What does a score of 93 mean?

93 out of 100 places tap water in the "excellent" band. Among the lower-risk choices for most people with gout, and often carries protective nutrients. Scores rank foods against each other on average across a population. They are not a personal risk level.

What portion is the score based on?

Nutrition figures are given per 100 g, and the scoring applies a serving-size adjustment based on this food's typical portion: 1 cup (240 g). Eating substantially more or less than that shifts the real-world effect accordingly.

How confident is this score?

Based on direct, measured purine data for this food. This is one of the better-supported scores in the database.

Can I eat tap water if I have gout?

That is a question for you and your clinician. This page ranks foods on published population-average evidence; it does not account for your urate level, kidney function, medications or overall eating pattern.

Beverage

Tap water

USDA description: Water, tap

How tap water scores for gout, what moved that score, and the nutrition and portions behind it.

Food Index score

Tap waterExcellent

0100

Based on measured purine data

What moved this score
Starting score	100
Nutrient Gaps	-10
Hydration	+3
Sodium	-0.1
Magnesium	+0.1
Final score	93

Flare risk (acute)100

Long-term (chronic)90

Tap water scores 93 out of 100 and sits in the excellent band. Among the lower-risk choices for most people with gout, and often carries protective nutrients.

Penalties took 10.1 points off a starting score of 100, and protective factors added 3.1 back. Every factor is listed in full below.

Scores run 0–100, where higher means more gout-friendly on average. They reflect relative ranking across foods, not a personal risk level. The same food can suit one person and not another, so use the score as a starting point for a conversation with your clinician.

Compare with another foodMore tap water How scoring works

The underlying data

Nutrition and portions

Nutrition Facts

Amounts per 100 g

Typical serving240 g

Calories0

Total Fat0 g
Saturated Fat0 g
Sodium4 mg
Dietary Fiber0 g
Total Sugars0 g
Protein0 g

Calcium3 mg
Iron0 mg
Magnesium1 mg
Vitamin C0 mg
Folate0 ug

Water99.9 g
Alcohol0 g
Omega-3 EPA0 g
Omega-3 DHA0 g

Common portions

1 cuptypical240 g
1 fl oz30 g
1 ice cube20 g
1 cup ice110 g
1 bottle (16.9 fl oz) filled with tap water507 g
1 bottle (24 fl oz) filled with tap water720 g
Guideline amount if from a water fountain60 g
Quantity not specified360 g

Where the purine figure comes from

The purine content of this food has been measured directly in published laboratory studies, so the score uses that measured figure.

We rate this a high confidence estimate.

How purines affect the score →

Nutrition values from the USDA FoodData Central database.

Scoring rationale

Every factor, in full

Each row shows the points a factor moved, what drove it, and the studies behind its weight.

PointsFactorAffects

-10
Nutrient GapsLong-term
Provides meaningful amounts of only 0 of the 5 protective nutrient groups (vitamin C, fiber, omega-3, magnesium and folate).
Evidence: Choi HK 2009, Arch Intern Med · Juraschek SP 2016, Arthritis Rheumatol · Zhang M 2019, Arthritis Rheumatol
Long-term
+3
HydrationFlare risk
99.9 g of water per 100 g. Staying hydrated helps the kidneys clear urate.
Evidence: Neogi T 2014, Am J Epidemiol
Flare risk
-0.1
SodiumLong-term
4 mg of sodium per 100 g, scaled 2.4x for the typical portion.
Evidence: FitzGerald JD 2020, Arthritis Care Res
Long-term
+0.1
MagnesiumLong-term
1 mg of magnesium per 100 g, scaled 2.4x for the typical portion.
Evidence: Li X 2015, BMJ
Long-term

Keep looking

Similar foods in tap water

Water, NFS

Tap water · Excellent

Common questions

About tap water

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Each score lists the factors that moved it, the portion it assumes, and the studies behind each factor's weight.

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