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.

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.