# item.guide
Side-by-Side Comparison Essential Vitamins & Minerals

Iron (Heme & Non-Heme) vs. Vitamin B9 (Folate & Folic Acid)

Comparing 2 standards across 9 specifications. 9 key differences identified.

Comparing:
Iron (Heme & Non-Heme)
Vitamin B9 (Folate & Folic Acid)
Iron (Heme & Non-Heme) →

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.

View full Iron (Heme & Non-Heme) spec sheet →
Vitamin B9 (Folate & Folic Acid) →

Vitamin B9 comprises natural dietary folates (polyglutamates) and synthetic folic acid (monoglutamate). Adult RDA is 400 µg DFE, with a Tolerable Upper Limit of 1,000 µg/day synthetic folic acid, essential as a single-carbon donor in thymidylate DNA synthesis and neural tube closure.

View full Vitamin B9 (Folate & Folic Acid) spec sheet →

Specification Comparison Table

9 Parameters
Parameter / Spec
Iron (Heme & Non-Heme)
Vitamin B9 (Folate & Folic Acid)
Nutrient Type
Essential Trace Mineral Water-Soluble Pteroylglutamate Vitamin
Adult RDA / RDI
8 mg (Men) / 18 mg (Women 19–50) / 27 mg (Pregnancy) 400 µg DFE / day (600 µg DFE pregnancy / prevents neural tube defects)
Tolerable Upper Limit (UL)
45 mg / day (Hemochromatosis / Fenton reaction oxidative stress) 1,000 µg / day (Synthetic folic acid only; masks B12 deficiency neuropathy)
Chemical Forms
Heme Iron (Fe2+ Porphyrin - Animal), Non-Heme Iron (Fe3+ Ferric / Fe2+ Ferrous - Plants/Supplements) (6S)-5-Methyltetrahydrofolate (5-MTHF, active circulating form), Tetrahydrofolate (THF), Folic Acid (Pteroylmonoglutamic acid, synthetic)
Primary Biological Function
Hemoglobin O2 transport, Myoglobin O2 storage, Cytochrome c electron transport, Catalase 1-Carbon transfer reactions, dUMP -> dTMP methylation (Thymidine DNA synthesis), Methionine-Homocysteine cycle, Erythropoiesis
Deficiency Condition
Microcytic Hypochromic Anemia, Severe fatigue, Restless legs syndrome, Pica Neural Tube Defects (Spina bifida, anencephaly in fetuses), Megaloblastic Macrocytic Anemia, Elevated Homocysteine
Top Whole Food Sources
Beef Liver, Oysters, Duck Breast, Beef Ribeye, Lentils, Spinach, Dark Chocolate Beef Liver, Spinach, Asparagus, Brussels Sprouts, Roman Lentils, Chickpeas, Fortified Flours
Bioavailability Difference
Heme: 15–35% absorption (uninhibited); Non-Heme: 2–20% (inhibited by phytates/calcium, boosted by Vitamin C) —
MTHFR Genetic Polymorphism
— Homozygous MTHFR C677T variant reduces folate reduction activity by ~70%, benefiting from direct 5-MTHF supplementation

Other Alternatives to Compare

Compare Iron (Heme & Non-Heme) vs. Calcium (Elemental Ca) → Compare Iron (Heme & Non-Heme) vs. Iodine (Elemental I) → Compare Iron (Heme & Non-Heme) vs. Magnesium (Elemental Mg) → Compare Iron (Heme & Non-Heme) vs. Potassium (Elemental K) → Compare Iron (Heme & Non-Heme) vs. Selenium (Elemental Se) → Compare Iron (Heme & Non-Heme) vs. Sodium (Elemental Na) → Compare Iron (Heme & Non-Heme) vs. Vitamin A (Retinol & Beta-Carotene) → Compare Iron (Heme & Non-Heme) vs. Vitamin B1 (Thiamine) → Compare Iron (Heme & Non-Heme) vs. Vitamin B12 (Cobalamin) → Compare Iron (Heme & Non-Heme) vs. Vitamin B2 (Riboflavin) → Compare Iron (Heme & Non-Heme) vs. Vitamin B3 (Niacin / Nicotinic Acid & Nicotinamide) → Compare Iron (Heme & Non-Heme) vs. Vitamin B5 (Pantothenic Acid) → Compare Iron (Heme & Non-Heme) vs. Vitamin B6 (Pyridoxal 5'-Phosphate / PLP) → Compare Iron (Heme & Non-Heme) vs. Vitamin B7 (Biotin / Vitamin H) → Compare Iron (Heme & Non-Heme) vs. Vitamin C (L-Ascorbic Acid) → Compare Iron (Heme & Non-Heme) vs. Vitamin D3 (Cholecalciferol) → Compare Iron (Heme & Non-Heme) vs. Vitamin E (d-Alpha-Tocopherol) → Compare Iron (Heme & Non-Heme) vs. Vitamin K1 (Phylloquinone) → Compare Iron (Heme & Non-Heme) vs. Zinc (Elemental Zn) →