How the Grain Score is calculated.
A score is a starting point, not a verdict. Below is every input, every weight, and every assumption we make — in plain language. One methodology produces every score in the app — a food & drink engine, plus matched engines for beauty, supplements, feminine care, and household care — and when it changes, this page changes with it.
Last updated: July 14, 2026.
A —Two axes, per serving.
Nutrition quality — 60%
A Nutri-Score-style points system over the quantities in a realistic serving: energy, sugar, saturated fat, and sodium count against; fiber and protein count for. Added sugar is penalized in full; the intrinsic sugar in whole foods (fruit, plain dairy) is discounted. Drinks are judged on stricter beverage thresholds.
Ingredient quality — 40%
Every ingredient on the label is checked against evidence tiers — hazardous (−25), moderate (−10), limited (−4), plus a separate refined-oil tier — with a clean-ingredient bonus (+3 each, capped at +15). Details in section C.
Processing — a deduction, not a component
Processing is no longer a weighted component of the score. A NOVA group is still derived from the ingredient list and used two ways: as a one-way deduction (−8 for ultra-processed NOVA 4, −3 for NOVA 3, waived for clean-ingredient products) and as a gate inside several of the ceilings in section D. It can lower a score; it can never lift one.
Personal overlay
Your allergies, ingredients you avoid, and preferred certifications are layered on top of the base score on your device. The base score is the same for everyone; the overlay is yours.
The serving basis. Scores are computed per serving — the amount you actually eat — not per 100g. A declared label serving always wins; when a label carries no usable serving (or a placeholder "100g"), we fall back to an FDA RACC-derived typical serving for the category and mark the score as based on an estimated serving. Serving-independent density checks (section D) stop a tiny declared serving from hiding a sugar or fat bomb. Drinks are scored on a per-serving beverage curve with a per-100ml sugar-density guard. When a product has no nutrition data at all, the weights shift to 10/90 onto ingredients and the score is flagged provisional.
B —The formula.
base = nutrition × 0.60 + ingredients × 0.40 (per serving)
(no nutrition data: 0.10 / 0.90, flagged provisional)
then quantitative ceilings checked (added sugar, sodium,
saturated fat, density, alcohol — section D)
then processing deduction (NOVA 4 → −8, NOVA 3 → −3,
waived for clean-ingredient products)
floors clean-ingredient products ........ never below 55
simple whole foods ............... never below 78
Whole foods get protected on the nutrition axis too: a NOVA-1, additive-free food with three or fewer ingredients (plain oats, nuts, meat, fish) is floored at a sound nutrition value rather than punished by packaged-food math for its natural fat or calorie density, and clean single-ingredient drinks like 100% juice or plain milk keep their intrinsic-sugar protection on the food axis — though juice, once judged as a drink, is still subject to the free-sugar drink caps in section D.
C —The ingredient tiers.
Hazardous — −25 each, caps the ingredient component at 35
Direct regulatory action, strong evidence at dietary relevance, or a deliberate clean-label avoid: sodium/potassium nitrite and nitrate, potassium bromate, propylparaben, butylparaben, ethoxyquin, titanium dioxide, brominated vegetable oil, azodicarbonamide, partially hydrogenated oils, sulfite preservatives (sodium/potassium/calcium sulfites and metabisulfites, sulfur dioxide), diacetyl, olestra, banned supplement stimulants (DMAA, ephedra and similar), Red 3 (FDA revoked food use, January 2025), the named synthetic dyes (Red 40, Yellow 5 & 6, Blue 1 & 2, Green 3), and artificial colors and flavors. The dyes and artificial flavors are a precautionary clean-label stance backed by real regulatory momentum (EU child-attention warning labels; several dyes under FDA review) — not a proven-toxicity claim.
Refined seed & tropical oils — −25 each, same ingredient-component cap
Refined vegetable oils (canola, soybean, sunflower, corn, safflower, cottonseed, rapeseed) and palm/palm-kernel oil carry −25 and cap the ingredient component at 35, like the hazardous tier. Organic, expeller-pressed, or cold-pressed forms drop to a mild −5. We're explicit about what this is: no regulator classifies refined vegetable oils as hazardous, and some evidence cuts the other way. Flagging them is a deliberate, cautious Grain stance — shown to you as a stance, not as settled science.
