Riboflavin for Mitochondrial Support: Where FMN and FAD Fit in Your Stack

Short answer. Riboflavin (vitamin B2) is the dietary precursor to FMN and FAD, the two flavin cofactors bound inside Complex I and Complex II of the mitochondrial electron transport chain. That places riboflavin upstream of both electron-entry points, at a different node from CoQ10 (a mobile carrier), NAD⁺ precursors (the NADH side), and creatine (short-burst ATP) — which is why riboflavin can be absent from an otherwise complete mitochondrial support stack. Two facts set the limits: oral riboflavin-5’-phosphate is hydrolyzed to free riboflavin before absorption rather than delivered to cells as intact FMN, and riboflavin absorption from a single dose is self-limiting at roughly 27mg.

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

400mg Riboflavin-5’-Phosphate — the freely-soluble, phosphorylated form of vitamin B2 — with magnesium bis-glycinate and a modest dose of D-Ribose: a riboflavin-centered addition to a mitochondrial support stack, and an honest look at what the evidence does and doesn’t show.

BioActive Vitamin B2™ is an activated vitamin B2 supplement from Triquetra Health for performance-driven biohackers and cellular energy optimizers. Most built-out mitochondrial stacks cover NAD⁺ precursors, CoQ10, and creatine. Riboflavin is one we see included less often in the stacks people describe to us — even though it is the dietary precursor to the two flavin cofactors, FMN and FAD, that mitochondrial enzymes depend on. The formula pairs 400mg of riboflavin in the activated Riboflavin-5’-Phosphate form with 50mg of elemental magnesium as a bis-glycinate chelate and 500mg of D-Ribose.

Here’s the honest framing up front, because this audience reads primary literature. Riboflavin genuinely is the precursor to FMN and FAD, and those genuinely are the flavin prosthetic groups at Complex I (FMN) and Complex II (FAD). What the published evidence supports is narrower than the marketing you’ll see elsewhere in this category, and we’d rather tell you where the lines are than get corrected by your own PubMed searches.*

What Do Built-Out Mitochondrial Stacks Usually Miss?

These are common frustrations with many possible causes: sleep, training load, nutrition, stress, and underlying medical issues among them. Flavin cofactor status is one variable worth understanding, not an explanation for any of them.

Your Oura ring shows resting HRV in the mid-range, and it won’t move past a ceiling you’ve stared at for weeks. Sleep looks right, training load is calibrated, nutrition is handled. When the obvious inputs are accounted for, it’s reasonable to ask what your stack doesn’t cover, and riboflavin is one we routinely find missing from otherwise thorough stacks.

The afternoon dip in a long cognitive session is another one people notice. Your nootropic stack is tight, so if focus fades in hour 5 of a 12-hour block, it’s fair to wonder about the cellular energy layer underneath the neurotransmitter layer. We’ll be clear later about what riboflavin can and can’t be said to do here.

Recovery inconsistency between sessions is the third. Some weeks the fatigue clears on schedule and some weeks it doesn’t, and the variable is hard to pin down. Flavin cofactors and ATP-substrate support are two pieces of the recovery picture worth understanding, alongside the bigger levers of sleep, load management, and nutrition.

How Does Riboflavin Compare to CoQ10, NAD⁺ Precursors, and Creatine?

Each point below is about how the standard biohacker stack covers, or skips, parts of mitochondrial biochemistry. None of it is a claim that this product outperforms any of these ingredients.

CoQ10 in the stack. CoQ10 (ubiquinone or ubiquinol) works as a mobile carrier, shuttling electrons between complexes toward Complex III (Turunen, Olsson & Dallner, 2004). It sits at a different point in the chain than the flavin cofactors, which are bound inside Complex I (FMN) and Complex II (FAD) at the electron-entry side. The two occupy different nodes; riboflavin status is simply a separate variable from CoQ10 status, and many stacks address the carrier without addressing riboflavin.

NAD⁺ precursors in the stack. NAD⁺ precursors such as nicotinamide riboside support NAD⁺-dependent pathways, including sirtuins and PARP (Braidy et al., 2019). They feed the NADH side of the chain (Complex I) rather than the FAD side (Complex II). Riboflavin is upstream of the flavin cofactors on both sides. Regulatory status differs across NAD⁺ precursors, so check the current FDA position on any specific one before adding it to a stack.

