Primary Data Sources
USDA and ODS-NIH Database for the Purine Content of Foods — Release 2.0 (March 2025)
Official source: USDA ARS · Purine Content of Foods. Release 2.0 covers 462 foods and 15 alcoholic beverages across 20 food groups, with HPLC-HRMS/MS verified measurements of all four purine bases (adenine, guanine, hypoxanthine, xanthine). Published March 2025.
This database was developed jointly by the USDA Agricultural Research Service and the NIH Office of Dietary Supplements. It is the most authoritative publicly available purine reference for U.S. foods.
Kaneko K, Aoyagi Y, Fukuuchi T, Inazawa K, Yamaoka N (2014)
This landmark study analyzed 270 foodstuffs using High-Performance Liquid Chromatography (HPLC) and categorized them into six purine risk classes. It is the most-cited purine reference in the gout medical literature and covers many foods common in Asian diets. The widely-referenced Japanese guideline of <400 mg/day dietary purine intake is derived from this work.
USDA SR28 Food Composition Tables
Fructose values on GoutFoodGuide are sourced from the USDA Standard Reference 28 (SR28) Food Composition Tables, the definitive reference for food nutrient composition in the United States.
Data Coverage
The USDA/ODS-NIH Release 2.0 database provides directly measured purine values for 462 foods. GoutFoodGuide extends coverage to over 1,400 foods by supplementing with purine data from Kaneko et al. (2014), USDA FoodData Central, and additional peer-reviewed literature. Foods with directly measured HPLC values from USDA/ODS-NIH are marked T1; foods with values derived from other published sources are marked T2 or T3 according to our quality tier system described below.
How Purine Is Measured
The gold standard for purine analysis is High-Performance Liquid Chromatography (HPLC). The process involves:
- The food sample is hydrolyzed with acid (trifluoroacetic acid and formic acid) at 90°C for 12 minutes, breaking down purine-containing compounds into their four constituent bases.
- The resulting solution is filtered and injected into an HPLC column.
- The four purine bases (adenine, guanine, hypoxanthine, xanthine) are separated based on their chemical properties and detected at 254 nm wavelength.
- Concentrations are calculated by comparing peak areas against known standard solutions.
- Total purine content = sum of all four base concentrations.
Quality Tiers (T1/T2/T3)
| Tier | Description | Reliability |
|---|---|---|
| T1 | Both purine and fructose individually lab-measured by HPLC for that specific food item | Highest |
| T2 | One dimension lab-measured; the other estimated from scientific consensus for similar foods | Good |
| T3 | Category-level estimate — not individually measured | Directional only |
Risk Assessment Methodology
Our three-dimensional risk engine evaluates:
- Purine content — Lower Risk: <50 mg/100g. Medium: 50-150 mg/100g. Higher Risk: >150 mg/100g
- Fructose content — Lower Risk: <2g/100g. Medium: 2-5g/100g. Higher Risk: >5g/100g
- Alcohol — Any measurable alcohol content triggers Higher Risk rating
The final verdict is the most restrictive of the three dimensions. A food lower in purines but high in fructose receives Higher Risk. This follows the ACR 2020 guideline principle that all three factors independently contribute to gout risk.
Licensing & Attribution
USDA FoodData Central: Data is in the public domain and published under CC0 1.0 Universal (CC0 1.0). No permission is needed for use; attribution is requested. Suggested citation: U.S. Department of Agriculture, Agricultural Research Service. FoodData Central, 2019. fdc.nal.usda.gov.
USDA & ODS-NIH Purine Database Release 2.0: Published by the U.S. Department of Agriculture and the NIH Office of Dietary Supplements as a U.S. government work, in the public domain. Documentation available at USDA ARS Purine Database Documentation (PDF, 2025).
Kaneko et al. 2014: Published article; data used with citation under academic fair use. DOI: 10.1248/bpb.b13-00967.