Iron | Supplementopedia

Overview

Iron is a vital mineral crucial for hemoglobin production. Hemoglobin, a protein in red blood cells, carries oxygen to body tissues.
Its primary function is maintaining healthy red blood cells and preventing iron-deficiency anemia (characterized by fatigue, weakness, and shortness of breath).
Iron supplementation ensures adequate oxygen delivery to cells, supporting energy and well-being.

Benefits

Cognitive Function: Iron is necessary for hemoglobin production, which carries oxygen to the brain, supporting cognitive function, attention, and memory (1).
Energy Production: A critical component of enzymes in energy production (citric acid cycle and electron transport chain), supporting physical performance and reducing fatigue (2).
Physical Performance: Iron deficiency impairs oxygen delivery to muscles, decreasing physical performance. Adequate iron supports endurance, strength, and exercise performance (3).
Immune System: Essential for immune cell function (T-cells and macrophages), aiding in fighting infections and diseases (4).
Metabolic Health: Involved in glucose metabolism regulation; deficiency is linked to increased type 2 diabetes risk (5).
Cardiovascular Health: Helps regulate blood pressure and supports blood vessel health, reducing cardiovascular disease risk (6).
Neurological Health: Necessary for neurotransmitter synthesis (dopamine and serotonin), regulating mood, motivation, and other neurological functions (7).
Pregnancy and Fetal Development: Essential for fetal growth and development during pregnancy; deficiency increases preterm labor and low birth weight risk (8).
Menstrual Health: Regulates menstrual cycles and reduces iron deficiency anemia risk, common in women of childbearing age (9).
Exercise-Induced Oxidative Stress: Possesses antioxidant properties, protecting against exercise-induced oxidative stress and muscle damage (10).

References:

Bruner et al. (2018). Iron deficiency and cognitive performance in children and adolescents. Journal of Pediatric Health Care, 32(3), 251-258.
Hurrell et al. (2010). Iron bioavailability and dietary reference values. The American Journal of Clinical Nutrition, 91(5), 1461S-1467S.
Peeling et al. (Note: Reference 3 is incomplete in the original text)

How It Works

Iron facilitates oxygen and electron transport, vital for energy production, DNA synthesis, and cellular processes.
Mechanism of Action: Exists in ferrous (Fe2+) and ferric (Fe3+) states, participating in redox reactions (donating or accepting electrons). Iron-containing proteins (hemoglobin, myoglobin, cytochromes) utilize this property for biological functions.
Pathways Affected:
- Oxygen Transport: Hemoglobin (iron-containing) binds oxygen in the lungs and releases it to tissues.
- Electron Transport Chain: Cytochromes (iron-containing) are central to ATP (energy) generation in mitochondria.
- DNA Synthesis: A cofactor for ribonucleotide reductase (converts ribonucleotides to deoxyribonucleotides).
- Antioxidant Defense: Component of enzymes like catalase and peroxidase, protecting cells from oxidative damage.
Produces its Effects Through:
- Binding to proteins (transferrin for transport, ferritin for storage).
- Redox reactions (electron transfer for energy production and cellular processes).
- Enzyme activation (cofactor for aconitase and succinate dehydrogenase in the citric acid cycle and electron transport chain).
- Gene regulation (influences gene expression by binding to transcription factors like iron-regulatory protein (IRP)).

Dosage

Standard Dosage Ranges:

Adults: 30-100 mg/day, divided into 2-3 doses.
Pregnant women: 30-60 mg/day, divided into 2-3 doses.
Children (3-12 years): 3-6 mg/day, divided into 2-3 doses.
Children (1-2 years): 1-3 mg/day, divided into 2-3 doses.
Infants: 0.5-1 mg/day, divided into 2-3 doses.

Timing Recommendations:

Take on an empty stomach (1 hour before or 2 hours after meals) for maximized absorption.
Avoid taking with milk, calcium, or antacids (inhibit absorption).
Consider bedtime administration to reduce nausea and stomach upset.

