The Effect of Dietary Nitrate on the Oral Microbiome

Sponsor
University of Exeter (Other)
Overall Status
Completed
CT.gov ID
NCT03467061
Collaborator
(none)
101
1
3
39.8
2.5

Study Details

Study Description

Brief Summary

This study evaluates whether dietary manipulation of the oral microbiota modulates cardiovascular health through effects on nitric oxide bioavailability.

Condition or Disease Intervention/Treatment Phase
  • Dietary Supplement: Nitrate-rich beetroot juice
  • Dietary Supplement: Nitrate-depleted beetroot juice
  • Other: Mouthwash
N/A

Detailed Description

Nitric oxide is an important molecule for human health because it controls blood flow and blood pressure. With aging, our ability to make nitric oxide gets worse and our blood pressure tends to increase. We can help the body produce more nitric oxide by supplementing the diet with vegetables, such as beetroot juice, which contains high amounts of nitrate. This has been shown to improve blood flow and blood pressure. The bacteria inside our mouths play an important role in helping convert the ingested nitrate to nitric oxide. The reason for this study is to find out whether there are differences in oral bacteria between young and older adults, and how the oral bacterial community and blood flow and blood pressure might change when diet is supplemented with natural, nitrate-rich beetroot juice and when we use antibacterial mouthwash. This study will help us understand how the bacteria inside our mouths might be useful for keeping us healthy.

Study Design

Study Type:
Interventional
Actual Enrollment :
101 participants
Allocation:
Randomized
Intervention Model:
Crossover Assignment
Masking:
Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose:
Basic Science
Official Title:
The Effect of Dietary Nitrate on the Oral Microbiota, Markers of Nitric Oxide Bioavailability and Cardiovascular Health in in Young and Older Adults
Actual Study Start Date :
Jan 10, 2018
Actual Primary Completion Date :
May 6, 2021
Actual Study Completion Date :
May 6, 2021

Arms and Interventions

Arm Intervention/Treatment
Active Comparator: Nitrate-rich beetroot juice

2 x 70mL concentrated juice per day for 14 days

Dietary Supplement: Nitrate-rich beetroot juice
concentrated beetroot juice

Placebo Comparator: Nitrate-depleted beetroot juice

2 x 70mL concentrated juice per day for 14 days

Dietary Supplement: Nitrate-depleted beetroot juice
concentrated beetroot juice

Other: Antibacterial mouthwash

2 x 10mL antibacterial mouthwash per day for 14 days

Other: Mouthwash
2 x 10 mL antibacterial mouthwash per day for 14 days

Outcome Measures

Primary Outcome Measures

  1. Quantity of nitrate -reducing bacteria [14 days]

    Change in total quantity of nitrate-reducing bacteria as measured by sequencing bacterial 16S rRNA genes

Secondary Outcome Measures

  1. Nitric oxide bioavailability - plasma nitrite [14 days]

    Change in nitrite concentration of plasma as measured by ozone-based chemiluminescence

  2. Nitric oxide bioavailability - salivary nitrite [14 days]

    Change in nitrite concentration of saliva as measured by ozone-based chemiluminescence

  3. Nitric oxide bioavailability - plasma nitrate [14 days]

    Change in nitrate concentration of plasma as measured by ozone-based chemiluminescence

  4. Nitric oxide bioavailability - salivary nitrate [14 days]

    Change in nitrate concentration of saliva as measured by ozone-based chemiluminescence

  5. Blood pressure [14 days]

    Change in systolic and diastolic BP

  6. Flow mediated dilation [14 days]

    Change in flow mediated dilation

Eligibility Criteria

Criteria

Ages Eligible for Study:
18 Years to 80 Years
Sexes Eligible for Study:
All
Accepts Healthy Volunteers:
Yes
Inclusion Criteria:
  • Healthy young (18-30 yr) and older adults (65-80 yr)

  • Male and female

  • Willing to undergo the experiments as detailed in the informed consent documentation

  • Willing and capable of providing written, informed consent.

Exclusion Criteria:
  • Individuals receiving medication for pulmonary, cardiovascular, or metabolic conditions, ulcerative colitis or renal disease

  • Having an active oral disease or dentures

  • Having resting BP >140/90 mmHg

  • Having used antibiotics within 3 months

  • Lacking willingness or capacity to give informed consent.

Contacts and Locations

Locations

Site City State Country Postal Code
1 Diabetes & Vascular Medicine Research Centre, Clinical Research Facility Exeter Devon United Kingdom

Sponsors and Collaborators

  • University of Exeter

Investigators

  • Principal Investigator: Andrew M Jones, PhD, University of Exeter

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.
Responsible Party:
University of Exeter
ClinicalTrials.gov Identifier:
NCT03467061
Other Study ID Numbers:
  • 1718/14
First Posted:
Mar 15, 2018
Last Update Posted:
May 27, 2021
Last Verified:
May 1, 2021
Studies a U.S. FDA-regulated Drug Product:
No
Studies a U.S. FDA-regulated Device Product:
No

Study Results

No Results Posted as of May 27, 2021