Key messages
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The effect of oral riboflavin (vitamin B2) supplements on blood pressure is uncertain.
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Large, well-conducted trials are needed to assess the effect of riboflavin on blood pressure lowering.
What is blood pressure?
Blood pressure is the pressure of the circulating blood against the blood vessel walls. Systolic blood pressure is the highest pressure during a heartbeat, and diastolic blood pressure is the lowest pressure between heartbeats. Higher systolic and diastolic blood pressure increases the risk for heart disease and stroke.
What is riboflavin?
Riboflavin is a vitamin (vitamin B2), found naturally in many foods such as milk and milk products, yeast extracts, eggs, liver and kidney. Riboflavin can also be taken as a supplement.
What did we want to find out?
We wanted to find out whether taking riboflavin supplements lowers blood pressure.
What did we do?
We searched for studies in adults that compared the effects of riboflavin to a placebo (“dummy” pills) on blood pressure. We made judgements about the quality of the studies we included and summarised their results. We then rated our confidence in the evidence.
What did we find?
We included four studies with a total of 374 people. The evidence is very uncertain about the effect of riboflavin on systolic blood pressure and diastolic blood pressure. The evidence suggests that riboflavin may result in little to no difference in adverse events.
How current is the evidence?
We searched for all available evidence up to October 2024.
What are the limitations of the evidence?
Our confidence in the evidence that riboflavin lowers blood pressure was very low, because the results from some of the people that took part in the included studies were not reported and because the included studies were relatively small.
What does this mean?
The effect of riboflavin on blood pressure is very uncertain. Further, high quality, large studies are needed to determine whether riboflavin lowers blood pressure.
Pročitajte cijeli sažetak
Ciljevi
To assess the benefits and harms of riboflavin supplements compared to placebo or no additional treatment for lowering systolic and diastolic blood pressure.
Metode pretraživanja
We searched the Cochrane Hypertension Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE, Ovid Embase, Clarivate Web of Science, Clarivate Food Science & Technology Abstracts and two clinical trials registries. There were no restrictions on language, publication year, or publication status. The latest search date was 24 October 2024. We also handsearched the reference lists of included studies.
Zaključak autora
The evidence for the effect of oral riboflavin supplements on systolic and diastolic blood pressure is very uncertain. The evidence comes from four RCTs, three of which had an overall high risk of bias. Large, well-conducted trials are needed for high-certainty evidence of the effect of riboflavin for blood pressure lowering.
Funding
KEB was supported by a Sir Charles Hercus Health Research Fellowship from the Health Research Council (Grant number: 19/110) and a Senior Heart Foundation fellowship from the Heart Foundation of New Zealand, supported in part by the GR Winn Trust (Grant number: 3728679).
Registration
Protocol (2023): DOI: 10.1002/14651858.CD015464.
