Sources & References
Last updated: June 2026
Our content aims to reflect the consensus of recognised health and sports-nutrition authorities and peer-reviewed research. Below are the standing bodies and validated equations we rely on. Individual articles may cite additional, more specific sources inline.
Health & nutrition authorities
- National Institutes of Health (NIH), Government biomedical research and dietary reference data.
- International Society of Sports Nutrition (ISSN), Position stands on protein, creatine, nutrient timing, and body composition.
- British Dietetic Association (BDA), Evidence-based dietetic guidance and food fact sheets.
- Academy of Nutrition and Dietetics, Professional dietetics positions and consumer guidance.
- World Health Organization (WHO), Global guidance on diet, physical activity, and BMI classification.
- NHS (UK), Public health guidance on diet, weight, and physical activity.
- Examine.com, Independent analysis of nutrition and supplement research.
- PubMed / peer-reviewed literature, Primary research underpinning specific claims.
Equations & methods
- Mifflin-St Jeor equation, Primary BMR estimate used across our calculators.
- Harris-Benedict equation, Alternative BMR/TDEE reference.
- US Navy circumference method, Body-fat percentage estimate from tape measurements.
- WHO BMI classification, Underweight / normal / overweight / obese thresholds.
The exact formulas and assumptions are documented on our Calculator Methodology page.
A note on evidence
Nutrition science is rarely settled. Where the evidence is strong we state conclusions plainly; where it is mixed or emerging, we say so rather than overstating certainty. If you believe we have misrepresented a source, please contact us.