Quick summary

Riboflavin-5-Phosphate (also known as FMN or flavin mononucleotide) is the active, water-soluble coenzyme form of vitamin B2. It plays a critical role in various biological oxidation-reduction reactions essential for cellular energy metabolism. As the coenzyme derivative of vitamin B2, it participates directly in electron transport and metabolic redox processes.

What is it?

Riboflavin-5-Phosphate is a phosphorylated derivative of riboflavin (vitamin B2) and represents its biologically active form in the body. It belongs to the vitamin B complex group and is water-soluble. This compound serves as a coenzyme widely involved in enzymatic reactions, primarily those mediating electron transfer for energy production. Common alternative names for Riboflavin-5-Phosphate include FMN (flavin mononucleotide). It is distinct from riboflavin itself, as it is the form that interacts directly within metabolic pathways.

Main functions in the body

  • Acts as a coenzyme in energy production pathways involving oxidation-reduction (redox) reactions
  • Supports critical redox reactions in cellular metabolism, facilitating electron transport

Recommended intake and upper limit

Specific recommended daily intake (RDA) or adequate intake (AI) values for Riboflavin-5-Phosphate separately from vitamin B2 are not provided. Intake guidelines generally refer to vitamin B2 as a whole, since Riboflavin-5-Phosphate functions as its active form in the body.

Values for vitamin B2 vary by age, sex, and life stage; consult authoritative sources for individual recommendations. Currently, there are no established upper intake levels (UL) specifically for Riboflavin-5-Phosphate. For dosing and safety parameters, use vitamin B2 recommendations as a reference.

Note
No unique intake guidelines or tolerable upper limits exist specifically for Riboflavin-5-Phosphate; follow vitamin B2 recommendations.

Best food sources

There is no direct data on food sources containing Riboflavin-5-Phosphate per se, as it is produced metabolically from vitamin B2. Foods rich in vitamin B2 include dairy products, eggs, green leafy vegetables, nuts, and enriched cereals. Riboflavin, once ingested, is converted enzymatically within the body to Riboflavin-5-Phosphate to carry out its biological functions.

Deficiency: causes, symptoms and risk groups

Deficiency symptoms and risk groups relate to overall vitamin B2 insufficiency, not to Riboflavin-5-Phosphate specifically. Since Riboflavin-5-Phosphate is the active form derived from vitamin B2, inadequate dietary intake or malabsorption of vitamin B2 can reduce its availability, potentially impairing metabolic functions dependent on this coenzyme.

No unique clinical signs have been attributed solely to Riboflavin-5-Phosphate deficiency separate from vitamin B2 deficiency.

Supplement forms

  • Riboflavin-5-Phosphate is available as an active coenzyme form supplement, often used to provide the bioactive vitamin B2 form directly.

Potential benefits: what does the evidence say?

General metabolism

Strong evidence supports that Riboflavin-5-Phosphate is the essential coenzyme form of vitamin B2 required for electron transport and energy metabolism. Its supplementation delivers the biologically active form directly, potentially aiding enzyme functions involving redox reactions.

However, available data do not support unique benefits or health claims for Riboflavin-5-Phosphate distinct from general vitamin B2 roles.

Side effects and toxicity

There is insufficient evidence documenting common side effects or toxicity specific to Riboflavin-5-Phosphate supplementation. No established upper intake levels and no reported adverse effects have been identified at typical supplemental doses.

Drug and nutrient interactions

No specific drug-nutrient interactions involving Riboflavin-5-Phosphate have been identified separately from vitamin B2. As with all B vitamins, interactions may occur with certain medications affecting vitamin absorption or metabolism, but data on Riboflavin-5-Phosphate alone are lacking.

Who should be careful?

People who are pregnant, breastfeeding, have underlying medical conditions or who use medications should consult a healthcare professional before beginning any supplementation, including Riboflavin-5-Phosphate. There is insufficient clinical evidence regarding special population safety.

Frequently asked questions

  • Is Riboflavin-5-Phosphate different from vitamin B2?
    Yes, Riboflavin-5-Phosphate is the active coenzyme form of vitamin B2 (riboflavin) utilized in energy metabolism.
  • Are there specific intake recommendations for Riboflavin-5-Phosphate?
    No distinct recommendations exist; follow vitamin B2 intake guidelines for overall adequacy.
  • Can I get Riboflavin-5-Phosphate from food?
    Foods provide vitamin B2, which the body converts enzymatically into Riboflavin-5-Phosphate.
  • Does Riboflavin-5-Phosphate have any unique health claims?
    Currently, no EU-authorized or other health claims exist separate from vitamin B2 benefits.
  • Is it safe to use Riboflavin-5-Phosphate supplements?
    Supplements appear safe at typical doses, but clinical data are limited; consult healthcare providers if uncertain.

Evidence limitations

  • No specific human clinical studies assess Riboflavin-5-Phosphate supplementation independently from general vitamin B2 research.
  • Lack of clinical trial data addressing special therapeutic uses or conditions involving Riboflavin-5-Phosphate.
  • Absence of EU-authorized health claims for this specific form.

References

Last reviewed

June 2024

Disclaimer

This information is provided for educational purposes only and is not medical advice. The scientific evidence relating to Riboflavin-5-Phosphate is primarily tied to its function as vitamin B2’s active form. Individuals who are pregnant, breastfeeding, have medical conditions, or are taking medications should consult a healthcare professional before starting any supplement regimen.