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RAFA Study

Principal Investigator:

Dr Catherine Hughes

Name of the Study:

RAFA: Blood pressure lowering effect of B-vitamins in hypertensive adults with a genetic pre-disposition to elevated blood pressure.

Why is this Study important?

Hypertension is the world’s leading cause of preventable, premature death responsible for 7.6 million deaths worldwide. Blood pressure (BP) is usually treated with BP-lowering medication; however, despite the widespread availability and use of these drugs, BP control rates remain poor with only 50% of people reported to respond to current therapies. Genetic factors play a role in BP and a common genetic risk factor, prevalent in 12% of the NI population, called MTHFR, has been linked with hypertension.

Previous work at Ulster University has shown that supplementation with the B-vitamin riboflavin at the level you receive in your diet (1.6mg/day), can reduce BP in this individuals with this genetic risk factor by as much as 13 units. This reduction is clinically significant as reducing BP by a little as 2units reduces overall cardiovascular disease risk by 10%. MTHFR helps to generate another B-vitamin, folate, in the body therefore given the close association between folate and riboflavin, it is possible that the combination of these vitamins could reduce BP to a greater extent than riboflavin alone, thereby reducing overall cardiovascular disease risk.

What is the Research aim?

The aim of this study is to investigate the effect of riboflavin and folate supplementation on BP in individuals with a specific genetic risk factor for hypertension.

What the Study involves:

Study duration: 12-months

Screening: Potential participants will be screened for the MTHFR 677C→T polymorphism. Individuals with the MTHFR TT genotype will be eligible to participate in the intervention study.

Duration: two visits per participant at 30 minutes per visit (pre and post intervention).

Measures: At each appointment a blood sample will be taken and blood pressure, pulse wave velocity, pulse wave analysis, height, weight and waist circumference recorded.

Intervention: Participants will be asked to take a supplement containing riboflavin, folic acid, both combined or a placebo capsule. 

PPI Involvement:

PPI involvement was conducted prior to the initiation of the study to assess the attitudes of potential participants to a targeted non-drug treatment option for hypertension.

Who can take part in the Study?

Individuals will be screened and those with the MTHFR TT genotype are eligible to participate in the study.  

Individuals with gastrointestinal, hepatic, renal or haematological disorders, on B-vitamin supplements anticonvulsant therapy or any other drugs known to interfere with folate/B-vitamin metabolism will be excluded from the study.

If you think that you might be suitable and would be interested in taking part, please use the contact information below:

Contact Information:

Dr Catherine Hughes, Principle Investigator

NI Centre for Food and Health Centre for Molecular Biosciences

Ulster University, Cromore Road, Coleraine, BT52 1SA


Phone number: 028 7012 3516

Social Media links:  



NI Clinical Research Facility,
U Floor, Belfast City Hospital,
Lisburn Road, Belfast, BT9 7AB

Tel:+44 (0)28 9504 0342

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