The Study
Validation of two Point-of-care Tests against Standard Lab Measures of NO in Saliva and in Serum
This study checked if two cheap saliva strips give the same results as fancy lab tests for one chemical in spit. They found the strips match the lab for spit chemicals, but not for chemicals in blood. It doesn't tell us if the strips can tell if someone is healthy or sick — just if they match spit measurements.
Analysis score
Maximum 44 for a cross-sectional study.
Where the score came from
These cheap saliva strips change color to show nitrite levels in your mouth, but they can't tell you how much nitric oxide is in your blood.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 535 / 100
Quality score
Snapshots of a population at a single point in time, or descriptions of small groups. Can identify correlations and prevalence, but cannot determine cause and effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1No — high saliva nitrite comes from food and mouth bacteria, not from your blood vessels making nitric oxide, so the strips don't reflect heart or blood vessel health.
- 2Saliva nitrite: 62.1 µM; serum nitrite: 1.7 µM.
- 3Berkeley strip matches lab saliva nitrite with r=0.76; Neogenesis with r=0.59.
- 4Neither matches blood nitrite or nitrate.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Nitric oxide : biology and chemistry
Year
2017
Authors
Ashwin Modi, E. Morou-Bermúdez, José L Vergara, R. Patel, Alexandria Nichols, K. Joshipura
Related Content
Claims (6)
In overweight, non-smoking adults aged 40–65, nitrite levels in saliva are much higher than nitrite levels in blood, meaning saliva cannot be used to measure nitric oxide activity in the bloodstream.
In overweight, non-smoking adults aged 40–65, the Berkeley saliva test strip measures salivary nitrite levels more closely to laboratory results than the Neogenesis strip.
In overweight adults aged 40–65 who do not smoke, the level of nitrite in saliva is linked to the level of nitrate in saliva and blood, but not to nitrite in blood, showing that salivary nitrite comes from dietary nitrate processed by bacteria in the mouth, not from nitric oxide produced elsewhere in the body.
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.
In overweight adults aged 40–65 who do not smoke, saliva test strips from Berkeley and Neogenesis do not match the levels of nitrite and nitrate in the blood, so they cannot measure endothelial nitric oxide synthase activity or systemic nitric oxide levels.
The amount of nitrite in saliva cannot be used to determine how much nitric oxide is available in the bloodstream or the level of nitrite circulating in the blood.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.