Moderate — −10 each
Regulatory scrutiny or significant published evidence at dietary dose: high-fructose corn syrup, sodium benzoate, aspartame and other high-intensity sweeteners (acesulfame, sucralose, saccharin), BHA, BHT, TBHQ, carrageenan, polysorbates, PGPR, erythritol, sodium and potassium phosphate additives (phosphoric acid included), Class III/IV caramel color, and maltodextrin. Stacking two or more phosphate additives adds an escalating cumulative-load penalty and triggers the hazardous-tier cap.
Limited — −4 each
Recognized as safe but highly processed, or a concern only at high intake or for sensitive groups: dextrose, corn syrup, MSG, yeast extract, mono- and diglycerides, potassium sorbate, vanillin, calcium phosphates, and generic (Class I/II) caramel color. An undisclosed compound ingredient (a bare "BBQ sauce" with no sub-list) takes a small penalty too, since its composition can't be verified.
Clean bonus — +3 each, capped at +15
Genuinely health-positive ingredients, not basic staples: olive and avocado oil, rolled oats, quinoa, lentils, chickpeas, chia and flax seed, nut butters, cocoa, collagen, whey and pea protein.
Tier placement tracks regulator evidence — FDA, EFSA, IARC, JECFA — and is re-graded as that evidence evolves. A 2026 science audit moved aspartame and the other high-intensity sweeteners, BHA/BHT/TBHQ, carrageenan, and polysorbates from hazardous down to moderate: a hazard label at any dose is not the same as risk at dietary dose. The named synthetic dyes and artificial flavors were subsequently placed back in the hazardous tier as a deliberate clean-label decision — with the precautionary framing above.
Some common ingredients are deliberately not penalized at all — citric acid, xanthan gum, modified food starch, soy lecithin, natural flavors — because the evidence doesn't support a deduction. EU-style labels are normalized before scoring: an ingredient panel that says "E621" scores exactly the same as one that spells out "monosodium glutamate."
D —Floors and ceilings.
Whole-food floors
Clean-ingredient products never score below 55. Simple whole foods — three or fewer ingredients, zero flagged additives, like plain oats, rice, or frozen fruit — never score below 78.
Added-sugar ceilings (per serving)
Added sugar ≥30g caps the final score at 35; ≥20g at 45; ≥12g at 60. Intrinsic sugar in whole foods is protected — real fruit isn't punished like soda. For drinks, total sugar ≥20g per serving caps at 35: once juiced, fruit sugar is free sugar, so a glass of 100% juice is capped while plain milk is not.
Sodium and saturated-fat ceilings (per serving)
Sodium ≥1500mg caps at 45 (≥1000mg at 60, ≥700mg at 75). Saturated fat ≥15g caps at 50 (≥10g at 65); whole-food fats with a clean ingredient list (nuts, dark chocolate, cheese) get relaxed thresholds (≥24g → 62, ≥17g → 78) so a cleaner option can still rank meaningfully higher.
Density checks — a small serving can't hide it
Serving-independent density rules backstop the per-serving basis. If saturated fat supplies ≥20% of calories in a non-whole-food product, the score caps at 60 (≥35% → 50); a product that is nearly all saturated-heavy fat (butter, ghee) caps at 60 even when clean. Heavily salted-for-the-calories products (≥2mg sodium per kcal) cap at 75. On the nutrition axis, calorie-dense fried snacks (≥420 kcal/100g with flagged oils) and ultra-processed confectionery (≥30% sugar by weight) have their nutrition component floored down regardless of how small the declared serving is.
Concentrated seasonings — judged on real exposure
Salt-functional condiments used in small regulated amounts (miso, soy sauce, mustard, bouillon, yeast extract spreads) are judged on the sodium in their actual per-serving amount against a %-of-daily-value ladder, not on per-100g density — 100g of miso is nobody's serving. This is not a free pass: a genuinely high-sodium serving (a ramen seasoning packet) still maxes the ladder and scores accordingly.
Avoid-tier ingredients keep junk out of the healthy band
When a restrictive ceiling fires, ingredient cleanliness can lift the capped score by at most +12 — and never above 49 — so within a capped category (candy vs. candy) the cleanest option still ranks first without ever reading "healthy".
Alcohol
Alcohol and tobacco products are not presented as rated products in the app. As a backstop, the engine structurally caps any alcoholic beverage at 40 — alcohol is a WHO Group 1 carcinogen with no established safe level. Precautionary, not absolutist.
