's
- The activity-level mapping. The advisory gives a range, not a point per activity level. We place sedentary at 1.2, light at 1.3, moderate at 1.5, and active at 1.6 g/kg. That is an interpolation inside the sourced range — the range itself is the evidence-based part.
- The weight basis. The advisory says it is unclear whether these targets should be based on actual body weight, corrected (adjusted or ideal) body weight, or fat-free mass, and that actual weight can significantly overestimate requirements. We chose adjusted body weight; a clinician with your body-composition data may reasonably choose differently.
- The even four-meal split. We divide your daily number by four for simplicity. Schoenfeld & Aragon frame four meals as a minimum, not a rule.
No randomized trial has yet established an optimal g/kg specifically for people on GLP-1 medications. This calculator is educational, not medical advice — talk to your prescriber or a registered dietitian before making significant changes to your intake, especially if you have kidney concerns.
Protein is half of it. The same advisory says protein alone is likely inadequate to preserve muscle without structured resistance training. See the muscle preservation guide →
Frequently asked questions
- How much protein do I need on Zepbound, Ozempic, or Wegovy?
- A 2025 joint advisory from four US medical societies (ACLM, ASN, OMA, and TOS) notes that 1.2–1.6 g of protein per kg of body weight per day has been proposed during active weight reduction, compared with the 0.8 g/kg/day recommended for the general adult population. As a simpler alternative, the same advisory suggests an absolute target of 80–120 g per day. This calculator shows where you fall in the 1.2–1.6 g/kg range.
- Is the protein target different for Zepbound (tirzepatide) than for Ozempic (semaglutide)?
- No. The advisory addresses GLP-1 receptor agonists and combination medications as one group and does not set different protein targets by drug or dose. What changes with a stronger drug or a higher dose is how hard the target is to reach, because appetite is lower.
- Why does this calculator use adjusted body weight instead of my actual weight?
- The advisory states that using actual body weight can significantly overestimate protein requirements for people with obesity, and that it is unclear whether targets should be based on actual, adjusted, or ideal body weight, or on fat-free mass. We use adjusted body weight — ideal body weight plus 25% of the weight above it, the Joslin Diabetes Center definition cited in Mechanick et al. 2025 — as a middle path. It is a reasonable choice, not a settled one.
- Can you eat too much protein on a GLP-1?
- The advisory says prolonged intake at or above 2 g/kg/day should be avoided due to potential adverse health effects, which is why this calculator never goes above 1.6 g/kg. If you have kidney disease or reduced kidney function, ask your prescriber before raising your protein intake at all.
- Is hitting my protein target enough to prevent muscle loss?
- Probably not on its own. The advisory says increased protein intake alone is likely inadequate to preserve muscle mass without structured resistance training, and recommends strength training at least three times weekly plus at least 150 minutes of moderate-intensity aerobic exercise per week.
Related reading
How Much Protein Do You Actually Need on Ozempic, Wegovy, or Mounjaro?
The article behind this calculator — why the target matters and how to hit it when appetite is low.
Read article →Muscle Loss After Stopping GLP-1: Why You Likely Regain Fat, Not Muscle
What SURMOUNT-1 DXA data shows about body composition during and after GLP-1 therapy.
Read article →The First 8 Weeks After Your Last GLP-1 Dose, Week by Week
When protein habits matter most — the post-therapy window where lean mass is on the line.
Read article →
Want to track protein against this target week over week?
GLP-1 Coach tracks daily protein against your target, alongside weight, side effects, and resistance activity — so the number on this page doesn't just sit in your head, it shows up in your weekly pattern.
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