The Claim

Supplementation with Streptococcus salivarius M18 at a dose of 2.5 billion colony-forming units daily for 14 days increases plasma nitrite concentration from approximately 173 nM to 223 nM in healthy adult males, indicating a biologically meaningful enhancement in nitric oxide bioavailability, despite no change in salivary nitrite or oral microbiome composition.

Source: The Probiotic Streptococcus salivarius M18 Increases Plasma Nitrite but Does Not Alter Blood Pressure: A Pilot Randomised Controlled Trial

What the research says

Supports is higher

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

Supports
74score
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.

Cause and effect
1 study reviewed
In plain English

Taking Streptococcus salivarius M18 daily for 14 days raises plasma nitrite levels from 173 nM to 223 nM in healthy adult males, suggesting increased nitric oxide bioavailability, without altering salivary nitrite or the oral microbiome.

See the scientific wording

Supplementation with Streptococcus salivarius M18 for 14 days at a dose of 2.5 billion colony-forming units daily increases plasma nitrite concentration from approximately 173 nM to 223 nM in healthy adult males, indicating a biologically meaningful enhancement in nitric oxide bioavailability, despite no change in salivary nitrite or oral microbiome composition.

Why this might work

The probiotic bacteria change the way other bacteria in the mouth work, making them produce more nitrite from dietary nitrate. This extra nitrite gets absorbed into the blood, raising its levels without changing the number of bacteria or the nitrite in saliva.

Supported mechanismbased on 1 study

What the research says

1 study
  1. Study: The Probiotic Streptococcus salivarius M18 Increases Plasma Nitrite but Does Not Alter Blood Pressure: A Pilot Randomised Controlled Trial

    Taking this specific probiotic pill for two weeks raised a key chemical in the blood that helps blood vessels relax, even though it didn’t change the bacteria in the mouth or the nitrite in saliva.

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

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Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.