Honest uncertainty
A product with no nutrition data caps at 65 unless it's an authoritative whole food, and a product with neither ingredients nor nutrition gets a flat provisional 50 — both flagged "provisional" in the app. A score computed from thin data is never presented with full confidence.
Two ceilings you may remember are gone: the Nutri-Score letter-grade ceilings (E → 35, D → 60) and the blanket NOVA-4 ultra-processed ceiling (max 75) were removed in July 2026. The external grade duplicated what our own layers already measure, and its coarse bands kept overriding the surgical caps above — a clean 70% dark chocolate was being crushed to 44 by a grade computed on total sugar. The quantitative per-serving and density ceilings above, plus the ingredient tiers, now do that job with more precision.
E —Beyond food: the other four engines.
Beauty & personal care
Ingredient safety starts at 100 and is reduced by evidence-tiered penalties (Tier 1 avoid, Tier 2 caution), weighted by exposure: rinse-off products (soap, shampoo) are relaxed to half the penalty of leave-on products, and comedogenic concerns apply to leave-on only. Beneficial actives earn credit. Multiple AI-flagged caution ingredients cap the score on a graduated ladder (3 → 80, 4 → 74, 5 → 68). Loose, inhalable talc is treated as a top-tier precaution; pressed talc is not — framing is always precautionary, never a proven-harm claim.
Supplements
Judged on formulation, purity, and testing: clean, dose-disclosed, third-party-tested formulas (NSF, USP) score high; synthetic fillers, dyes, and titanium dioxide pull scores down. Disclosed grouped blends ("probiotic blend" with named components) take only a small transparency ding; literal "proprietary blends" take a larger one and forfeit the clean-formulation bonus. A pill-form product whose label lists no excipients at all is treated as incomplete data, not as verified-clean.
Feminine care
The beauty skeleton with a mucosal-exposure axis: internal products (tampons, cups, douches) carry a ×1.5 penalty multiplier, and fragrance in an internal product is a top-tier concern. Douches carry a structural score ceiling of 40, reflecting ACOG/CDC guidance against douching — a product-class precaution, never a per-ingredient harm claim. Products with no ingredient/material disclosure (most cups, discs, period underwear) get an honest provisional 50 rather than a phantom score. Where evidence doesn't support a penalty (e.g. trace-theory concerns), Grain shows an informational note instead of docking the score.
Household care
The same skeleton with an exposure-route axis (sprays and air care ×1.5 for inhalation, rinse-off ×0.6, leave-on residue ×1.1) and a disclosure-honesty axis: cleaning brands aren't required to disclose formulas, so "this brand won't tell you" is itself a finding — a label listing only functional classes ("surfactants, preservative") caps at 52 and is flagged provisional. Good disclosure can never rescue a hazard-capped score. Every hazard flag cites a primary authority (EU CLP/ECHA, AOEC asthmagen codes, IARC/NTP, EPA Safer Choice).
F —A worked example.
Sweetened corn-flake cereal (illustrative)
Assumed inputs, per 40g serving: 150 kcal · 13g added sugar · 190mg sodium · 1g fiber · contains BHT · derives NOVA 4
G —Sources and verification.
Cited, or honestly empty
Ingredient risk entries link to primary sources in the app — EFSA, FDA, IARC, NTP, WHO. Where no honest authority source exists, the citation list stays empty rather than padded.
Region-aware
Six regulatory regions — US, EU, UK & Ireland, Canada, Australia & New Zealand, Switzerland — with the matching food authorities (FDA, EFSA, FSA, Health Canada, FSANZ, FSVO) built into Grain's AI context. Five languages.
Grounded AI
AI product answers are grounded in live web search, and a "real" product that returns zero grounding citations is treated as a red flag — not shipped as fact. Responses are AI-generated and may not always be accurate.
Vision-checked images
Product photos pass an automated vision quality gate before they're shown to you.
H —What we don't know.
Nutrition science is not settled. Regulators disagree. Formulations change without notice. The Grain Score is our best attempt at synthesis, built from public data and AI assistance — it is an estimate, and it will be wrong sometimes. When an ingredient is genuinely contested — seed oils are the clearest example — we tell you it's a stance, not settled science. And when the formula changes, this page changes with it.