The Effects of Dragon Fruit Consumption on Vascular Function.

NCT03995602 | Completed

• 1 other identifier: DRAGON Study
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

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.

Conditions

Healthy Men and Women

Keywords

vascular function; endothelial function; betalains; dragon fruit; pitaya

Outcome Measures

Primary Outcomes (1)

• Changes in flow mediated dilation (FMD) of the brachial artery

  Determine changes in flow mediated dilation (FMD) of the brachial artery after 2 weeks consumption of 24 g freeze-dried dragon fruit.

  Baseline & 2 weeks

Secondary Outcomes (8)

• Changes in flow mediated dilation (FMD) of the brachial artery

  Baseline & 2, 3 and 4 hour post-consumption

• Changes in blood pressure

  Baseline & 2, 3 and 4 hour post-consumption

• Changes in blood pressure

  Baseline & 2 weeks

• Changes in heart rate

  Baseline & 2, 3 and 4 hour and 2 weeks post-consumption

• Changes blood flow velocity

  Baseline & 2, 3 and 4 hour and 2 weeks post-consumption

Other Outcomes (1)

• Plasma and urine betalains and (poly)phenol metabolites

  Baseline and 3 hours and 2 weeks post consumption

Study Arms (2)

Dragon fruit first then placebo

EXPERIMENTAL

2 weeks of dragon fruit juice intake or placebo with crossover to the other

Dietary Supplement: Dragon fruit juice drink; Dietary Supplement: Placebo

Placebo first then dragon fruit

EXPERIMENTAL

2 weeks of dragon fruit juice intake or placebo with crossover to the other

Dietary Supplement: Dragon fruit juice drink; Dietary Supplement: Placebo

Interventions

Dragon fruit juice drink DIETARY_SUPPLEMENT

Dragon fruit drink containing 24 g of freeze-dried dragon fruit powder dissolved in low nitrate water.

Dragon fruit first then placebo; Placebo first then dragon fruit

Placebo DIETARY_SUPPLEMENT

Drink with macro- and micro-nutrient matched against the intervention drink.

Dragon fruit first then placebo; Placebo first then dragon fruit

Eligibility Criteria

• Age: 18 Years - 40 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Healthy men and women aged 18-40 years old
• 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.
• Are able to understand the nature of the study.
• Able to give signed written informed consent.
• Signed informed consent form.

You may not qualify if:

• Medical history of cardiovascular disease including coronary artery disease, cerebrovascular disease and peripheral artery disease.
• Hypertensive, as defined as SBP superior or equal to 140 mmHg.
• Obese participants, defined as BMI superior or equal to 30.
• Medical history of diabetes mellitus, metabolic syndrome, terminal renal failure or malignancies.
• Abnormal heart rhythm (lower or higher than 60-100 bpm).
• Allergies to dragon fruit, cactus pear or other significant food allergy.
• Subjects under medication that can affect the cardiovascular system or on vitamin/dietary supplements.
• Subjects who have lost more than 10% of their weight in the past 6 months or are currently in a diet
• Subjects who reported participant in another study within one month before the study start.
• Subjects who smokes.
• Pregnant women or planning to become pregnant in the next 6 months.
• 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.

Sponsors & Collaborators

• King's College London: lead

Study Sites (1)

King's College London

London, England, SE1 9NH, United Kingdom

Location

Related Publications (1)

• 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.

  PMID: 35265960 DERIVED

Study Officials

• Ana Rodriguez-Mateos, PhD

  King's College London

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Lecturer in Nutritional Sciences

Study Record Dates

• First Submitted: June 20, 2019
• First Posted: June 24, 2019
• Study Start: June 18, 2019
• Primary Completion: January 22, 2020
• Study Completion: January 22, 2020
• Last Updated: June 7, 2021

Record last verified: 2021-06

Data Sharing

• IPD Sharing: Will not share

Locations

GB (1)