Adding nitrate to everyday oat-based foods to boost nitric oxide and support blood vessel health.

An Open-Label, Randomised, Crossover Study to Investigate the Feasibility of Nitrate Fortification in Commonly Consumed Foods for Regulating Nitric Oxide Metabolism in Healthy Individuals

We will test whether adding inorganic nitrate to oat-based foods boosts nitric oxide levels and lowers blood pressure in healthy adults aged 18–60.

Quick facts

• Phase: NA
• Study type: Interventional
• Enrollment: 30 (estimated)
• Ages: 18 Years to 60 Years
• Sex: All
• Sponsor: Queen Mary University of London (other)
• Locations: 1 site (London)
• Trial ID: NCT07172425 on ClinicalTrials.gov

What this trial studies

This open-label, randomized crossover study will recruit 30 healthy adults (15 men, 15 women) to receive three different potassium nitrate–fortified oat-based foods (biscuits, porridge, cereal bar) across separate visits. Participants will attend seven clinic visits for serial blood pressure measurements and collection of blood, urine, and saliva samples up to 24 hours after each supplement to measure nitrate, nitrite, and vascular responses. Each participant acts as their own control by receiving all three fortified products in random order. The primary focus is short-term changes in nitric oxide bioavailability and clinic blood pressure following single consumption of each fortified food.

Who should consider this trial

Good fit: Ideal participants are healthy adults aged 18–60 who can give informed consent, are not pregnant, are not taking chronic medications, and have no history of hypertension, diabetes, or major cardiovascular disease.

Not a fit: People with existing hypertension, diabetes, other chronic illnesses, pregnancy, or those taking chronic medications are unlikely to benefit from this healthy-volunteer test and are excluded.

Why it matters

Potential benefit: If successful, this approach could provide a low-cost, widely acceptable way to increase nitric oxide intake and help reduce population blood-pressure risk.

How similar studies have performed: Previous work using beetroot juice or potassium nitrate capsules has shown short-term blood-pressure lowering and improved endothelial function, though food fortification is a newer, less-studied delivery approach.

Eligibility criteria

Inclusion Criteria:

1. Healthy volunteer.
2. Aged ≥18 years and ≤ 60 years.
3. Willing to provide informed consent.
4. Able to understand and comply with protocol requirements, instructions, and stated restrictions.

Exclusion Criteria:

A volunteer will not be eligible for inclusion in this study if any of the following criteria are met:

1. Unwilling to provide consent.
2. People with chronic health conditions requiring medication.
3. Pregnant females, or those with a possibility of being pregnant.
4. History of hypertension and /or diabetes.
5. History of any serious illnesses, including recent infections or trauma.
6. History of symptomatic coronary artery disease, stroke, or other known atherosclerotic diseases.
7. People who will commence or who are likely to commence treatment with non-steroidal anti-inflammatory drugs (NSAIDs) other than aspirin, from screening until study completion.
8. Self-declared alcohol or drug abuse within the past 6 months.
9. Three-month prior history of regular alcohol consumption exceeding an average weekly intake of \> 28 units (or an average daily intake of greater than 3 units) for males, or an average weekly intake of \> 21 units (or an average daily intake of greater than 2 units) for females. One unit is equivalent to a half pint (284mL) of beer/lager; 25mL of spirits, or 125mL of wine.
10. Taking systemic medication (other than the oral contraceptive pill).
11. Recent (within 2 weeks) self-reported use of mouthwash or tongue scrapers.
12. Recent (within 2 weeks) or current antibiotic use.
13. Recent (within 1 week) use of NO3- or NO2- supplements.
14. History, or recent treatment of (within the last 3 months) for any oral condition (excluding caries), including gingivitis, periodontitis and halitosis.
15. History of, or recent treatment for, any blood-borne infectious disease such Hepatitis B or C virus, or HIV.
16. Current smokers (including vaping) or have smoked within the last 6 months.
17. Diagnosis of rheumatoid arthritis, connective tissue disorders, and other conditions known to be associated with chronic inflammation (e.g., Inflammatory Bowel Disease).
18. People who have donated more than 500mL of blood within 56 days prior to the study commencement.
19. Known allergy to celery, gluten, crustaceans, eggs, lupin, milk, mustard, peanuts, sesame, soybeans, tree nuts, oats, palm oil, sugar, cranberries, sunflower oil, invert syrup, sodium bicarbonate.

Where this trial is running

London

• The William Harvey Research Institute, Centre for Cardiovascular Medicines and Devices, Queen Mary University of London — London, United Kingdom (RECRUITING)

Study contacts

• Study coordinator: Amrita Ahluwalia, BSc PhD

Conditions: Healthy Volunteers, Nitric Oxide, Vascular Function, Blood pressure, Oral microbiome profiling, Nitric oxide bioavailability, Inorganic nitrate fortification