Calorie & Macro Calculator

Tiffany Mercer

BMR: Mifflin MD, St Jeor ST, et al. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr. 1990;51(2):241-247. PMID 2305711.
Activity envelope (PAL): FAO/WHO/UNU Human Energy Requirements; US Institute of Medicine, Dietary Reference Intakes for Energy.
Rate of loss: CDC healthy weight guidance (about 1-2 lb/week via a 500-1,000 kcal/day deficit; 5-10% loss yields health benefit).
Weight floor: CDC / WHO BMI classification (underweight below 18.5; healthy 18.5-24.9).
Body fat ranges: American Council on Exercise (ACE) body fat norms; cycle-health risk below about 17% for women.
Surplus / gain rate: Iraki J, Fitschen P, Espinar S, Helms E. Nutrition Recommendations for Bodybuilders in the Off-Season. Sports. 2019;7(7):154. PMID 31247944.
Protein: ISSN Position Stand (Jager et al. 2017), 1.4-2.0 g/kg; Morton et al. 2018 meta-analysis (breakpoint about 1.6 g/kg).
Fat: 20-35% of calories (IOM AMDR); floor about 0.5-1 g/kg for hormone health.