NUTRITION ANALYSIS
Nutrient Scoring Models
Fuel Lens offers two approaches to nutrient-density scoring. Both compare foods per 100 kcal; interpret each score together with its data coverage.
Nutrient Rich Food Index (NRF): the scientific standard
The Nutrient Rich Food Index (NRF) scores nutrients to encourage against nutrients to limit. The classic NRF 9.3 combines nine positive nutrients—protein, fiber, vitamins A, C and E, calcium, iron, magnesium and potassium—with three nutrients to limit: saturated fat, added sugars and sodium. It measures nutrient density rather than calories alone. Drewnowski (2010) describes its use in identifying nutritious, affordable foods.
Research variants include NRF 6.3, NRF 9.3, NRF 11.3 and NRF 15.3: the numbers identify the positive and limited nutrient counts. Fuel Lens offers NRF 9.3 alongside adapted and expanded profiles up to NRF 26.5; its nutrient sets and normalized display are specific to the app.
Read the Nutrient Rich Food Index (NRF) guide: variants, formula and research →
Custom model: soft caps and incomplete data
The Custom model uses an exponential soft cap and reweights known nutrients when data is missing. Read its dedicated guide for the formula, nutrient weights, and reliability.
Compare foods in Fuel Lens ↗ · Scoring settings
Related guides
Continue with these connected Fuel Lens guides.
- Nutrient Rich Food Index (NRF)Explore the Nutrient Rich Food Index (NRF), classic NRF 9.3, research variants, and Fuel Lens's scoring formula.
- Custom modelLearn how soft caps, nutrient weights, and missing data shape the Custom Exponential score.
- Compare FoodsCompare foods side by side using nutrient-density scoring.