Transparency

Methodology & data sources

Calories, formulas and coaching recommendations are only as good as their sources. Here's where Myron's numbers come from — and where their limits lie.

Nutrition data

The calorie tables are based on the Bundeslebensmittelschlüssel (BLS) 4.0 from the Max Rubner Institute — Germany's official nutrient database (license: CC BY 4.0). Values are per 100 g; portion sizes are editorially added. In the app, generic foods come from the official database of your content language — USDA FoodData Central (English, public domain), Ciqual 2025 (French, ANSES, Licence Ouverte/Etalab 2.0), Tabelle di composizione degli alimenti 2019 (Italian, CREA) — and barcode data from Open Food Facts covers packaged products.

Calorie needs: the formulas

The calorie calculator uses the Mifflin-St Jeor equation (1990) for basal metabolic rate: 10 × weight (kg) + 6.25 × height (cm) − 5 × age ± sex constant. Comparison studies rate it the most reliable of the common estimation formulas, and it is recommended by the Academy of Nutrition and Dietetics, among others. Multiplied by an activity factor (PAL 1.2–1.9) it yields total daily energy expenditure; goal adjustments are converted at ~7,700 kcal per kilogram of body mass. The macro recommendation: protein 1.8–2.4 g/kg depending on goal, fat 0.9 g/kg as a baseline, the rest carbohydrates.

Important: every formula estimates. That's why the Myron app doesn't stop at the estimate — it continuously back-calculates your actual expenditure from the past weeks, using logged nutrition and your weight trend. After two to three weeks of tracking, this adaptive value replaces the formula.

Exercise directory

The exercise directory is based on an open exercise catalog, editorially translated into German for Myron and extended with muscle-group mapping and step-by-step instructions.

The coach: evidence over gut feeling

The Myron coach's recommendations follow an evidence-based playbook: every rule is backed by sources (meta-analyses and position stands of sports-science bodies) and is checked against new literature every quarter. When the evidence changes, the playbook changes — transparently documented.

Limits

All values are approximations: individual deviations of ±10 % in energy expenditure are normal. Myron is not a medical product and does not replace medical or dietetic advice — with pre-existing conditions, pregnancy or eating disorders, nutrition planning belongs in professional hands.

Sources: Mifflin MD, St Jeor ST et al. (1990), Am J Clin Nutr 51(2) · Max Rubner Institute (2025): Bundeslebensmittelschlüssel 4.0 (CC BY 4.0) · USDA FoodData Central (public domain) · ANSES (2025): Table Ciqual (Etalab 2.0) · CREA: Tabelle di composizione degli alimenti, Aggiornamento 2019.