Methodology & Data Sources

What PlainPetFood Covers

PlainPetFood is a comprehensive food safety reference for pet owners, documenting which human foods are safe, potentially harmful, or toxic for dogs, cats, and other common household pets. Each food entry includes a safety level, recommended portion guidance, preparation notes, potential health benefits, known risks, and symptoms to watch for if a pet consumes something harmful.

Data Sources

Our food safety data is compiled from authoritative veterinary and animal nutrition sources:

• ASPCA Animal Poison Control Center: The ASPCA maintains the most comprehensive toxic and non-toxic plant and food lists for companion animals, based on decades of poison control case data.
• Merck Veterinary Manual: The standard veterinary reference providing toxicology information, including dose-dependent toxicity data for common food items.
• Peer-reviewed veterinary literature: Published research on animal nutrition, food toxicology, and clinical case reports from veterinary journals.
• AVMA and veterinary university resources: Guidance from the American Veterinary Medical Association and veterinary school extension programs, including the Cornell Feline Health Center, Ohio State University College of Veterinary Medicine, and University of Illinois College of Veterinary Medicine.

Safety Level Classification

Each food-pet combination is assigned one of four safety levels:

• Safe: The food is generally safe for this pet species when served in appropriate portions and properly prepared. No known toxicity concerns at normal serving sizes.
• Caution: The food can be given in small amounts or with specific preparation requirements, but carries some risk if overfed or improperly prepared. Portion control and preparation guidance are especially important.
• Unsafe: The food poses meaningful health risks and should generally be avoided. May cause gastrointestinal distress, nutritional imbalances, or other health issues.
• Toxic: The food contains compounds that are toxic to this pet species and should never be given. Even small amounts may cause serious illness or be life-threatening. Common examples include chocolate, grapes, onions, and xylitol for dogs.

Where counts fold Toxic into Unsafe

Individual food pages always show the exact level of the four above. Summary counts do not: every rolled-up figure on this site - the homepage totals, the dog and cat overview cards, and the per-category tallies - counts Toxic inside Unsafe and is labelled "unsafe / toxic" wherever it appears. The fold is applied to every summary equally, so no two figures on a page are counted on different populations, and each species' three buckets always sum to the full number of foods rated for that species. If you want toxic-only figures, the toxic-foods rankings and each food's own page give them unfolded.

Safety levels are assigned conservatively. When veterinary sources disagree or when toxicity is dose-dependent with a narrow safety margin, we err toward a more cautious classification.

Research and Curation Process

Our database is built through a structured research process for each food item:

1. Identify the food item and determine which pet species require separate safety assessments (dogs, cats, and others may metabolize foods differently)
2. Research the food's safety profile across multiple veterinary sources, noting any toxic compounds, dose-dependent effects, and species-specific differences
3. Document safe preparation methods (e.g., cooked vs. raw, seeds removed, skin peeled) based on veterinary guidance
4. Establish appropriate portion guidelines relative to pet body weight where available
5. Catalog known benefits (nutritional value) and risks (choking hazards, digestive issues, toxic compounds)
6. Document symptoms of adverse reactions so pet owners know what to watch for

No safety data is extrapolated from human nutrition data. The references above are what our editors consult; they are not a per-record source. Foods that the FDA or the ASPCA Animal Poison Control Center explicitly names as dangerous to pets carry that citation on the food's page, and every other rating is our own editorial judgement, labelled as such where it appears. We would rather show you which claims we can attribute than imply that all of them are.

Update Schedule

We expand our food database on a rolling basis, adding new food items and updating existing entries as new veterinary research becomes available. When veterinary organizations issue updated guidance on a specific food (such as reclassifying a food's safety status), we update our database accordingly. Each entry reflects the most current veterinary consensus at the time of our last review.

Corpus placement (#N of M)

Food and category pages show where each entity sits in the PlainPetFood corpus, not just the entity's own safety verdict. Placement uses two ladders that can diverge, so a single "#N of M" never pretends one metric is the whole story.

• Foods - dog hazard band: rank among foods with a dog safety row, ordered by band severity (toxic > unsafe > caution > safe). Highest-hazard foods lead this ladder.
• Foods - dog documentation depth: rank by the combined character length of benefits, risks, symptoms, and notes on the dog safety row. A mild caution can still lead this ladder when its write-up is the longest in the corpus.
• Categories - food inventory: rank by number of foods in the category (largest inventory = #1).
• Categories - dog hazard count: rank by count of dog-side unsafe+toxic ratings. Inventory and hazard count diverge: seafood can be large with few hazard ratings; sweets can reverse that pattern.

Ties break by slug. Ranks are recomputed from the live SQLite tables on each request (cached in-process). They are inventory placement inside this corpus, not a veterinary diagnosis or a claim that one food is "worse" than another for every pet.

How the cross-species safety score is computed

Each food page shows one 0-100 score and an A+ to F grade that combines the dog verdict and the cat verdict for that food. It is editorial guidance, not a veterinary diagnosis: the inputs are our own four-level ratings, and only 16 of 160 dog ratings and 16 of 160 cat ratings carry an FDA or ASPCA citation. Every other rating is PlainPetFood's judgement, labelled as such on the food's page. The steps below are everything the score uses.

Step 1: turn each safety level into a number

The four levels are categories, not measurements, so the mapping is a scale we chose, not federal data: safe = 100, caution = 65, unsafe = 30, toxic = 0.

Step 2: rank that number against the other rated foods

For each species we take those numbers across every food rated for that species (160 for dogs, 160 for cats) and compute the 10th, 25th, 50th, 75th and 90th percentiles. A food's number is then placed on that percentile scale by linear interpolation between the two nearest benchmarks.

Because there are only four levels, many foods tie, so the percentile positions are coarse. In practice each species gives a food one of four scores:

Step 3: combine the species

The overall score is the weighted average of the two species scores, rounded to a whole number. Weights: dogs 50%, cats 50%. If a food has no rating for one species, that species is dropped and the other one is reweighted to 100%, so a missing rating never lowers the score. If neither species has a rating, no score is shown.

Step 4: read the grade

A+ 90-100, A 85-89, A- 80-84, B+ 75-79, B 70-74, B- 65-69, C+ 60-64, C 55-59, C- 50-54, D 40-49, F 0-39.

Limitations

• Individual pets may have allergies, sensitivities, or health conditions that make otherwise safe foods inappropriate for them. Always consult your veterinarian about your specific pet's dietary needs.
• Portion guidance is general, appropriate amounts vary based on pet size, breed, age, and overall health.
• Toxicity can be dose-dependent. A food classified as "caution" may be harmless in tiny amounts but dangerous in larger quantities.
• Our database covers common human foods; commercial pet food ingredients and supplements are not evaluated.
• New research may change the safety classification of specific foods. Always check with your veterinarian for the most current guidance.

Emergency Information

If your pet has eaten something potentially toxic, contact your veterinarian or the ASPCA Animal Poison Control Center at (888) 426-4435 immediately. Do not wait for symptoms to appear.

Reuse and Citation

PlainPetFood's food-safety entries are freely citable and linkable, please link back to the specific food page rather than reproducing the safety classification elsewhere, since entries are updated as veterinary guidance changes. Unlike a government-data portal, PlainPetFood doesn't redistribute a single licensed dataset, each entry is our own synthesis of the cited veterinary sources (ASPCA, Merck Veterinary Manual, peer-reviewed literature, and veterinary school resources), and that synthesis carries its own copyright. We don't offer bulk data licensing or an API at this time.

Contact

Questions about our methodology or data? Contact us - we welcome feedback and corrections.