The Claim

Two weeks of antiseptic mouthwash (Listerine®) use does not significantly alter plasma nitrite concentrations or blood pressure in healthy young or older adults, despite reducing oral microbiome diversity in young adults, indicating that the mouthwash formulation does not broadly inhibit nitrate-reducing bacteria.

Source: Ageing modifies the oral microbiome, nitric oxide bioavailability and vascular responses to dietary nitrate supplementation.

What the research says

Supports is higher

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

Supports
76score
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.

Description
1 study reviewed
In plain English

Using Listerine® mouthwash for two weeks does not change blood nitrite levels or blood pressure in healthy young or older adults, even though it reduces the variety of bacteria in the mouth of young adults, showing that the mouthwash does not broadly affect bacteria that convert nitrate to nitrite.

See the scientific wording

Antiseptic mouthwash (Listerine®) for two weeks does not significantly alter plasma nitrite or blood pressure in healthy older or young adults, despite reducing oral microbiome diversity in the young, indicating that the mouthwash formulation used does not broadly inhibit nitrate-reducing bacteria.

Why this might work

Bacteria in the mouth convert dietary nitrate into nitrite, which enters the bloodstream and becomes nitric oxide to relax blood vessels and lower blood pressure. Antiseptic mouthwash kills some oral bacteria but does not remove the specific types that make nitrite, so nitrite levels and blood pressure stay unchanged.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: Ageing modifies the oral microbiome, nitric oxide bioavailability and vascular responses to dietary nitrate supplementation.

    Using Listerine for two weeks didn’t change nitrite levels or blood pressure in healthy people, even though it killed some mouth bacteria — meaning it didn’t mess with the good bacteria that help make nitric oxide.

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

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