Standard B-complex or low-dose riboflavin in the stack. Most B-complex products carry riboflavin at 25 to 50mg. That’s above the adult RDA of 1.1 to 1.3mg (NIH ODS) and appropriate for covering dietary needs. BioActive Vitamin B2™ supplies 400mg in the activated R5P form. The difference from a B-complex is one of dose and form specification. We’re not claiming it produces a different physiological outcome, only that it’s a different amount of a different form.

How this differs from standalone high-dose D-Ribose. Standalone ribose products often run 5 to 10g per serving. Our 500mg is a small fraction of that, included for ribose’s role in nucleotide and ATP metabolism rather than as a high-dose substrate load. As you’ll see in the evidence section, the human performance data on ribose is at gram-level doses and is mixed, so we’re deliberately not overselling this component.

What Do FMN and FAD Actually Do in the Mitochondria?

Riboflavin (vitamin B2) is the dietary precursor for FMN and FAD, the two active flavin coenzymes. The human genome encodes about 90 flavin-dependent proteins, of which roughly 84% use FAD and 16% use FMN (Lienhart, Gudipati & Macheroux, 2013). Most catalyze oxidation-reduction reactions in core pathways: the citric acid cycle, beta-oxidation, and the mitochondrial respiratory chain.

Where Do FMN and FAD Sit in the Electron Transport Chain?

The flavin coenzymes are tightly bound prosthetic groups, embedded in their enzymes rather than diffusing freely.

NADH dehydrogenase (Complex I). Its flavin prosthetic group is FMN (Lienhart et al., 2013). FMN accepts electrons from NADH, which begins the proton-pumping cascade across the inner mitochondrial membrane that ultimately drives ATP synthase. Complex I is the largest of the respiratory chain complexes (Sazanov, 2015).

Succinate dehydrogenase (Complex II). Its flavin prosthetic group is FAD (Lienhart et al., 2013). FAD accepts electrons during the succinate-to-fumarate step of the Krebs cycle and feeds them into the ubiquinone pool. Complex II is also the only enzyme that participates in both the Krebs cycle and the electron transport chain (Rutter, Winge & Schiffman, 2010).

Both coenzymes come from riboflavin, which is why riboflavin status is upstream of both entry points.

Does Riboflavin-5’-Phosphate Skip a Conversion Step?

Inside the body, riboflavin is converted in two steps: riboflavin to FMN by riboflavin kinase (ATP-dependent), then FMN to FAD by FAD synthase (Mg²⁺- and ATP-dependent) (Barile et al., 2016; NIH ODS).

It’s tempting to reason that taking the phosphorylated form (R5P, which is chemically FMN) lets you skip that first step. That’s not how oral absorption works, and we want to be straight about it. Dietary and supplemental FMN and FAD are hydrolyzed back to free riboflavin by intestinal phosphatases before they’re absorbed, and NIH notes that the bioavailability of free riboflavin is similar to that of FMN and FAD (NIH ODS; IOM, 1998). So R5P does not arrive at your mitochondria as intact FMN, and we don’t claim it does.

Why we still use R5P is a formulation question, not a delivery-to-tissue claim. Standard riboflavin is only sparingly soluble in water, while riboflavin-5’-phosphate sodium is freely soluble (21 CFR 184.1697). That supports consistent dissolution and a stable, assayable activated-form specification. That’s the honest rationale.

Why 400mg of Riboflavin?

We formulate at 400mg of riboflavin, a generous amount relative to the adult RDA of 1.1 to 1.3mg (NIH ODS). One thing worth knowing: riboflavin absorption is self-limiting. Human pharmacokinetic work put the maximum absorbed from a single dose at roughly 27mg per adult (Zempleni, Galloway & McCormick, 1996), and the body excretes what it doesn’t use. That’s part of why the Food and Nutrition Board set no Tolerable Upper Intake Level for riboflavin (IOM, 1998; NIH ODS). We do not claim 400mg saturates tissue flavin status, and we don’t frame the dose as pharmacological. Expect bright yellow-green urine at this dose. That’s harmless excess riboflavin being excreted (NIH ODS).

What Are the Three Components?

