Impact of Consumption of Cowpea Leaves on Blood Glucose

Intake of foods high in carbohydrates causes a spike in glucose in the blood. Repeated high blood glucose spikes are associated with an increased risk of diabetes. Polyphenols, which are abundant in vegetables, may influence how the body utilises carbohydrates. Cowpea, also referred to as black-eyed peas (Vigna unguiculata (L.) Walp.) leaves, contain polyphenols and fibre that can help regulate blood glucose.

The study will be an acute, single-blind, randomised control trial with a cross-over design involving healthy black participants aged ≥18 years. This clinical trial aims to investigate if consuming cowpea leaves can reduce blood glucose spikes after consuming a meal high in carbohydrates. Participants will be randomised to consume either bread with jam containing freeze-dried cowpea leaves (active intervention) or jam without any freeze-dried powder (control group). Blood glucose will be monitored before the intervention and every 15 minutes after the intervention using a continuous glucose monitor.

Study Overview

• Status: Recruiting
• Conditions: Blood Glucose
• Intervention / Treatment: Other: Cowpea leaves mixed with Jam; Other: Jam mixed with green food colour

• Study Type: Interventional
• Enrollment (Anticipated): 26
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Charlotte E Mills, PhD; Phone Number: 7108 01183787108; Email: c.e.mills@reading.ac.uk

Study Locations

• United Kingdom
  • Reading, United Kingdom, RG6 6AH
    • Recruiting
    • University of Reading
    • Contact: Charlotte E Mills, PhD; Phone Number: 7108 011837871008; Email: c.e.mills@reading.ac.uk

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Adults aged ≥ 18 years
• Participants from Black, Black British, Caribbean or African ethnic backgrounds,which includes: Caribbean, African, Any other Black, Black British, or Caribbean background
• Should be able to give informed consent
• Should be willing to provide GP's contact details

Exclusion Criteria:

• Pregnant or lactating mothers
• Special dietary requirements such as vegetarians and vegans
• Participants who are on a specialised diet such as a weight reduction diet
• Having any chronic illness or taking medication for chronic illness
• Participants whose blood results indicate illness
• Participants on mediation for hypertension or hyperlipidaemia
• Sportsmen or women or vigorous exercise for more than 5 times per week
• Alcohol (more than 14 units per week) or drug abusers.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Freeze dried cowpea leaves mixed in jam; 6g of freeze-dried cowpea leaves (equivalent to one portion of vegetables) mixed with apricot jam and spread on bread.	Other: Cowpea leaves mixed with Jam; 6g of freeze-dried cowpea leaves, equivalent to 80g(a portion) of vegetables mixed with Jam and spread on bread
Active Comparator: Jam with green food colour; Apricot jam mixed with green colouring and spread on bread	Other: Jam mixed with green food colour; Jam with green food colouring spread on bread

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in blood glucose	Blood glucose measured by continous glucose monitor	At baseline (t=0 hours) and 15 minutes interval until (t=3 hours)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in blood pressure	Systolic and diastolic blood pressure by blood pressure monitor	At baseline (t=0 hours) and every 30 minute until (t=3 hours)
Microvascular blood flow	Microvascular blood flow using Laser doppler Imaging with Iontophoresis	At baseline (t=0 hours) and (t=2.5 hours)

Collaborators and Investigators

• Sponsor: University of Reading

Study record dates

Study Major Dates

• Study Start (Actual): March 1, 2023
• Primary Completion (Anticipated): July 30, 2023
• Study Completion (Anticipated): July 30, 2023

Study Registration Dates

• First Submitted: February 19, 2023
• First Submitted That Met QC Criteria: February 19, 2023
• First Posted (Actual): March 1, 2023

Study Record Updates

• Last Update Posted (Actual): May 10, 2023
• Last Update Submitted That Met QC Criteria: May 8, 2023
• Last Verified: May 1, 2023

More Information

Terms related to this study

• Keywords: Blood Pressure; Blood Glucose; Polyphenols; Vegetable; Cowpea
• Other Study ID Numbers: 06/2023

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No