Riboflavin
Riboflavin/Drug Interactions:
AlcoholAlcohol: According to Poschl, deficiencies of riboflavin may further enhance alcohol-associated carcinogenesis (200; 201). Alzheimer's agentsAlzheimer's agents: According to secondary sources, riboflavin may interact with Alzheimer's agents.AntibioticsAntibiotics: According to secondary sources, long-term use of antibiotics may deplete vitamin B levels, including riboflavin. Riboflavin either alone or in combination with other B vitamins should be taken at different times from the antibiotic tetracycline (202). AnticholinergicsAnticholinergics: The effect of an anticholinergic agent on riboflavin absorption in humans has been discussed (203). Further information is lacking. AnticonvulsantsAnticonvulsants: In human research, patients on various antiepileptic agents had decreased riboflavin status (204). Supplementation with riboflavin in patients with low riboflavin status and on antiepileptic drugs did not improve thyroid function (205). Antifungal agentsAntifungal agents: According to a review, a reduction in Candida albicans of the eye was observed following photodynaminc therapy with higher concentrations of photosensitizers, such as riboflavin (206). AntihelminthicsAntihelminthics: According to secondary sources, riboflavin may interact with antihelminthic agents.Antimalarial agentsAntimalarial agents: Low riboflavin levels have been associated with use of antimalaria agents (207; 208; 209). AntineoplasticsAntineoplastics: In vitro, riboflavin resulted in a reduction in the prevalence of micronuclei in esophageal cells (210). In human research, a treatment plan containing riboflavin, coenzyme Q10, and niacin, resulted in a decrease in breast cancer tumor markers and in angiogenesis markers and cytokines (58; 211; 212; 213). In epidemiological research, plasma riboflavin was inversely associated with risk of advanced colorectal adenoma lesions (214) and oral and pharyngeal cancer risk (215). In vitro, riboflavin reduced cisplatin-induced genotoxicity (216) and methotrexate may compete with riboflavin for entry into the cell (217). According to a review, doxorubicin may bind 1:1 with riboflavin and prevent its binding to tissues (218). In human research, supplementation with four nutrients, including riboflavin, decreased the frequency of micronuclei as well as DNA adducts (219). Antithyroid agentsAntithyroid agents: In human research, use of antithyroid therapy resulted in decreased riboflavin status (220). In anorectic girls undergoing a refeeding program, tri-iodothyronine concentrations (low) were negatively correlated with plasma riboflavin (221). Bone agentsBone agents: In epidemiological research, enhanced riboflavin intake was correlated with increased bone mineral density in individuals with the TT genotype (homozygous mutant) of the methylenetetrahydrofolate reductase (MTHFR) gene (222). Cardiovascular agentsCardiovascular agents: In epidemiological research, enhanced riboflavin status resulted in lowered levels of homocysteine (a cardiovascular disease risk factor) in individuals with the TT genotype (homozygous mutant) of the MTHFR gene (223; 157; 224), and lower riboflavin status was associated with increased plasma homocysteine (225; 226). ChlorpromazineChlorpromazine: According to a review, chlorpromazine increased riboflavin excretion in the urine (227). ContraceptivesContraceptives: According to reviews, riboflavin levels in plasma and erythrocytes may decrease with high-dose oral contraceptive use, resulting in increased requirements (228; 229; 230; 231; 232; 233; 234; 235). Joshi et al. determined that riboflavin levels were not further decreased in riboflavin-deficient women using oral contraceptives, but were in women with adequate status (236). The physiological significance of these studies is not clear, as controlling for dietary riboflavin intake and reducing estrogen levels may remove this effect. Dermatologic agentsDermatologic agents: According to secondary sources, possible reactions to very high doses of riboflavin include itching.Diuretics, thiazideDiuretics, thiazide: In human research, use of diuretics increased riboflavin excretion (237). Exercise performance enhancement agentsExercise performance enhancement agents: In human research, restricted intake of riboflavin significantly decreased aerobic power, onset of blood lactate accumulation, and oxygen consumption (71; 238). Gastrointestinal agentsGastrointestinal agents: In human research, diarrhea has been reported following riboflavin supplementation (140; 144). Iron saltsIron salts: Iron and riboflavin improved the papillary threshold in vitamin A-supplemented pregnant women in Nepal (239). In human research, addition of riboflavin improved the effect of iron and folate with respect to hemoglobin levels (240). In human research, riboflavin therapy improved efficiency of iron utilization (241). This has been the topic of reviews (242; 243). Neurologic herbs and supplementsNeurologic herbs and supplements: According to secondary sources, possible reactions to very high doses