Component 1: Riboflavin-5’-Phosphate, 400mg riboflavin. The activated, freely-soluble form, selected for formulation consistency as described above.

Component 2: Magnesium Bis-glycinate, providing 50mg elemental magnesium. Magnesium is the cofactor FAD synthase uses in the second conversion step, and it’s a nutrient many adults fall short on: NHANES data indicate about 48% of Americans take in less magnesium from food and beverages than the Estimated Average Requirement (NIH ODS). Bis-glycinate is a chelated form thought to be absorbed in part through a dipeptide transport pathway (Schuette et al., 1994); the defensible point about it is tolerability, covered in the evidence section. The 50mg elemental dose is a modest amount, well under the 310 to 420mg adult RDA and under the 350mg supplemental Upper Limit for magnesium (NIH ODS).

Component 3: D-Ribose, 500mg. A five-carbon pentose sugar that forms the backbone of adenine nucleotides (AMP, ADP, ATP) and coenzymes. Ribose can be used by the pentose phosphate pathway to support nucleotide and ATP resynthesis. What the human evidence supports, and where it stops, is in the evidence section; we hold this component to the same honesty standard as the rest.

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

What Does the Research on Riboflavin and D-Ribose Actually Show?

This audience tracks things, so here’s what’s worth tracking and, just as important, what the literature will and won’t back up.

How Is Riboflavin Status Measured?

The established functional marker of riboflavin status is the erythrocyte glutathione reductase activation coefficient (EGRAC); plasma riboflavin can also be measured (NIH ODS). Consumer HRV trends from an Oura ring or WHOOP are not a validated measure of riboflavin status and shouldn’t be read as one. If you want to know your riboflavin status, EGRAC or plasma riboflavin is the answer, not a wearable.

Does Riboflavin Improve Cognitive Performance?

We promised to be clear about this, so here it is: we looked, and there is no controlled trial of riboflavin supplementation on cognitive performance in healthy, riboflavin-replete adults. The brain accounts for about 2% of body weight and roughly 20% of the body’s oxygen consumption (Raichle & Gusnard, 2002), and flavin cofactors are required for mitochondrial energy metabolism in every tissue, brain included. That is biochemistry, not a demonstrated cognitive benefit, and we aren’t going to dress it up as one. If the afternoon dip is what brought you here, riboflavin is not the answer we can evidence.*

What Does the Riboflavin and Exercise Recovery Trial Show?

The most on-point human evidence is Hoffman, Valentino, Stuempfle & Hassid (2017), a double-blind, placebo-controlled trial in runners of the 161-km Western States Endurance Run. Participants took 100mg of riboflavin (or placebo) shortly before the start and again at 90km. The riboflavin group reported lower muscle pain and soreness during and just after the race, and ran significantly faster 400m time trials on days 3 and 5 of recovery.

Read it honestly. The authors call it preliminary work, the sample was small (32 completers), the dose was 100mg given acutely rather than 400mg daily, it used standard riboflavin rather than R5P, and the setting was ultra-endurance. It’s suggestive human evidence in athletes, not proof for this formula. It is, however, a genuinely relevant riboflavin-and-recovery trial in the population this product is written for.

Does D-Ribose Improve Exercise Performance?

Here’s where cherry-picking is a real temptation, so we’ll lay out the whole record. Hellsten, Skadhauge & Bangsbo (2004) found that ribose accelerated the restoration of muscle ATP after intense intermittent training, with ATP back to pre-training levels by 72 hours in the ribose group but not placebo. The same study found no accompanying gain in mean or peak power. Kreider et al. (2003), in 19 trained males at 10g/day for five days, found no change in peak power, average power, torque, fatigue index, lactate, ammonia, glucose, or uric acid, and concluded ribose does not affect anaerobic exercise capacity; one secondary measure, total work output, held steady in the ribose group while declining in placebo (p = .04). Kerksick et al. (2005) found no effect on anaerobic capacity or metabolic markers. Seifert et al. (2017) reported a benefit confined to a lower-fitness subgroup, with no differences in the higher-fitness subgroup, at 10g/day. Cao et al. (2020) reported reduced muscle soreness at 15g/dose in untrained students.

