Impact of Consumption of Cowpea Leaves on Postprandial Blood Glucose in Black Adults, a Pilot Study

Not Applicable

Completed

• Conditions: Black Ethnicity
• Interventions: Other: Jam mixed with green food colour; Other: Cowpea leaves mixed with Jam

• Registration Number: NCT05750316
• Lead Sponsor: University of Reading

Brief Summary

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. People of black ethnicity have higher risk of diabetes. Vegetables may help in the regulation of blood glucose. Cowpea, also referred to as black-eyed peas (Vigna unguiculata) 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.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2023-02-19
• Study First Submitted QC: 2023-02-19
• Study Start: 2023-03-01
• Study First Posted: 2023-03-01
• Primary Completion: 2023-07-13
• Study Completion: 2023-07-13
• Status Verified: 2024-07
• Last Update Submitted: 2024-07-16
• Last Update Posted: 2024-07-18

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 12

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 & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Jam with green food colour	Jam mixed with green food colour	Apricot jam mixed with green colouring and spread on bread
Freeze dried cowpea leaves mixed in jam	Cowpea leaves mixed with Jam	6g of freeze-dried cowpea leaves (equivalent to one portion of vegetables) mixed with apricot jam and spread on bread.

Primary Outcome Measures

Name	Time	Method
Change in postprandial blood glucose measured by incremental area under the curve and area under the curve	At baseline (t=0 hours) and 15 minutes interval until (t=3 hours)	Postprandial blood glucose measured by a continuous glucose monitor. The incremental area under curve and area under the curve will be used as a measure of the postprandial blood glucose

Secondary Outcome Measures

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

Trial Locations

Locations (1)

University of Reading; 🇬🇧 Reading, United Kingdom