Stop guessing at the grocery store

The problem

Someone newly diagnosed with IBS is handed a low-FODMAP guide by their dietitian and then stands in the cereal aisle in front of forty boxes. Which are safe? Which hide garlic powder or inulin behind “natural flavors”? Generic nutrition apps grade food for an average person; the person in the aisle is not average, and the ingredients that matter to them are specific and easy to miss.

What we built

FoodGrader grades products against the person, not the population. Scan a barcode for verified data from a database of 5.6 million products, or take a photo when there is no barcode. The app returns a grade from A to F, personalized to the person’s plan — low-FODMAP, allergens, family profiles, diet goals — with a plain-English explanation of what drove the grade. FODMAP-aware grading is the core: ingredient-level flags for high-FODMAP triggers, including the hidden ones, that can be switched on with one tap in the profile.

How it works

Two ways in, one answer out. Barcode scans draw on verified product data; photo scans use vision AI to read the label. A proprietary grading algorithm scores fit, nutrition and ingredient quality against the person’s profile and produces both the letter and the reasons. FODMAP flagging is a best-effort check against published guidance and is labeled as such in the app.

Design decisions

Grade the fit, not the food. The same product can be an A for one person and a D for another. Personalization is the product, and the grade is meaningless without the profile behind it.

Ingredient-level, not category-level. “Contains onion” is a category warning. “Onion powder, listed fourth” is something a person can act on. The app flags at the level people actually read.

Always show why. Every grade carries its explanation. A black-box score would be faster to build and useless to trust.

Say when it is best-effort. FODMAP content is not printed on labels; it is inferred from ingredients. The app says so, plainly, rather than implying certainty it does not have.

Positioned for one audience. FoodGrader handles allergens and general diet goals, but it is built around, and marketed to, people managing IBS. A focused promise beats a broad one.

Outcome

FoodGrader is live on the App Store with a 4.8-star rating and a 5.6-million-product catalog, and has been repositioned from general nutrition to FODMAP and IBS, where the need is sharpest and the product is strongest.

What we learned

Repositioning a shipped product is a real lever. FoodGrader began as a general “personalized nutrition” app; the same capability, framed for a specific group with a specific problem, is a far clearer product to explain, find and recommend. Focus is a feature.

What this means for your project

If your users need to decide whether this item fits their rules — a policy, a specification, a diet, a compliance requirement — the pattern is the same: structured data where it exists, vision where it does not, a personal rulebook in the middle, and a grade that explains itself.