of riboflavin include numbness and burning or prickling sensations.PhenobarbitalPhenobarbital: In animal and in vitro research, dietary intake or status of riboflavin may play a role in phenobarbital metabolism and activity (244; 245; 246; 247). PhenothiazinesPhenothiazines: In rat tissues, chlorpromazines inhibited flavokinase, the enzyme that transforms riboflavin into its functionally active cofactor form (248). According to a review, chlorpromazine increased riboflavin excretion in the urine (227). PhotosensitizersPhotosensitizers: According to secondary sources, riboflavin has photosensitizing properties.ProbenecidProbenecid: Probenecid altered the renal clearance of riboflavin in human research (249; 250). TamoxifenTamoxifen: In women with breast cancer, tamoxifen use increased riboflavin status (251). It is unclear if initial riboflavin levels were due to treatment with doxorubicin chemotherapy. Tricyclic antidepressantsTricyclic antidepressants: In rat tissues, amitriptyline and imipramine inhibited flavokinase, the enzyme that transforms riboflavin into its functionally active cofactor form (248). In human research, riboflavin, in combination with other B vitamins, increased the antidepressant effect of tricyclic antidepressant treatment (252). According to secondary sources, riboflavin deficiency has occurred following use of amitriptyline. Riboflavin/Herb/Supplement Interactions:
Alzheimer's herbs and supplementsAlzheimer's herbs and supplements: According to secondary sources, riboflavin may interact with Alzheimer's agents.AntibacterialsAntibacterials: According to secondary sources, long-term use of antibiotics may deplete vitamin B levels, including riboflavin. Riboflavin, either alone or in combination with other B vitamins, should be taken at different times from the antibiotic tetracycline (202). Anticholinergic herbs and supplementsAnticholinergic herbs and supplements: The effect of an anticholinergic agent on riboflavin absorption in man has been discussed (203). Further information is lacking. AnticonvulsantsAnticonvulsants: In human research, patients on various antiepileptic agents had decreased riboflavin status (204). Supplementation with riboflavin in patients with low riboflavin status and on antiepileptic drugs did not improve the thyroid function (205). AntidepressantsAntidepressants: In rat tissues, amitriptyline and imipramine inhibited flavokinase, the enzyme that transforms riboflavin into its functionally active cofactor form (248). In human research, riboflavin, in combination with other B vitamins, increased the antidepressant effect of tricyclic antidepressant treatment (252). According to secondary sources, riboflavin deficiency has occurred following use of amitriptyline. Antifungal herbs and supplementsAntifungal herbs and supplements: According to a review, a reduction in Candida albicans of the eye was observed following photodynaminc therapy with higher concentrations of photosensitizers, such as riboflavin (206). AntihelminthicsAntihelminthics: According to secondary sources, riboflavin may interact with antihelminthic agents.Antimalarial herbs and supplementsAntimalarial herbs and supplements: Low riboflavin levels have been associated with use of antimalarial herbs and supplements (207; 208; 209). AntineoplasticsAntineoplastics: In vitro, riboflavin resulted in a reduction in the prevalence of micronuclei in esophageal cells (210). In human research, a treatment plan containing riboflavin, coenzyme Q10, and niacin resulted in a decrease in breast cancer tumor markers and in angiogenesis markers and cytokines (58; 211; 212; 213). In epidemiological research, plasma riboflavin was inversely associated with risk of advanced colorectal adenoma lesions (214) and oral and pharyngeal cancer risk (215). In vitro, riboflavin reduced cisplatin-induced genotoxicity (216) and methotrexate may compete with riboflavin for entry into the cell (217). B vitaminsB vitamins: In human research, addition of riboflavin to folate supplementation resulted in a further increase in MTHFR activity (253), and inclusion of riboflavin with folate supplementation has been studied with respect to homocysteine lowering, although not all studies have been positive (254; 255). Addition of riboflavin improved the effect of iron and folate with respect to hemoglobin levels (240). In human research, folic acid 400mcg daily appeared to exacerbate a tendency toward riboflavin deficiency (225). Pyridoxine and riboflavin are interconnected with respect to metabolism and effects in the body (256; 257). In human research, riboflavin supplementation in riboflavin-deficient women resulted in a marked increase in the activity of pyridoxamine phosphate: oxygen oxidoreductase (deaminating) (258). As are folate and pyridoxal, riboflavin is also involved in the metabolism of niacin. This was discussed by Wittmann with respect to the clinical and biochemical effects of riboflavin and nicotinamide supplementation (259). The interrelationship between the B vitamins has been reviewed (260). Bone herbs and supplementsBone