Iron (Heme & Non-Heme) vs. Vitamin B2 (Riboflavin)
Comparing 2 standards across 9 specifications. 9 key differences identified.
Iron is an essential redox trace element central to hemoglobin oxygen transport, myoglobin storage, and mitochondrial electron transport chain cytochromes. Adult RDA is 8mg (men/post-menopausal women) / 18mg (pre-menopausal women), with a Tolerable Upper Limit of 45mg/day.
Vitamin B2 is an essential water-soluble isoalloxazine vitamin serving as the core structural component of Flavin Mononucleotide (FMN) and Flavin Adenine Dinucleotide (FAD) coenzymes in cellular redox respiration. Adult RDA is 1.3 mg (men) / 1.1 mg (women).
Specification Comparison Table
9 Parameters| Parameter / Spec | ||
|---|---|---|
|
Nutrient Type
|
Essential Trace Mineral | Water-Soluble Isoalloxazine Vitamin |
|
Adult RDA / RDI
|
8 mg (Men) / 18 mg (Women 19–50) / 27 mg (Pregnancy) | 1.3 mg / day (Men) / 1.1 mg / day (Women) |
|
Tolerable Upper Limit (UL)
|
45 mg / day (Hemochromatosis / Fenton reaction oxidative stress) | None Established (Saturates intestinal absorption at ~27mg; excreted as harmless bright yellow urine) |
|
Chemical Forms
|
Heme Iron (Fe2+ Porphyrin - Animal), Non-Heme Iron (Fe3+ Ferric / Fe2+ Ferrous - Plants/Supplements) | Riboflavin, Riboflavin-5'-Phosphate (FMN), Flavin Adenine Dinucleotide (FAD) |
|
Primary Biological Function
|
Hemoglobin O2 transport, Myoglobin O2 storage, Cytochrome c electron transport, Catalase | Complex I and Complex II mitochondrial electron transport chain cytochromes, Glutathione Reductase, B6/Folate activation |
|
Deficiency Condition
|
Microcytic Hypochromic Anemia, Severe fatigue, Restless legs syndrome, Pica | Ariboflavinosis (Angular cheilitis / cracked lip corners, glossitis / magenta tongue, seborrheic dermatitis) |
|
Top Whole Food Sources
|
Beef Liver, Oysters, Duck Breast, Beef Ribeye, Lentils, Spinach, Dark Chocolate | Beef Liver, Dairy Milk, Greek Yogurt, Eggs, Almonds, Portobello Mushrooms, Spinach |
|
Bioavailability Difference
|
Heme: 15–35% absorption (uninhibited); Non-Heme: 2–20% (inhibited by phytates/calcium, boosted by Vitamin C) | — |
|
Photodegradation Vulnerability
|
— | Extremely light-sensitive (dairy milk stored in clear glass loses 50% riboflavin within 2 hours of sunlight exposure) |