The Claim

In overweight, non-smoking adults aged 40–65, commercially available saliva test strips from Berkeley and Neogenesis show a moderate to strong correlation with laboratory-measured salivary nitrite levels (r = 0.76 and r = 0.59, respectively) and no significant correlation with serum nitrite or nitrate concentrations, indicating that these test strips are valid only as surrogates for oral nitrite and not for systemic nitric oxide bioavailability.

Source: Validation of two Point-of-care Tests against Standard Lab Measures of NO in Saliva and in Serum

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
35score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Correlation
1 study reviewed
In plain English

In overweight, non-smoking adults aged 40–65, saliva test strips from Berkeley and Neogenesis reliably measure nitrite levels in saliva but do not reflect nitrite or nitrate levels in the blood, meaning they cannot be used to assess systemic nitric oxide activity.

See the scientific wording

In overweight, non-smoking adults aged 40–65, commercially available saliva test strips (Berkeley and Neogenesis) show a moderate to strong correlation with laboratory-measured salivary nitrite levels (r = 0.76 and r = 0.59, respectively), but no significant correlation with serum nitrite or nitrate, indicating they are valid only as surrogates for oral nitrite, not systemic nitric oxide bioavailability.

Why this might work

Dietary nitrate enters the bloodstream, gets pulled into saliva by glands in the mouth, and is turned into nitrite by bacteria on the tongue. This nitrite stays in the mouth and does not enter the blood in significant amounts, so tests that measure nitrite in saliva only reflect what is happening in the mouth, not in the rest of the body.

Verified mechanismbased on 1 study

What the research says

1 study

  1. Study: Validation of two Point-of-care Tests against Standard Lab Measures of NO in Saliva and in Serum

    These cheap saliva strips can tell you how much nitrite is in your spit, but they can't tell you what's happening in your blood. So they're useful for your mouth, not your heart health.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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