Two things follow. First, ribose has real mechanistic support for ATP-pool restoration but does not reliably improve exercise performance. Second, every one of these trials used gram-level doses; there is no efficacy evidence for ribose at 500mg. We include it for its metabolic role, not as a performance claim.

Is D-Ribose Safe?

A safety note on D-Ribose you should have. Thompson et al. (2014) found that oral D-ribose caused dose-related decreases in serum glucose — up to 26.3 mg/dL, about 30% below baseline, within the first 60 minutes — along with a dose-related insulin peak 15 minutes after dosing, at doses of 2.5 to 10g. Our 500mg serving is well below the lowest dose studied, but if you train fasted, follow a ketogenic protocol, or take any glucose-lowering medication, talk to your healthcare provider before adding a ribose-containing product.*

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

 

Which Studies Support Each Ingredient?

Riboflavin and recovery (human, athletic population). Hoffman, M. D., Valentino, T. R., Stuempfle, K. J., & Hassid, B. V. (2017). A placebo-controlled trial of riboflavin for enhancement of ultramarathon recovery. Sports Medicine – Open, 3(1), 14. DOI: 10.1186/s40798-017-0081-4. Finding: 100mg riboflavin (acute) reduced muscle soreness and sped early 400m recovery after a 161-km race. Limits: preliminary; n=32; acute 100mg; standard riboflavin; ultra-endurance setting.

Riboflavin absorption and dose. Zempleni, J., Galloway, J. R., & McCormick, D. B. (1996). Pharmacokinetics of orally and intravenously administered riboflavin in healthy humans. American Journal of Clinical Nutrition, 63(1), 54–66. DOI: 10.1093/ajcn/63.1.54. Finding: the maximum riboflavin absorbed from a single oral dose is roughly 27mg. This constrains the dose narrative rather than inflating it, and it’s why we don’t claim 400mg saturates anything.

Human flavoproteome and mechanism. Lienhart, W.-D., Gudipati, V., & Macheroux, P. (2013). The human flavoproteome. Archives of Biochemistry and Biophysics, 535(2), 150–162. DOI: 10.1016/j.abb.2013.02.015. Finding: the human genome encodes about 90 flavin-dependent proteins (84% FAD, 16% FMN), including the electron-transport-chain complexes. Mechanistic backbone for the FMN/FAD passages above. For the structural points, see Sazanov (2015) on Complex I and Rutter, Winge & Schiffman (2010) on Complex II; for the two-step conversion pathway, see Barile et al. (2016).

D-Ribose and ATP restoration (mechanism, human). Hellsten, Y., Skadhauge, L., & Bangsbo, J. (2004). Effect of ribose supplementation on resynthesis of adenine nucleotides after intense intermittent training in humans. American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, 286(1), R182–R188. DOI: 10.1152/ajpregu.00286.2003. Finding: at 200 mg/kg body weight three times daily, ribose accelerated muscle ATP restoration but did not improve mean or peak power. That null result is where we let the claim stop.

D-Ribose and performance (null and subgroup results, for honest totality). Kreider, R. B., et al. (2003). IJSNEM, 13(1), 76–86. DOI: 10.1123/ijsnem.13.1.76. Kerksick, C., et al. (2005). IJSNEM, 15(6), 653–664. DOI: 10.1123/ijsnem.15.6.653. Seifert, J. G., Brumet, A., & St Cyr, J. A. (2017). JISSN, 14(1), 47. DOI: 10.1186/s12970-017-0205-8. Cao, W., et al. (2020). JISSN, 17(1), 42. DOI: 10.1186/s12970-020-00371-8. Finding, taken together: no reliable performance benefit. Kreider found no change in peak power, average power, torque, fatigue index, or metabolic markers at 10g/day, with a single secondary measure (total work output) maintained versus placebo (p = .04). Kerksick found nothing on anaerobic capacity or metabolic markers. Seifert’s effect appeared only in the lower-fitness subgroup at 10g/day (a co-author is affiliated with a ribose ingredient supplier). Cao showed reduced soreness at 15g/dose in untrained students. All gram-level doses.

