Pic2Cal uses scientifically validated formulas to calculate your Basal Metabolic Rate (BMR) and personalized daily caloric goals. This page provides detailed information about the calculations and their scientific sources.
Basal Metabolic Rate (BMR) represents the number of calories your body needs to maintain basic physiological functions at rest, including breathing, circulation, cell production, and nutrient processing. It accounts for approximately 60-75% of your total daily energy expenditure.
Understanding your BMR is essential for:
Pic2Cal primarily uses the Mifflin-St Jeor Equation, which is widely recognized as one of the most accurate predictors of BMR in modern populations.
For Men:
BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age in years) + 5
For Women:
BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age in years) - 161
Mifflin, M. D., St Jeor, S. T., Hill, L. A., Scott, B. J., Daugherty, S. A., & Koh, Y. O. (1990). A new predictive equation for resting energy expenditure in healthy individuals. The American Journal of Clinical Nutrition, 51(2), 241-247.
https://doi.org/10.1093/ajcn/51.2.241
Why this formula? The Mifflin-St Jeor equation was developed based on a study of 498 healthy individuals and has been validated as more accurate than the older Harris-Benedict equation, particularly for modern populations with different lifestyle patterns.
Some versions of Pic2Cal may also use the revised Harris-Benedict equation, another well-established method for BMR calculation.
For Men:
BMR = 88.362 + (13.397 × weight in kg) + (4.799 × height in cm) - (5.677 × age in years)
For Women:
BMR = 447.593 + (9.247 × weight in kg) + (3.098 × height in cm) - (4.330 × age in years)
Roza, A. M., & Shizgal, H. M. (1984). The Harris Benedict equation reevaluated: resting energy requirements and the body cell mass. The American Journal of Clinical Nutrition, 40(1), 168-182.
https://doi.org/10.1093/ajcn/40.1.168
This is a revision of the original Harris-Benedict equation from 1919, updated with modern data to improve accuracy.
Your BMR is just the baseline. To calculate your total daily caloric needs, we multiply BMR by an activity factor based on your lifestyle:
| Activity Level | Description | Multiplier |
|---|---|---|
| Sedentary | Little or no exercise | BMR × 1.2 |
| Lightly Active | Light exercise 1-3 days/week | BMR × 1.375 |
| Moderately Active | Moderate exercise 3-5 days/week | BMR × 1.55 |
| Very Active | Hard exercise 6-7 days/week | BMR × 1.725 |
| Extra Active | Very hard exercise & physical job | BMR × 1.9 |
Institute of Medicine (US) Subcommittee on Military Weight Management. (2004). Weight Management: State of the Science and Opportunities for Military Programs. Washington (DC): National Academies Press (US). Chapter 3: Factors That Influence Body Weight.
When you set weight goals in Pic2Cal, the app adjusts your daily caloric target based on established principles:
Hall, K. D., & Kahan, S. (2018). Maintenance of Lost Weight and Long-Term Management of Obesity. Medical Clinics of North America, 102(1), 183-197.
Donnelly, J. E., Blair, S. N., Jakicic, J. M., Manore, M. M., Rankin, J. W., & Smith, B. K. (2009). American College of Sports Medicine Position Stand. Appropriate physical activity intervention strategies for weight loss and prevention of weight regain for adults. Medicine and Science in Sports and Exercise, 41(2), 459-471.
Pic2Cal may also provide macronutrient (protein, carbohydrates, fat) recommendations based on your goals. These are derived from established nutritional guidelines:
General Guidelines:
Institute of Medicine (2005). Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. The National Academies Press, Washington, DC.
Phillips, S. M., & Van Loon, L. J. (2011). Dietary protein for athletes: from requirements to optimum adaptation. Journal of Sports Sciences, 29(sup1), S29-S38.
General Health Information: The calculations provided by Pic2Cal are based on widely accepted scientific formulas and are intended for general informational and educational purposes only. They are not a substitute for professional medical advice, diagnosis, or treatment.
Individual Variation: BMR and caloric needs can vary significantly based on individual factors including genetics, body composition, metabolic health conditions, medications, and other variables not captured by these formulas.
Consult Healthcare Professionals: Before starting any weight loss, weight gain, or exercise program, please consult with a qualified healthcare provider, registered dietitian, or nutritionist, especially if you have any pre-existing health conditions.
Not Medical Advice: Pic2Cal is a nutrition tracking tool and does not provide medical advice. The AI-powered food recognition and nutritional estimates are approximate and should be verified for critical dietary needs.
For more information about nutrition and energy expenditure, please refer to these authoritative sources:
