Healthy Men and Women
Conditions
Keywords
vascular function, endothelial function, betalains, dragon fruit, pitaya
Brief summary
Native to South America and South East Asia, the dragon fruit (pitaya) has become increasingly popular world-wide due to their vivid hue and bizarre structure. More importantly, their high levels of bioactive phytochemical betalains has sparked considerable scientific interest. Recent findings from in vitro and in vivo animal studies tentatively suggest that betalains may have ameliorative effects on vascular function. This will be a first randomised controlled trial aimed to explore the impact of dragon fruit consumption on blood pressure and other vascular parameters in healthy individuals. The study will feature a randomised, double-blinded, placebo-controlled and crossover design with flow-mediated dilatation (FMD) as primary outcome along with blood pressure and arterial stiffness as secondary outcomes. Cardiovascular biomarkers as well as relevant metabolites will also be determined from blood and urine samples collected from participants.
Interventions
DIETARY_SUPPLEMENTDragon fruit juice drink
Dragon fruit drink containing 24 g of freeze-dried dragon fruit powder dissolved in low nitrate water.
DIETARY_SUPPLEMENTPlacebo
Drink with macro- and micro-nutrient matched against the intervention drink.
Sponsors
King's College London
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 40 Years
Healthy volunteers
Yes
Inclusion criteria
1. Healthy men and women aged 18-40 years old 2. Subjects are willing to maintain their normal eating/drinking habits and exercise habits to avoid changes in body. weight over the duration of the study. 3. Are able to understand the nature of the study. 4. Able to give signed written informed consent. 5. Signed informed consent form.
Exclusion criteria
1. Medical history of cardiovascular disease including coronary artery disease, cerebrovascular disease and peripheral artery disease. 2. Hypertensive, as defined as SBP superior or equal to 140 mmHg. 3. Obese participants, defined as BMI superior or equal to 30. 4. Medical history of diabetes mellitus, metabolic syndrome, terminal renal failure or malignancies. 5. Abnormal heart rhythm (lower or higher than 60-100 bpm). 6. Allergies to dragon fruit, cactus pear or other significant food allergy. 7. Subjects under medication that can affect the cardiovascular system or on vitamin/dietary supplements. 8. Subjects who have lost more than 10% of their weight in the past 6 months or are currently in a diet 9. Subjects who reported participant in another study within one month before the study start. 10. Subjects who smokes. 11. Pregnant women or planning to become pregnant in the next 6 months. 12. Any reason or condition that in the judgment of the clinical investigator(s) may put the subject at unacceptable risk or that may preclude the subject from understanding or complying with the study's requirements.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Changes in flow mediated dilation (FMD) of the brachial artery | Baseline & 2 weeks | Determine changes in flow mediated dilation (FMD) of the brachial artery after 2 weeks consumption of 24 g freeze-dried dragon fruit. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Changes in flow mediated dilation (FMD) of the brachial artery | Baseline & 2, 3 and 4 hour post-consumption | Determine changes in flow mediated dilation (FMD) of the brachial artery at 2, 3, and 4 hour post consumption of 24 g freeze-dried dragon fruit. |
| Changes in blood pressure | Baseline & 2, 3 and 4 hour post-consumption | Determine changes in systolic and diastolic blood pressure at 2, 3, and 4 hour post consumption of 24 g freeze-dried dragon fruit. |
| Changes in heart rate | Baseline & 2, 3 and 4 hour and 2 weeks post-consumption | Determine changes in heart rate post consumption of 24 g freeze-dried dragon fruit. |
| Changes in pulse wave velocity (PWV) | Baseline & 3 hour and 2 weeks post-consumption. | Determine changes in pulse wave velocity post consumption of 24 g freeze-dried dragon fruit. |
| Changes augmentation Index (AIx) | Baseline & 3 hour and 2 weeks post-consumption. | Determine changes in augmentation index post consumption of 24 g freeze-dried dragon fruit. |
| Number of volunteers with treatment-related adverse events | Baseline & 12 weeks | The number of volunteers with treatment-related adverse events will be assessed by questionnaires and interviews. |
| Changes blood flow velocity | Baseline & 2, 3 and 4 hour and 2 weeks post-consumption | Determine changes in blood flow velocity post consumption of 24 g freeze-dried dragon fruit. |
Other
| Measure | Time frame | Description |
|---|---|---|
| Plasma and urine betalains and (poly)phenol metabolites | Baseline and 3 hours and 2 weeks post consumption | Measured by liquid chromotography- mass spectrometry (LC/MS) post consumption. |
Countries
United Kingdom
Outcome results
None listed