Methodology
Our Sources & Methodology
How Verdik approaches nutrition information.
Where our nutrient data comes from
Food composition data is sourced from USDA FoodData Central, the U.S. Department of Agriculture's reference database for food and nutrient information.
Reference Daily Intake (RDA) values are sourced from the NIH Office of Dietary Supplements and the FDA's Daily Values reference.
Health information about nutrients — functions, deficiency signs, and interactions — is synthesized from NIH ODS fact sheets and peer-reviewed nutrition literature.
How the Claim Checker works
The Claim Checker uses Claude, an AI model from Anthropic, to evaluate nutrition and health claims.
The system prompts Claude to bias toward peer-reviewed research from journals including Cochrane, BMJ, NEJM, AJCN, JAMA, and The Lancet, and government health agencies including NIH, USDA, FDA, CDC, and WHO.
The model evaluates claims for evidence strength, considers dose and population context, and flags uncertainty where the science is unsettled.
Verdik retrieves peer-reviewed studies from PubMed for each claim and grounds the verdict in them. Every citation shown is checked against the National Library of Medicine's records — a citation that cannot be verified as a real PubMed record is discarded, never shown. Each verified citation is also labeled with its stance toward the claim (supports, contradicts, or neutral), and counter-evidence is displayed rather than hidden.
The verdict scale
Every claim receives one of five verdicts. For structured data (schema.org ClaimReview), each verdict maps to a fixed numeric rating from 1 (the claim is contradicted by the evidence) to 5 (the claim is supported by the evidence). The mapping never varies by claim:
| Verdict | Rating | Meaning |
|---|---|---|
| Supported by Evidence | 5 | Peer-reviewed research consistently backs the claim. |
| Partially True | 4 | True in part — with meaningful caveats about dose, population, or context. |
| No Evidence | 3 | Unsubstantiated: no solid research supports it, and none clearly disproves it. |
| Misleading | 2 | Contains a kernel of truth presented in a way the evidence doesn't support. |
| Debunked | 1 | Peer-reviewed research contradicts the claim. |
Verdicts published at www.verdik.co/claims additionally pass a curation gate before appearing: every citation must verify against PubMed, at least two verified citations must align with the verdict, and any stance conflicts must be resolved. Where available, a confidence level (High, Moderate, Low) reflects how settled the underlying research is.
Our evidence rating philosophy
Verdik distinguishes between strong consensus (e.g., "Fiber supports digestive health"), emerging evidence (e.g., specific gut microbiome interventions), and weak or unsupported claims (e.g., "Detox teas cleanse the liver").
Not medical advice
Verdik provides educational information about nutrition and food. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider for personalized guidance about your diet, supplements, or medical conditions.
Questions or feedback
Reach us at verdikapp@gmail.com.