Scientific sources — Constance

Constance estimates your energy needs and your macronutrient intake (protein, carbohydrates, fat) using established scientific formulas and recommendations. This page lists the source behind each calculation and recommendation shown in the app.

These values are estimates provided for informational and educational purposes. Constance is not a medical device and does not replace the advice of a healthcare professional. Consult a doctor or dietitian before starting any diet or exercise program, especially in case of a medical condition, injury, pregnancy or ongoing treatment.

1. Basal metabolic rate (resting calories)

Basal metabolic rate is estimated with the Mifflin-St Jeor equation: 10 × weight (kg) + 6.25 × height (cm) − 5 × age (years) + 5 (men) or − 161 (women). It is one of the most accurate predictive equations for the healthy general population.

Mifflin MD, St Jeor ST, Hill LA, Scott BJ, Daugherty SA, Koh YO. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr. 1990;51(2):241-247. — pubmed.ncbi.nlm.nih.gov/2305711

2. Total energy expenditure (maintenance calories)

Maintenance calories equal the basal metabolic rate multiplied by a physical activity level factor, adjusted to the training frequency you report. This approach follows international guidance on energy requirements.

FAO/WHO/UNU. Human energy requirements. Report of a Joint Expert Consultation, Rome, 2001. — fao.org/4/y5686e

EFSA Panel on Dietetic Products, Nutrition and Allergies. Scientific Opinion on Dietary Reference Values for energy. EFSA Journal. 2013;11(1):3005. — efsa.europa.eu

3. Calorie goal (deficit / surplus)

For fat loss, Constance applies a moderate deficit (around 15–20% below maintenance) to support gradual, sustainable loss. For muscle gain, a slight surplus (around 8%) is applied. The "maintenance" goal creates neither a deficit nor a surplus.

Helms ER, Aragon AA, Fitschen PJ. Evidence-based recommendations for natural bodybuilding contest preparation: nutrition and supplementation. J Int Soc Sports Nutr. 2014;11:20. — doi.org/10.1186/1550-2783-11-20

4. Protein intake

Constance targets about 1.8 g of protein per kg of body weight (up to 2.0 g/kg for muscle gain), in line with recommendations for physically active people.

Jäger R, Kerksick CM, Campbell BI, et al. International Society of Sports Nutrition Position Stand: protein and exercise. J Int Soc Sports Nutr. 2017;14:20. — doi.org/10.1186/s12970-017-0177-8

5. Fat and carbohydrates

Fat makes up about 27% of energy intake, within the recommended 20–35% range. Carbohydrates make up the remaining energy after protein and fat.

EFSA. Dietary Reference Values for nutrients — Summary report. EFSA Supporting publication 2017:e15121 (fat, carbohydrates). — efsa.europa.eu/dietary-reference-values

6. Body composition (body fat percentage)

The silhouette and body fat references used during onboarding are based on commonly accepted body fat percentage categories.

American Council on Exercise (ACE). Percent Body Fat Norms. — acefitness.org