D-Ribose pharmacokinetics and safety. Thompson, J., Neutel, J., Homer, K., Tempero, K., Shah, A., & Khankari, R. (2014). Evaluation of D-ribose pharmacokinetics, dose proportionality, food effect, and pharmacodynamics after oral solution administration in healthy male and female subjects. Journal of Clinical Pharmacology, 54(5), 546–554. DOI: 10.1002/jcph.241. Finding: rapid absorption (Tmax 18–30 min); more-than-proportional Cmax/AUC with dose (metabolic saturation); dose-related serum glucose decreases (up to 26.3 mg/dL, about 30% below baseline) and a dose-related insulin peak at 15 minutes, at 2.5–10g. Authors are affiliated with a ribose supplier (RiboCor).

Magnesium form: absorption and tolerability. Schuette, S. A., Lashner, B. A., & Janghorbani, M. (1994). Bioavailability of magnesium diglycinate vs magnesium oxide in patients with ileal resection. Journal of Parenteral and Enteral Nutrition (JPEN), 18(5), 430–435. DOI: 10.1177/0148607194018005430. Finding: overall absorption was similar for diglycinate and oxide (23.5% vs 22.8%); the chelate was better tolerated by all patients and absorbed significantly better only in the subset with the most impaired absorption. Population was ileal-resection patients. Walker, A. F., Marakis, G., Christie, S., & Byng, M. (2003). Mg citrate found more bioavailable than other Mg preparations in a randomised, double-blind study. Magnesium Research, 16(3), 183–191.

Finding: in 46 healthy adults over 60 days at 300mg elemental, organic forms (citrate and amino-acid chelate) showed greater absorption than oxide, with citrate best; oxide did not differ from placebo. The defensible statement is that chelated magnesium was better tolerated than oxide in the one clinical comparison available, and that organic magnesium forms are absorbed at least as well as oxide in healthy adults. Note that Walker measured absorption markers, not tolerability, and that its best-performing form was citrate. We do not claim bis-glycinate is the best-absorbed form.

Riboflavin biochemistry and status. Powers, H. J. (2003). Riboflavin (vitamin B-2) and health. American Journal of Clinical Nutrition, 77(6), 1352–1360. DOI: 10.1093/ajcn/77.6.1352. Ashoori, M., & Saedisomeolia, A. (2014). Riboflavin (vitamin B₂) and oxidative stress: a review. British Journal of Nutrition, 111(11), 1985–1991. DOI: 10.1017/S0007114514000178. Powers covers riboflavin dietary sources, status, and health context; Ashoori covers FAD-dependent glutathione reductase. Ashoori is a narrative review drawing largely on animal and deficiency-model work; it does not establish an antioxidant benefit from supplementation in trained adults.

Safety and regulatory. EFSA (2018). Safety of D-ribose as a novel food. EFSA Journal, 16(5), 5265. DOI: 10.2903/j.efsa.2018.5265. Finding: D-ribose is safe for the general population up to 36 mg/kg body weight per day (about 2,500mg for a 70kg adult); EFSA declined to establish safety at the higher intakes the applicant proposed. Our 500mg serving sits below that reference level. Regulatory status of the ingredients: riboflavin and riboflavin-5’-phosphate sodium are affirmed GRAS for food use (21 CFR 184.1695 and 184.1697).

D-ribose has been the subject of GRAS notices to which FDA responded “no questions” (GRN 100, GRN 243). Magnesium bisglycinate is a long-marketed dietary ingredient. GRAS status applies to food use and is not FDA approval or endorsement of any supplement. IOM/NIH: no Tolerable Upper Intake Level is set for riboflavin because adverse effects from high intakes haven’t been reported; NIH also notes that the absence of a UL doesn’t prove high intakes are without effect, and advises caution about excessive amounts (NIH ODS).

Where Does Riboflavin Sit in a Mitochondrial Stack?

Riboflavin supplies the flavin cofactors (FMN and FAD) used inside Complex I and Complex II. That’s a different position in the chain from the ingredients most stacks already include. The table describes where each sits; it isn’t a claim that this product outperforms any of them.

 

 

The practical read: if your stack already covers the carrier (CoQ10), the NADH side (NAD⁺ precursors), and short-burst ATP (creatine), riboflavin is a distinct input that those three don’t supply. That’s the case for looking at it. It is not a case that riboflavin does something those ingredients fail to do.

