Last reviewed: 2026-09-03 • Editorial Standards

Fermented Soy Ranked by Purine Content

Evidence-based comparison — data from USDA+ODS-NIH PURINE DATABASE Release 2 (March 2025)

Lowest Purine Fermented Soy

#1Miso White miso48.8 mg
#2miso56.1 mg
#3Miso Red miso63.5 mg
#4soybean, fermented (natto)113.9 mg
#5Fermented soybean (Natto)113.9 mg

Highest Purine Fermented Soy

#5Miso White miso48.8 mg
#4miso56.1 mg
#3Miso Red miso63.5 mg
#2Fermented soybean (Natto)113.9 mg
#1soybean, fermented (natto)113.9 mg

Category Average: 79.2 mg/100g

The average across 5 Fermented Soy foods with lab-measured data. Foods below this average are better-than-typical choices within this category.

How to Use This Ranking

The purine ranking is sorted from lowest to highest. Rank #1 is the lowest-purine food in the category. Foods in the top half (above median) should be consumed with more awareness of portion and frequency. The difference between adjacent ranks varies: in some categories, rank #5 and #10 might be only 10 mg apart; in others, the gap can be 100+ mg. Always check the actual milligram value, not just the position. Rankings do not account for fructose or alcohol — use individual food pages for a complete risk assessment.

ACR 2020 Guideline Context

The American College of Rheumatology recommends that gout patients focus on purine awareness rather than complete food group elimination. Within any category, there is a wide purine range. The goal is to shift toward lower-purine choices within categories you already eat, rather than eliminating entire food groups. This ranking helps you identify which specific items to prioritize and which to limit.

Japanese guidelines recommend under 400 mg of total dietary purines per day. Using this ranking, you can estimate how much of budget each food uses per typical serving.

How This Comparison Is Built

Every food in this comparison passes through a three-factor risk model that looks at purines, fructose, and alcohol independently. Purine values are sourced from the USDA+ODS-NIH PURINE DATABASE Release 2 (March 2025) and Kaneko et al. (Biol Pharm Bull 37(5):709-721, 2014, PMID: 24553148), fructose from USDA SR28. Verdicts apply ACR 2020 limits — Safe means under 50 mg purine and 2 g fructose with no alcohol; Moderate falls between; Avoid exceeds these or contains alcohol. Data quality tiers (T1/T2/T3) are listed on each food's detail page.

This comparison is provided for informational purposes only and does not constitute medical advice. Individual tolerance to purines and fructose varies. Consult a healthcare professional for personalized dietary guidance. Last reviewed: 2026-09-03.

Frequently Asked Questions

Is miso bad for gout?
Miso is a fermented soy product with moderate purine values — in our database, white miso lists about 48.8 mg/100g. Like other soy foods, miso's purines are plant forms that affect uric acid less than meat purines, and there is no strong evidence linking miso to higher gout risk. The caution is sodium — miso is high in salt, which matters if gout coexists with high blood pressure.
Is natto high in purines?
Natto is moderate in purines — about 113.9 mg/100g in our database — which is higher than most vegetables but still plant-based purines. Natto is a fermented soybean with a distinctive profile, and its purines behave more gently than animal purines. Portion matters, but natto is not a food most people with gout need to avoid.
Is fermented soy safe for gout?
Fermented soy foods like miso and natto carry moderate plant purines — 5 items in our database range from about 48.8 to 113.9 mg/100g. Plant purines affect uric acid less than meat and seafood purines, and soy foods are not linked to higher gout risk in population studies. The main cautions are sodium in miso and portion size in general.