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Vitamin B2

Riboflavin is an essential vitamin that is required for some enzymes in the body to act normally. Supplementation of riboflavin is not outright required with a good diet, but may serve some benefits for cardiovascular health in genetically susceptible people.

Our evidence-based analysis on vitamin b2 features 104 unique references to scientific papers.

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Summary of Vitamin B2

Primary information, health benefits, side effects, usage, and other important details

Vitamin B2 refers to the molecule known as riboflavin, which is a vitamin because it can produce two cofactors abbreviated as FAD and FMN. Some proteins in the body are dependent on these cofactors to function optimally and dietary riboflavin is the sole provider of FAD and FMN for these enzymes, which are called flavoproteins since FAD and FMN are 'flavins' and work in concert with these proteins.

True deficiencies of riboflavin result in a condition known as ariboflavinosis, which is fairly rare in first world countries but characterized by various ailments of mucuous membranes (mouth and throat) and the skin as well as eye problems. Suboptimal deficiencies are somewhat prevalent although not common aside from a few groups, and for the most part do not result in any major health-threatening conditions.

Groups that would benefit from riboflavin supplementation include adolescent and young adult women, particularly in the UK where riboflavin is not fortified in food to as high a level as in the US and Canada, and the elderly which tend to have less than optimal intakes of riboflavin.

Beyond merely supporting a good riboflavin status, supplementation has a possible benefit for cardiovascular health in a certain population. People who have two copies of a certain gene, known as MTHFR 677TT, have a condition where homocysteine is abnormally elevated due to defects in folate metabolism. These people may experience reductions in blood pressure and homocysteine when riboflavin is supplemented at a low dose. Higher doses of riboflavin (at around 400mg taken in split doses throughout the day) may also have a therapeutic effect for migraines.

Overall, riboflavin is a vitamin which someone could not ingest enough of if their diet is poor, yet a better diet could correct this. Supplementation is never mandatory but is likely prudent for people who are confirmed to be MTHFR 677TT or for anemics on iron repletion therapy (where optimizing riboflavin intake would aid the utility of supplemental iron).

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How to Take

Medical Disclaimer

Recommended dosage, active amounts, other details

Riboflavin, for the purpose of maintaining a sufficient riboflavin status in the body, can be supplemented at a relatively low dose of 1-2mg daily to support riboflavin stores in the body. Higher dose (4mg) may increase stores more rapidly but may perform equally over the long term, and these doses are also what should be taken for the purpose of reducing homocysteine concentrations.

For the purpose of reducing migraines, while the optimal dose is not yet confirmed many studies use a total daily dose of 400mg riboflavin divided into various doses throughout the day; riboflavin at these doses (50mg or more) should be taken with food, a dosing modification which does not apply to lower dose supplementation which is fine on an empty stomach.

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Human Effect Matrix

The Human Effect Matrix looks at human studies (it excludes animal and in vitro studies) to tell you what effects vitamin b2 has on your body, and how strong these effects are.
Grade Level of Evidence
Robust research conducted with repeated double-blind clinical trials
Multiple studies where at least two are double-blind and placebo controlled
Single double-blind study or multiple cohort studies
Uncontrolled or observational studies only
Level of Evidence
? The amount of high quality evidence. The more evidence, the more we can trust the results.
Outcome Magnitude of effect
? The direction and size of the supplement's impact on each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.
Consistency of research results
? Scientific research does not always agree. HIGH or VERY HIGH means that most of the scientific research agrees.
Notes
grade-b Notable Moderate See all 5 studies
Homocysteine appears to be reduced to a large degree at 1.6mg, but this effect is exclusive to subjects with a specific genetic mutation known as MTHFR 677TT (two copies of MTHFR 677C->T).
grade-b Notable Moderate See all 7 studies
Riboflavin supplementation appears to be quite effective in reducing migraine frequency based on preliminary research. The effect of riboflavin on intensity is still undetermined, and the optimal dose is not known as while most studies use 400mg one found similar benefits with 25mg.
grade-c Minor Very High See all 3 studies
There appears to be a reduction in blood pressure in the same subjects who have a reduction in homocysteine, those with the MTHFR 677TT genetic mutation.
grade-c - - See study
Antioxidant enzymes do not appear to be increased in red blood cells in response to 10mg riboflavin supplementation.
grade-c - - See study
C-reactive protein concentrations in serum do not appear to be affected with supplementation of riboflavin.
grade-c - - See study
Despite the benefits of riboflavin supplementation towards hemoglobin content in people who have low riboflavin status, ferritin concentrations are not affected.
grade-c - - See study
Symptoms of multiple sclerosis do not appear to be affected by supplementation of 10mg riboflavin relative to placebo.
grade-c - - See study
The uric acid/urate balance is not affected by supplementation of riboflavin.

Studies Excluded from Consideration

  • Confounded with other dietary supplements[1]

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Things to Note

Other Functions:

Also Known As

Riboflavin

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Click here to see all 104 references.