Riboflavin Stack Integration: Common Questions

Can I take BioActive Vitamin B2™ with my existing CoQ10, NAD⁺ precursor, and creatine?

Yes. Riboflavin is a water-soluble vitamin and a normal part of the diet; it occupies a different node than those ingredients. Add it alongside your existing stack rather than replacing anything. As always, talk to your healthcare provider about your specific regimen, especially if you take medications or have a health condition.*

Does R5P get to my cells as FMN and skip a conversion step?

No, and it’s worth being clear about this because a lot of category marketing implies otherwise. Oral R5P (and FAD) are hydrolyzed to free riboflavin before absorption, and oral bioavailability is similar to plain riboflavin (NIH ODS; IOM, 1998). We use R5P for its solubility and activated-form specification, not because it delivers FMN intact.*

Why 400mg when the riboflavin RDA is about 1.3mg?

It’s a generous amount by design. Keep in mind that riboflavin absorption is self-limiting (roughly 27mg per single dose; Zempleni et al., 1996), the excess is excreted (hence the bright-yellow urine), and no Upper Limit is set for riboflavin (NIH ODS). We’re not claiming 400mg saturates tissue flavin status.*

Why only 500mg of D-Ribose when other products use 5g?

Because the honest reading of the ribose literature doesn’t support a high-dose performance claim (see the evidence section), and higher oral doses can transiently lower blood glucose. We include a modest amount for ribose’s role in nucleotide metabolism, not as a substrate-loading strategy.*

Does riboflavin status vary between people?

It does, mostly with diet. Milk and dairy products are the largest contributors to riboflavin intake in Western diets, so lower-dairy eating patterns may supply less (Powers, 2003; NIH ODS). If you want to check your status, EGRAC or plasma riboflavin is the measure (NIH ODS).*

[FAQ SCHEMA REQUIRED — Stack Integration FAQ. When building FAQPage schema, copy the final visible Q&A text verbatim and append the full FDA disclaimer inside each answer that carries a structure/function claim.]

What Does the Evidence Actually Support?

Here’s what survives a careful read, and it isn’t nothing. Riboflavin really is the precursor to FMN and FAD, and those really are the flavin prosthetic groups at Complex I and Complex II; about 90 human flavin-dependent proteins depend on them (Lienhart et al., 2013). Riboflavin really is the piece we see left out most often. There’s a real, placebo-controlled trial in athletes showing acute riboflavin reduced muscle soreness and sped early functional recovery after a 161-km race (Hoffman et al., 2017). Chelated magnesium really was better tolerated than oxide in the one clinical comparison available (Schuette et al., 1994), and a 60-day RCT in 46 healthy adults found organic magnesium forms better absorbed than oxide, which did not differ from placebo (Walker et al., 2003). And ribose really does accelerate muscle ATP restoration in humans (Hellsten et al., 2004), even though that doesn’t translate into more power output.

That’s a coherent, well-cited story about a nutrient the category overlooks. It’s a smaller claim than “the completion piece your stack is missing,” and it’s one that holds up to an FTC read and a reader with PubMed open.

Learn More About BioActive Vitamin B2™ →

60-day satisfaction guarantee (see terms on the product page). Third-party tested by [laboratory name]; batch certificates of analysis available at [COA URL]. Manufactured in a cGMP facility. Consult a healthcare provider before modifying supplement protocols, particularly with pre-existing conditions or medication use.*

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Individual results may vary.

What’s in BioActive Vitamin B2™? Ingredient Specifications

Riboflavin-5’-Phosphate (sodium), providing 400mg riboflavin. Activated, phosphorylated form of vitamin B2 (chemically FMN). Selected for its aqueous solubility and stable activated-form assay (21 CFR 184.1697). Processed like dietary flavins in the digestive tract before absorption; we make no intact-FMN delivery claim.

Magnesium Bis-glycinate, providing 50mg elemental magnesium. Chelated magnesium, thought to be absorbed in part via a dipeptide transport pathway; better tolerated than oxide (Schuette et al., 1994), and organic magnesium forms were better absorbed than oxide in healthy adults (Walker et al., 2003).

