Antibacterial mouthwash blunts oral nitrate reduction and increases blood pressure in treated hypertensive men and women.
Level 2 - randomized trial
Individual randomized controlled crossover trial
PubMed 25359409 · doi:10.1093/ajh/hpu192
What was done
Fifteen treated hypertensive men and women (mean age 65 years) participated in a randomized controlled crossover trial comparing 3 days of antibacterial mouthwash use to a control condition (water). The authors measured oral nitrate-to-nitrite reduction, salivary and plasma nitrate and nitrite, plasma cyclic guanosine monophosphate (cGMP), and systolic and diastolic blood pressure.
What was found
Compared to water control, 3 days of antibacterial mouthwash significantly decreased oral nitrate-to-nitrite reduction (P = 0.02), decreased salivary nitrite (P = 0.01), and increased salivary nitrate (P < 0.001), with a non-significant trend toward decreased plasma nitrite (P = 0.09). Mouthwash use caused a statistically significant increase in systolic blood pressure of 2.3 mm Hg (95% CI: 0.5 to 4.0; P = 0.01), but had no significant effect on diastolic blood pressure (P = 0.4) or plasma cGMP (P = 0.7).
Why it matters
This trial demonstrates that oral microbiome-mediated nitrate reduction contributes to blood pressure regulation in treated hypertensive patients, suggesting antiseptic mouthwash can disrupt systemic nitric oxide bioavailability.
Limits
The trial had a very small sample size (n = 15) and a very short intervention window (3 days), preventing assessment of chronic effects or clinical cardiovascular outcomes. The abstract does not specify the active antibacterial agent used or control for variations in dietary nitrate intake.
Cited by
- supports Oral bacteria produce nitric oxide precursors, and mouthwash kills the oral microbes responsible for nitric oxide production.