herbs and supplements: In epidemiological research, enhanced riboflavin intake was correlated with increased bone mineral density in individuals with the TT genotype (homozygous mutant) of the methylenetetrahydrofolate reductase (MTHFR) gene (222). Boric acidBoric acid: According to a review, boric acid forms a complex with the polyhydroxyl ribitol side chain of riboflavin and increases its water solubility, resulting in increased excretion of riboflavin within the first 24-48 hours (227). Cardiovascular herbs and supplementsCardiovascular herbs and supplements: In epidemiological research, enhanced riboflavin status resulted in lowered levels of homocysteine in individuals with the TT genotype (homozygous mutant) of the MTHFR gene (223; 157; 224), and lower riboflavin status was associated with increased plasma homocysteine (225; 226). DiureticsDiuretics: In human research, use of diuretics increased riboflavin excretion (237). Exercise performance enhancement herbs and supplementsExercise performance enhancement herbs and supplements: In human research, restricted intake of riboflavin resulted in a significant decrease in aerobic power, onset of blood lactate accumulation, and oxygen consumption (71; 238). Gastrointestinal herbs and supplementsGastrointestinal herbs and supplements: In human research, diarrhea has been reported following riboflavin supplementation (140; 144). Hormonal herbs and supplementsHormonal herbs and supplements: According to reviews, riboflavin levels in plasma and erythrocytes may decrease with high-dose oral contraceptive use, resulting in increased requirement (228; 229; 230; 231; 232). Joshi et al. determined that riboflavin levels were not further decreased in riboflavin-deficient women using oral contraceptives, but were in women with adequate status (236). The physiological significance of these studies is not clear. IronIron: Iron and riboflavin improved the papillary threshold in vitamin A-supplemented pregnant women in Nepal (239). In human research, addition of riboflavin improved the effect of iron and folate with respect to hemoglobin levels (240). In human research, riboflavin therapy improved efficiency of iron utilization (241). This has been the topic of reviews (242; 243). Lipoic acidLipoic acid: In human research, lipoic acid resulted in disturbed utilization of riboflavin (261). Further details are lacking at this time. Neurologic herbs and supplementsNeurologic herbs and supplements: According to secondary sources, possible reactions to very high doses of riboflavin include numbness and burning or prickling sensations.PhotosensitizersPhotosensitizers: According to secondary sources, riboflavin has photosensitizing properties.ProbioticsProbiotics: In human research, the plasma concentration of flavin adenine dinucleotide (FAD) decreased significantly after consuming probiotics or yogurt, and plasma concentrations of flavin mononucleotide (FMN) and free riboflavin increased (262). Thyroid agentsThyroid agents: In human research, use of antithyroid therapy resulted in decreased riboflavin status (220). In anorectic girls undergoing a refeeding program, tri-iodothyronine concentrations (low) were negatively correlated with plasma riboflavin (221). Vitamin AVitamin A: Iron and riboflavin improved the papillary threshold in vitamin A-supplemented pregnant women in Nepal (239). Vitamin CVitamin C: In epidemiological research, there was a significant association of percent change in vitamin C with intake of riboflavin (263). ZincZinc: In epidemiological research, there was a significant association of percent change in plasma zinc with intake of riboflavin (263). Riboflavin/Food Interactions:
GeneralGeneral: Refeeding of anorectic patients resulted in an increase in erythrocyte riboflavin status (221). Incorporating healthy foods into the diet increased riboflavin status (264). During weaning, traditional foods may be preferable to fortified manufactured baby foods in terms of riboflavin status (265). Animal-source foodsAnimal-source foods: Increased consumption of animal-source foods in a poor population did not result in improved riboflavin status (266). Calcium-enriched foodsCalcium-enriched foods: In human research, increasing food-derived calcium to 1,500mg daily also resulted in an increase in riboflavin intake (267). Carbohydrate-enriched dietCarbohydrate-enriched diet: A high-carbohydrate diet is adequate for riboflavin (268; 269). Low fat intakesLow fat intakes: In epidemiological research and review, low fat intake was related to lower riboflavin intakes (270; 271). MilkMilk: Consumption of milk increased riboflavin intake and levels (272; 273; 274; 275). SpinachSpinach: Consumption of spinach increased riboflavin levels (272). Vegetarian dietVegetarian diet: In human research, riboflavin deficiency occurred in approximately equal numbers of omnivores and lacto-ovo vegetarians, and in greater numbers of vegans (276; 277; 278; 279; 280). Dietary suggestions for vegan children have been made to prevent riboflavin deficiency (281). Truesdell has published a