Evaluating the Impact of Various Dietary Nitrate Supplements on Oral Health

NCT06956612 | Recruiting

• 1 other identifier: 2966/53998
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

This study aims to investigate the effects of different dietary nitrate supplements, versus placebo, on microbiological and immunological markers associated with oral health in people aged 18-65 years. The main research questions are:

• How do different dietary nitrate supplements (beetroot crystals vs. beetroot juice) affect oral health markers, including salivary pH and oral microbiome composition?
• What is the acceptability and ease of integrating one of dietary nitrate supplements, made from beetroot but processed as freeze dried crystals or juice, into the daily diet? To answer these questions, the study will compare results from three groups of participants, who will be randomly assigned to one of the following study arms: Group 1: The control group will consume a placebo beetroot supplement completely free of nitrate in juice form. Group 2: The beetroot juice group will consume a beetroot supplement standardised to contain \~ 400 mg of nitrate in juice form. Group 3: The beetroot crystals group will consume a beetroot supplement standardised to contain \~400 mg of nitrate in freeze dried crystal form. The study will follow a randomised, single-blind, placebo-controlled, parallel design, and the intervention will last for four weeks. Data will be collected by providing pre- and post-intervention saliva samples tongue swabs, and various questionnaires will be completed at baseline and at the end of the study. In addition, at the end of the second week of the intervention period, participants will be asked to collect a saliva sample over three consecutive days at home.

Conditions

Oral Health; Dietary Nitrate

Keywords

Dietary nitrate; oral health; salivary acidity; oral microbiome

Outcome Measures

Primary Outcomes (2)

• Saliva pH

  Prior to and following the intervention, participants will provide an unstimulated saliva sample for pH measurement. The pH of each saliva sample will be measured using a pre-calibrated pH meter (±0.01 pH accuracy). Measurements will be performed in three independent replicates for each sample, with the three values recorded and then averaged. This average is used for the final pH value of the sample, helping to reduce the influence of random errors and improve the accuracy and reliability of the results. The device is recalibrated prior to measurements using standard calibration solutions to ensure accurate readings.

  4 weeks

• Oral microbiome

  Prior to and following the intervention, participants will provide unstimulated saliva and tongue swab samples. DNA will be extracted from both the saliva and tongue swab samples, and 16S rRNA sequencing will be performed to identify and quantify changes in the oral microbiome.

  4 weeks

Secondary Outcomes (8)

• Salivary nitrate/ nitrite concentrations

  4 weeks

• Saliva flow rate

  4 weeks

• Salivary biomarkers

  4 weeks

• Dry mouth severity (Xerostomia)

  4 weeks

• Oral hygiene behaviours

  4 weeks

Study Arms (3)

Control

PLACEBO COMPARATOR

Daily supplementation with 70 ml nitrate-depleted Beet It Sport Shots, James White Ltd (\~0mg dietary nitrate)

Dietary Supplement: Control (Placebo comparator)

Juice

ACTIVE COMPARATOR

Daily supplementation with 70 ml Beet It Sport Shots, James White Ltd (\~400mg nitrate).

Dietary Supplement: Juice (Active comparator)

Crystals

EXPERIMENTAL

Daily supplementation with 20g Beet It Sport Crystals, James White Ltd (\~400mg nitrate).

Dietary Supplement: Crystals (Experimental)

Interventions

Control (Placebo comparator) DIETARY_SUPPLEMENT

The control group will consume a placebo supplement, entirely free of nitrate, in the form of juice (70 ml) for four weeks while maintaining their habitual diet.

Control

Juice (Active comparator) DIETARY_SUPPLEMENT

The juice group will consume a beetroot supplement enriched with \~400 mg of nitrate in juice form (70 ml) for four weeks while maintaining their habitual diet.

Juice

Crystals (Experimental) DIETARY_SUPPLEMENT

The crystals group will consume a beetroot supplement enriched with \~400 mg of nitrate in crystals form (20g) for four weeks while maintaining their habitual diet.

Crystals

Eligibility Criteria

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

You may qualify if:

• Healthy volunteers
• Aged 18 - 65 years.

You may not qualify if:

• Aged less than 18 or more than 65 years old.
• Current smoking
• Alcohol consumption of greater than14 units per week.
• Diagnosis of a chronic disease (e.g., cardiovascular disease, diabetes, cancer, or gastrointestinal disorders), including oral diseases.
• Use of antibiotics within the past three months or medications/nutritional supplements that may affect the oral cavity (e.g., prebiotics, probiotics, or hormone replacement therapy).
• Regular use of antibacterial mouthwash or xylitol-containing products (e.g., gum or toothpaste) or the use of proton pump inhibitors.
• Presence of braces/invisalign or dentures.
• Known allergy to any food, including beets
• Adherence to dietary restrictions (e.g., weight loss diet)
• Eating disorders that may limit participation in the study.
• Currently pregnant, breastfeeding or trying to become pregnant.
• Participation in other studies.

Sponsors & Collaborators

• Shatha Alhulaefi: lead
• Northumbria University: collaborator
• Edith Cowan University: collaborator
• University of the West of Scotland: collaborator

Study Sites (1)

Newcastle University, Newcastle upon Tyne, Tyne and Wear NE2 4HH

Newcastle, NE2 4HH, United Kingdom

RECRUITING

Study Officials

• Oliver Shannon, PhD

  Newcastle University

  PRINCIPAL INVESTIGATOR

• Anthony Watson, PhD

  Newcastle University

  PRINCIPAL INVESTIGATOR

• Sheena Ramsay, PhD

  Newcastle University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Shatha Alhulaefi

CONTACT

+44783361076; S.Alhulaefi2@newcastle.ac.uk

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Masking Details: This study will use a single-blind design, where the participants will not know whether they receive the real supplement or the placebo. Participants will be told they might receive either crystals or juice, but they won't know whether it's an active supplement or a placebo.
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Doctoral Researcher

Study Record Dates

• First Submitted: April 24, 2025
• First Posted: May 4, 2025
• Study Start: May 23, 2025
• Primary Completion: December 1, 2025
• Study Completion: April 1, 2026
• Last Updated: May 28, 2025

Record last verified: 2025-05

Locations

GB (1)