How to Calculate GLP-1 Calorie Needs

What is GLP-1 Calorie Needs?

The GLP-1 Adjusted Calorie Needs calculator recalculates your total daily energy expenditure (TDEE) while accounting for the appetite-suppressing effects of GLP-1 medications. It estimates how your caloric requirements change as you lose weight on these medications and helps prevent excessive calorie restriction.

Formula

Adjusted TDEE = BMR × Activity Factor × (1 - Metabolic Adaptation %) where BMR recalculated at projected weight

BMR: Basal Metabolic Rate (cal/day) — Calories burned at complete rest
AF: Activity Factor (1.2-1.9) — Multiplier based on physical activity level
MA: Metabolic Adaptation (%) — Reduction in metabolic rate beyond what weight loss alone predicts (typically 5-15%)
TDEE: Total Daily Energy Expenditure (cal/day) — Total calories burned per day including activity

Step-by-Step Guide

1Enter your current weight, height, age, sex, and activity level to calculate baseline TDEE
2Input your GLP-1 medication and current dose
3The calculator estimates your reduced appetite-driven intake and adjusts TDEE for weight loss-induced metabolic adaptation
4View recommended daily calorie targets to ensure adequate nutrition while maximizing weight loss

Worked Examples

Input

200 lb male, 5'10", age 40, moderate activity, on Wegovy 2.4 mg, 20 lbs lost

Result

Original TDEE: 2,640 cal. Adjusted TDEE at 180 lbs: 2,480 cal. With 10% metabolic adaptation: 2,232 cal. Recommended intake range: 1,500-1,800 cal/day for continued loss.

Input

170 lb female, 5'5", age 35, light activity, on Mounjaro 10 mg

Result

Original TDEE: 1,920 cal. Recommended minimum intake: 1,200 cal/day. Warning: appetite suppression may drive intake below 1,000 — ensure adequate protein and micronutrients.

Common Mistakes to Avoid

✕Eating too little (under 1,000 cal/day) due to extreme appetite suppression, leading to muscle loss and nutrient deficiencies
✕Not recalculating TDEE as weight drops — your calorie needs decrease with every 10 lbs lost
✕Ignoring the difference between appetite reduction (eating less) and metabolic adaptation (burning less)

Frequently Asked Questions

How many calories should I eat on Ozempic or Wegovy?

Most guidelines recommend women consume at least 1,200 calories and men at least 1,500 calories daily, even with appetite suppression. Your specific target depends on your starting weight, activity level, and rate of loss. Aim for the range that produces 1-2 lbs/week loss while meeting protein goals (typically 60-100g/day).

Will my metabolism slow down on GLP-1 medications?

Yes, some metabolic adaptation occurs with any weight loss. Studies suggest a 5-15% reduction in metabolic rate beyond what is expected from reduced body mass alone. This is one reason weight loss plateaus after 12-18 months. Resistance training can help mitigate this effect.

Ready to calculate? Try the free GLP-1 Calorie Needs Calculator

Try it yourself →