Special Considerations:

Pregnancy and lactation: 30-60 mg/day is recommended.
Iron deficiency anemia: Higher doses (100-200 mg/day) may be necessary under medical supervision.
Gastrointestinal issues: Higher doses or alternative forms (intravenous iron) may be required.
Kidney disease: Lower doses or alternative forms are necessary to avoid exacerbating kidney damage.
Hemochromatosis: Avoid iron supplements altogether.

Forms of Iron:

Ferrous sulfate (various strengths, e.g., 65 mg, 100 mg).
Ferrous gluconate (gentler, for sensitive stomachs).
Ferrous fumarate (highly bioavailable).

Monitoring and Adjustments: (Note: This section is incomplete in the original text)

Safety & Side Effects

Known Side Effects:

Gastrointestinal symptoms: nausea, vomiting, diarrhea, constipation, abdominal pain, cramping.
Dark or black tarry stools (due to unabsorbed iron).
Metallic taste.
Headache.
Dizziness or lightheadedness.
Fatigue or weakness.
Allergic reactions (rare): hives, itching, swelling, difficulty breathing.

Contraindications:

Hemochromatosis (excessive iron absorption).
Hemolytic anemia (rapid red blood cell destruction).
Iron overload or toxicity.
Active peptic ulcer or gastrointestinal bleeding.

Drug Interactions:

Antacids (decrease absorption).
Biphosphonates (e.g., alendronate) (decrease absorption).
Calcium supplements (decrease absorption).
Levodopa, methyldopa, penicillamine, quinolone antibiotics, tetracycline antibiotics, thyroid hormones (iron may decrease their effectiveness).

Safety Considerations:

Accidental overdose is toxic, especially in children. Keep out of reach of children.
Pregnancy and breastfeeding: Generally safe, but high doses may cause adverse effects. Consult a healthcare provider.
Pediatric use: Not recommended for children under 6 unless advised by a healthcare provider.
Geriatric use: Older adults may be more susceptible to toxicity due to decreased renal function.

Populations Who Should Avoid or Use with Caution:

Pregnant women with multiple gestations (high doses may increase preterm labor risk).
Breastfeeding women with hemochromatosis (may worsen the condition).

Chemistry

Iron (Fe), atomic number 26, is a first transition series metal.
Chemical Structure: Atomic number: 26; Atomic mass: 55.847(3) u; Electron configuration: [Ar] 3d6 4s2.
IUPAC Name: Iron (Latin: ferrum).
Key Structural Features:
- Crystal structure: Body-centered cubic (BCC) at room temperature, transforming to face-centered cubic (FCC) above 912°C.
- Atomic radius: ~124 pm.
- Electronegativity: 1.83 (Pauling scale).
- Oxidation states: +2, +3, +4, +5, +6.
Properties:
- Physical: Silver-gray metal; melting point 1538°C; boiling point 2862°C; highly ductile.
- Chemical: Highly reactive; forms compounds with oxygen, carbon, and sulfur; susceptible to corrosion.
- Magnetic: Ferromagnetic (Note: The original text cuts off here)

Sources & Quality

Natural Sources:

Dietary Sources: Red meat, poultry, fish, legumes, nuts and seeds, whole grains, leafy greens.
Earth's Crust: Iron ore deposits (hematite (Fe2O3), magnetite (Fe3O4), siderite (FeCO3)), iron-rich soil and rocks.

Extraction/Synthesis Methods:

Mining and Smelting: Iron ore extraction and smelting to produce pure iron.
Refining: Processes like electrolysis for high-purity iron.
Synthetic Production: Chemical reactions (e.g., iron oxide reduction with hydrogen or carbon).
Ferrous Sulfate Production: Reaction of iron with sulfuric acid.

Supplement Forms and Quality Considerations:

Ferrous sulfate (commonly used, well-tolerated, effective).
Ferrous gluconate (for sensitive stomachs).
Iron citrate (highly bioavailable).
Heme iron (from animal sources, easily absorbed).
Quality Considerations: (Note: This section is incomplete in the original text)