Impact of Oranges on Cardiovascular Health

Blood Pressure Clinical Trial

Official title:

Bioavailability of Flavanones Compounds and Their Impact on Cardiovascular Health

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01935362
• Other study ID #: MEEC 12-025
• Status: Completed
• Phase: Phase 1/Phase 2
• First received: August 20, 2013
• Last updated: March 31, 2014
• Start date: June 2013
• Est. completion date: March 2014

Study information

• Verified date: March 2014
• Source: University of Leeds
• Contact: n/a
• Is FDA regulated: No
• Health authority: United Kingdom: Research Ethics Committee
• Study type: Interventional

Clinical Trial Summary

Cardiovascular disease (CVD) is the leading cause of deaths in the Western world. Established risk factors include high LDL cholesterol, high blood pressure and diabetes. Poor blood vessel health is considered a predictor of future CVD risk, but can be reversed. Several different measurements can be used to determine blood vessel health; such as blood pressure (BP), and newer techniques which measure blood flow through the arteries after a blood pressure cuff restricts blood flow for a few minutes in one arm.

Flavonoids are compounds found in plant-based foods, and are associated with a reduced risk of CVD. From the previous studies, there is strong evidence that orange juice and citrus foods which have higher amount of specific citrus flavonoids improved cardiovascular risk factors such as BP and blood vessel health. Absorption of citrus flavonoids occurs in the colon after bacteria breakdown the forms found in food. After the flavonoids are absorbed into the blood they are modification by liver enzymes before they are excreted in the urine. A large range of citrus flavonoid have been found excreted in the urinary, ranging anywhere from 0-57% of the dose. Variation in the potential health effect may reflect the level of the citrus flavonoid absorbed, and this is not often considered in human studies.

This study is a 4-week double-blinded, randomized, cross-over intervention trial using a commercially-available orange juice supplement and a placebo control. The aims of the study are to determine whether orange juice supplements reduce blood pressure and improve blood vessel health after 4 weeks. Furthermore, to determine if there is a relationship between absorption of flavonoids (as measured by urinary excretion) and changes in blood pressure or blood vessel health.

The participants will need to attend 4 sessions on 4 separate study days, every 4 weeks for 12 weeks. On each study day they will have their weight, height, waist circumference, and blood pressure measured. A finger-prick blood sample, using a single-use lancet (Accu-Chek Safe T Pro Plus), will be taken to check the fasting blood glucose level. Blood flow in fingertips will be monitored before and after reducing blood flow in your forearm using a blood pressure cuff (called an EndoPAT). Participants will be asked to collect urine for 24 hr on each of the study days, and to consume the supplements provided daily for two sets of 4 weeks (there will be 4 weeks in the middle without any supplements).

An improvement in blood pressure and/or blood flow will provide evidence that blood vessel health has improved through short-term (4 week) use of a citrus flavonoid supplement

Recruitment information / eligibility

• Status: Completed
• Enrollment: 25
• Est. completion date: March 2014
• Est. primary completion date: February 2014
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 30 Years to 60 Years

Eligibility

Inclusion Criteria:

• No known cardiovascular disease or diabetes

• Age between 30-60 years

• Heavier than average (Body mass index, BMI = 25 kg/m2)

• Currently non smoker

• Willing to consume orange juice supplements for 2 months

• Male and female are equally eligible as not mentioned on advert

Exclusion Criteria:

• Those who Taken any antibiotics in the 2 months prior to the study

• Those who consume dietary or herbal supplements

• previous surgery on gastrointestinal tract

• Those who currently taking medication

• Current smokers, or ex-smokers ceasing < 3 months ago

• pregnant or breast feeding

• Those with known allergies to the intervention treatment

Study Design

Allocation: Randomized, Endpoint Classification: Bio-availability Study, Intervention Model: Crossover Assignment, Masking: Double Blind (Investigator, Outcomes Assessor), Primary Purpose: Prevention

Related Conditions & MeSH terms

• Blood Pressure
• Cardiovascular Disease Risk Reduction
• Cardiovascular Diseases
• Endothelial Dysfunction

Intervention

Dietary Supplement:
• Citrus supplement

• Placebo

Locations

Country	Name	City	State
United Kingdom	School Of Food Science and Nutrition, University Of Leeds	Leeds	West Yorkshire

Sponsors (2)

Lead Sponsor	Collaborator
University of Leeds	Dr Andrea Day and Prof Gary Williamson

Country where clinical trial is conducted

United Kingdom, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	blood pressure	Change in systolic and diastolic blood pressure	Baseline and 4 weeks	No
Primary	An improvement in blood flow	Change in blood flow using Endo-PAT device	Baseline and 4 weeks	No
Secondary	blood glucose	Change in blood glucose level in plasma,	Baseline and 4 weeks	No
Secondary	bioavailability of flavanones compounds	Change of urine flavanones from the baseline and after 4 weeks of each arm	Baseline and 4 weeks	No

External Links

•   Click here for more information about this study: Impact of oranges on cardiovascular health