CalcCafe

GLP-1 Protein & Calorie Calculator

On Ozempic, Wegovy, Zepbound, or Mounjaro, appetite drops fast — making it easy to under-eat protein and lose muscle. This tool sets a daily protein and calorie target tuned for muscle preservation during weight loss.

Mifflin-St Jeor BMR + GLP-1 protein guidance

Daily protein target
0 g
BMR (Mifflin-St Jeor)0 kcal
Maintenance (TDEE)0 kcal
Calorie target0 kcal
Protein per meal (3 meals)0 g
Protein as % of calories0%

Educational estimate only — not medical advice. GLP-1 medications, calorie targets, and protein needs should be discussed with your prescriber, especially if you have kidney disease or other conditions. Don't drop below ~1,200 kcal/day without medical supervision.

Worked example

A 42-year-old man, 210 lb (95.3 kg), 5'8" (172.7 cm), light activity, aiming to lose weight at the recommended 1.6 g/kg protein: BMR ≈ 1,829 kcal, TDEE ≈ 2,515 kcal, calorie target ≈ 2,015 kcal (500 deficit), and a protein target of ≈ 152 g/day — about 51 g per meal across three meals.

How the calculation works

  1. BMR via Mifflin-St Jeor: men = 10·kg + 6.25·cm − 5·age + 5; women = 10·kg + 6.25·cm − 5·age − 161.
  2. TDEE = BMR × activity factor.
  3. Calorie target = TDEE − your chosen deficit (clamped to a 1,200 kcal floor).
  4. Protein = protein intensity (g/kg) × body weight in kg. On a GLP-1 deficit, 1.6–2.0 g/kg is commonly recommended to protect lean mass.

FAQ

Why higher protein on a GLP-1?
Appetite suppression makes under-eating easy, and rapid weight loss risks muscle. Higher protein + resistance training preserves lean mass.
Should I use current or goal weight?
This tool uses current body weight for a simple, safe target. Some clinicians use lean or goal weight for very high BMIs — ask your provider.
Is this calorie target safe?
It floors at 1,200 kcal, but individual needs vary. Confirm with your prescriber.