Clinical trial NCT03995602: The Effects of Dragon Fruit Consumption on Vascular Function.
Official title: A Randomised, Placebo-controlled, Crossover Study of the Effects of Dragon Fruit Effects of Dragon Fruit (Pitaya) Consumption on Vascular Function in Healthy Males and Females
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Healthy Men and Women
Keywords: vascular function
endothelial function
betalains
dragon fruit
pitaya
Lead sponsor: King's College London
Sponsor class: OTHER
First posted: 2019-06-24
Enrollment: 20
Sex: ALL
Minimum age (years): 18
Maximum age (years): 40
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: BASIC_SCIENCE

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.


Eligibility criteria: 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.

Primary outcomes:
measure: Changes in flow mediated dilation (FMD) of the brachial artery
timeFrame: Baseline & 2 weeks
Secondary outcomes:
measure: Changes in flow mediated dilation (FMD) of the brachial artery
timeFrame: Baseline & 2, 3 and 4 hour post-consumption
measure: Changes in blood pressure
timeFrame: Baseline & 2, 3 and 4 hour post-consumption
measure: Changes in blood pressure
timeFrame: Baseline & 2 weeks
measure: Changes in heart rate
timeFrame: Baseline & 2, 3 and 4 hour and 2 weeks post-consumption
measure: Changes blood flow velocity
timeFrame: Baseline & 2, 3 and 4 hour and 2 weeks post-consumption
measure: Changes in pulse wave velocity (PWV)
timeFrame: Baseline & 3 hour and 2 weeks post-consumption.
measure: Changes augmentation Index (AIx)
timeFrame: Baseline & 3 hour and 2 weeks post-consumption.
measure: Number of volunteers with treatment-related adverse events
timeFrame: Baseline & 12 weeks
Other outcomes:
measure: Plasma and urine betalains and (poly)phenol metabolites
timeFrame: Baseline and 3 hours and 2 weeks post consumption
Locations:
city: London
country: United Kingdom
facility: King's College London
state: England
Study officials:
affiliation: King's College London
name: Ana Rodriguez-Mateos, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Cheok A, Xu Y, Zhang Z, Caton PW, Rodriguez-Mateos A. Betalain-rich dragon fruit (pitaya) consumption improves vascular function in men and women: a double-blind, randomized controlled crossover trial. Am J Clin Nutr. 2022 May 1;115(5):1418-1431. doi: 10.1093/ajcn/nqab410.