food composition table appropriate for vegetarians to help increase the status of various nutrients, including riboflavin (282). WeanimixWeanimix: Feeding of the weaning food weanimix lacked an effect on riboflavin status in Ghana (283). WineWine: In Italy, wine is considered an important source of riboflavin (284). In a review, brewed alcoholic beverages are indicated to contain nutritionally significant levels of riboflavin (285). YogurtYogurt: In human research, the plasma concentration of flavin adenine dinucleotide (FAD) decreased significantly after consuming probiotics or yogurt, and plasma concentrations of flavin mononucleotide (FMN) and free riboflavin increased (262). Yogurt supplementation of Chinese school children increased riboflavin intake (286). Riboflavin/Lab Interactions:
7-Alpha-hydroxyriboflavin7-Alpha-hydroxyriboflavin: In healthy humans and female patients with liver cirrhosis, oral riboflavin supplementation resulted in the production of 7 alpha-hydroxyriboflavin (7-hydroxymethylriboflavin) in blood plasma (287). Bone mineral densityBone mineral density: In epidemiological research, enhanced riboflavin intake was correlated with increased bone mineral density in individuals with the TT genotype (homozygous mutant) of the methylenetetrahydrofolate reductase (MTHFR) gene (222; 111). Cancer markersCancer markers: In vitro, riboflavin resulted in a reduction in the prevalence of micronuclei in esophageal cells (210). In human research, a treatment plan containing riboflavin, coenzyme Q10, and niacin resulted in a decrease in breast cancer tumor markers and in angiogenesis markers and cytokines (58; 211; 212; 213). CytokinesCytokines: In human research, a treatment plan containing riboflavin, coenzyme Q10, and niacin resulted in a decrease in cytokines (213). DNA methylation patternsDNA methylation patterns: In human research, a treatment plan containing riboflavin, coenzyme Q10, and niacin resulted in a disappearance of RASSF1A DNA methylation patterns (212). Erythrocyte glutathione reductaseErythrocyte glutathione reductase: In human research, riboflavin supplementation resulted in a decrease in the mean activation coefficient of erythrocyte glutathione reductase (184; 288; 289). Flavin mononucleotide and dinucleotideFlavin mononucleotide and dinucleotide: In the elderly, riboflavin supplementation resulted in increases in plasma and erythrocyte flavin mononucleotide and erythrocyte FAD (289). HbA1cHbA1c: In human research, dietary intake of riboflavin may be associated with altered levels of HbA1c (290). HemoglobinHemoglobin: Addition of riboflavin improved the effect of iron and folate with respect to hemoglobin levels (240). In human research, riboflavin therapy improved efficiency of iron utilization (241). HomocysteineHomocysteine: In epidemiological research, enhanced riboflavin status resulted in homocysteine lowering in individuals with the TT genotype (homozygous mutant) of the MTHFR gene (223; 157; 224), and lower riboflavin status was associated with increased plasma homocysteine (225; 226). Riboflavin supplementation may or may not result in homocysteine lowering (291). According to a review, riboflavin is a determinant of plasma homocysteine levels in uremia (292). Inflammatory moleculesInflammatory molecules: A combined supplement of riboflavin, folate, and vitamin B6 resulted in a decrease in intercellular cell adhesion molecules and E-selectin, and increased vascular cell adhesion molecules (293). Insulin-like growth factorInsulin-like growth factor: In human epidemiological research, serum levels of insulin-like growth factor-I (IGF-I) were related to riboflavin intake (294). Medication complianceMedication compliance: Ultraviolet light detection of riboflavin in the urine was a useful marker for medication compliance when riboflavin was included in the medication (23; 25; 295; 33; 34). MTHFR activityMTHFR activity: In human research, addition of riboflavin to folate supplementation resulted in a further increase in MTHFR activity (253). Papillary thresholdPapillary threshold: Iron and riboflavin improved the papillary threshold in vitamin A-supplemented pregnant women in Nepal (239). Platelet storagePlatelet storage: According to platelet studies ex vivo, riboflavin and ultraviolet light resulted in an increase in lactate production and glucose consumption (296); pH was maintained. Pyridoxamine phosphate:oxygen oxidoreductase ratioPyridoxamine phosphate:oxygen oxidoreductase ratio: In human research, riboflavin supplementation in riboflavin-deficient women resulted in a marked increase in the activity of pyridoxamine phosphate:oxygen oxidoreductase (deaminating) (258). RiboflavinRiboflavin: Riboflavin levels increased in the blood following supplementation with a multivitamin and mineral supplement or with riboflavin alone (288; 297; 289; 170; 298; 299; 300). A multivitamin lacked an effect on riboflavin status in human research (301). ZincZinc: In epidemiological research, there was a significant association of percent change in plasma zinc with intake of riboflavin (263).