[HOLD FOR COA: The elemental-magnesium figure and the chelate weight must match the batch certificate of analysis before publish. Pure magnesium bisglycinate is ~14.1% magnesium by weight, so 50mg elemental implies either a larger chelate quantity than a simple 278mg or a buffered/blended material. Publish only the figures the COA supports, and if the material is buffered, state that: “Magnesium bisglycinate (buffered), Xmg providing 50mg elemental magnesium.”]

D-Ribose, 500mg. Five-carbon pentose sugar; a component of adenine nucleotides. Included for its metabolic role; see the evidence and safety notes above. EFSA assessed D-ribose as safe up to 36 mg/kg body weight per day (EFSA, 2018); 500mg is well below that reference level for adults.

[Specification note: publish ≥98% purity, the third-party testing lab name or COA link, and the guarantee terms only as supported by internal documents.]

More Questions About Riboflavin and Flavin Cofactors

What’s the relationship between riboflavin and glutathione reductase?

Glutathione reductase is an FAD-dependent enzyme that regenerates reduced glutathione (GSH) from its oxidized form (Ashoori & Saedisomeolia, 2014; Lienhart et al., 2013). This is established biochemistry. We’re not extending it to a training-recovery or antioxidant benefit from supplementation, because the review evidence on that point draws largely on animal and deficiency models.*

What biomarkers show riboflavin status?

The erythrocyte glutathione reductase activation coefficient (EGRAC) is the established functional marker; plasma riboflavin can also be measured (NIH ODS). Wearable HRV is not a measure of riboflavin status.*

Is this product for any medical condition?

No. BioActive Vitamin B2™ is a dietary supplement for general nutritional support. It is not intended to diagnose, treat, cure, or prevent any disease or condition. For any medical concern, including injury recovery, see a qualified clinician, and consult them before adding any supplement.*

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Individual results may vary.

Scientific References & Citations

All sources were located on PubMed and/or via DOI and checked against the published record for author, journal, volume, issue, and page accuracy. Last citation audit: [DATE].

Ashoori, M., & Saedisomeolia, A. (2014). Riboflavin (vitamin B₂) and oxidative stress: A review. British Journal of Nutrition, 111(11), 1985–1991. https://doi.org/10.1017/S0007114514000178

Barile, M., Giancaspero, T. A., Leone, P., Galluccio, M., & Indiveri, C. (2016). Riboflavin transport and metabolism in humans. Journal of Inherited Metabolic Disease, 39(4), 545–557. https://doi.org/10.1007/s10545-016-9950-0

Braidy, N., Berg, J., Clement, J., Khorshidi, F., Poljak, A., Jayasena, T., Grant, R., & Sachdev, P. (2019). Role of nicotinamide adenine dinucleotide and related precursors as therapeutic targets for age-related degenerative diseases: Rationale, biochemistry, pharmacokinetics, and outcomes. Antioxidants & Redox Signaling, 30(2), 251–294. https://doi.org/10.1089/ars.2017.7269

Cao, W., Qiu, J., Cai, T., Yi, L., Benardot, D., & Zou, M. (2020). Effect of D-ribose supplementation on delayed onset muscle soreness induced by plyometric exercise in college students. Journal of the International Society of Sports Nutrition, 17(1), 42. https://doi.org/10.1186/s12970-020-00371-8

European Food Safety Authority Panel on Nutrition, Novel Foods and Food Allergens. (2018). Safety of D-ribose as a novel food pursuant to Regulation (EU) 2015/2283. EFSA Journal, 16(5), 5265. https://doi.org/10.2903/j.efsa.2018.5265

Hellsten, Y., Skadhauge, L., & Bangsbo, J. (2004). Effect of ribose supplementation on resynthesis of adenine nucleotides after intense intermittent training in humans. American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, 286(1), R182–R188. https://doi.org/10.1152/ajpregu.00286.2003

Hoffman, M. D., Valentino, T. R., Stuempfle, K. J., & Hassid, B. V. (2017). A placebo-controlled trial of riboflavin for enhancement of ultramarathon recovery. Sports Medicine – Open, 3(1), 14. https://doi.org/10.1186/s40798-017-0081-4

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These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Individual results may vary based on baseline riboflavin status, training volume, stack composition, and measurement methodology. Consult a healthcare provider before modifying supplement protocols, particularly with pre-existing conditions or medication use.