The Effects of Nitrate-Rich Mouthwash on Vascular Tone

NCT07602764 | Not Yet Recruiting

• 1 other identifier: 2025-02639-01
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

High blood pressure (hypertension) is a major risk factor for cardiovascular disease. One important contributing factor to high blood pressure is reduced availability of nitric oxide (NO). Therefore, NO is an important molecule in maintaining healthy blood vessel function. Dietary nitrate, found in leafy greens, can serve as an alternative source of nitric oxide in the body. After ingestion, nitrate is converted to nitrite by bacteria residing in the oral cavity. Nitrite can subsequently be converted to NO when swallowed. Therefore, this nitrate-nitrite-nitric oxide pathway is dependent on oral bacteria. This study aims to assess whether rinsing the mouth with a nitrate-rich mouth rinse influences blood pressure in healthy adults. Also, concentrations of nitrate and nitrite in plasma and saliva will be measured following the nitrate-mouth rinse exposure.

Conditions

Blood Pressure Regulation

Keywords

Nitrate reduction; Nitrate supplement; Blood pressure regulation; Plasma nitrate; Plasma nitrite; Saliva nitrate; Saliva nitrite; Mouth rinse

Outcome Measures

Primary Outcomes (2)

• Blood pressure before and at regular intervals within the 24 hours after nitrate exposure.

  Blood pressure will be measured before and with regular intervals after nitrate exposure. The measurements will be registered as systolic and diastolic measurements from clinic blood pressure and home blood pressure.

  Baseline (prior to nitrate exposure) and during the 24 hours after nitrate exposure.

• Oral nitrite production before and at regular intervals within the 24 hours after nitrate exposure.

  The nitrite production is measured using the rapid Griess assay (RGA) - a chairside semi-quantitative nitrite concentration estimation tool for use in several different oral samples. The RGA provides nitrite estimation on a grading scale of 0-5 with nitrite concentrations intervals.

  Baseline (prior to nitrate exposure) and during the 24 hours after nitrate exposure

Secondary Outcomes (8)

• Plasma and salivary nitrate and nitrite levels before and after nitrate exposure.

  Baseline (prior to nitrate exposure) and 1 hour after nitrate exposure.

• Salivary pH levels at regular intervals.

  Baseline (prior to nitrate exposure) and during the 24 hours after nitrate exposure.

• Orthostatic blood pressure before and at regular intervals within the 24 hours after nitrate exposure.

  Baseline (prior to nitrate exposure) and during the 24 hours after nitrate exposure.

• Salivary secretion rate before and after nitrate exposure.

  Baseline (prior to nitrate exposure) and during the 24 hours after nitrate exposure.

• Relative abundance in cultivable oral microbial composition after nitrate exposure

  Baseline (prior to nitrate exposure) and during the 24 hours after nitrate exposure.

Study Arms (4)

Test mouth rinse

EXPERIMENTAL

In this arm participants will receive nitrate rich-mouth rinse

Dietary Supplement: Nitrate-rich mouth rinse

Placebo mouth rinse

PLACEBO COMPARATOR

In this arm participants will receive placebo mouth rinse

Dietary Supplement: Placebo

Test drink

ACTIVE COMPARATOR

In this arm participants will receive nitrate-rich drink

Dietary Supplement: Nitrate-rich drink

Placebo drink

PLACEBO COMPARATOR

In this arm participants will receive placebo drink

Dietary Supplement: Placebo

Interventions

Nitrate-rich mouth rinse DIETARY_SUPPLEMENT

The oral cavity is rinsed with nitrate from mouth rinse, rather than ingested.

Also known as: Nitrate mouth rinse

Test mouth rinse

Nitrate-rich drink DIETARY_SUPPLEMENT

Nitrate is ingested, rather than rinsed and spit out

Also known as: Nitrate drink

Test drink

Placebo DIETARY_SUPPLEMENT

This mouth rinse is devoid of nitrates

Placebo mouth rinse

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• ≥18 years of age; and
• clinic blood pressure \<140/\<90 mmHg.

You may not qualify if:

• hypertension;
• systemic medication (other than the oral contraceptive pill);
• antibiotic treatment within the last 3 months;
• active smoking status and BMI \> 30;
• prior gastric by-pass surgery;
• self-reported use of antiseptic mouthwash or toothpaste;
• self-reported use of tongue scrapes; and
• active periodontal disease or caries that needs treatment.

Sponsors & Collaborators

• Göteborg University: lead

Study Sites (1)

Odontologen, University of Gothenburg

Gothenburg, Västra Götaland County, 41390, Sweden

Location

Study Officials

• Amina Basic, PhD, DDS

  Göteborg University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Simeon KB Mavropoulos, DDS, MSc

CONTACT

+46766185930; simeon.mavropoulos@gu.se

Amina Basic, PhD, DDS

CONTACT

+46766185930; amina.basic@gu.se

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: PhD, DDS

Study Record Dates

• First Submitted: December 29, 2025
• First Posted: May 22, 2026
• Study Start: April 1, 2026
• Primary Completion (Estimated): December 1, 2028
• Study Completion (Estimated): December 1, 2028
• Last Updated: May 22, 2026

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will not share

Locations

SE (1)