Iron
Also known as: Ferrous Sulfate, Ferrous Gluconate, Iron Bisglycinate, Fe
Iron is an essential mineral that your body needs to make hemoglobin, the protein in red blood cells that carries oxygen from your lungs to all parts of your body. It also plays roles in energy production, immune function, and cognitive development. Iron deficiency is the most common nutritional deficiency worldwide.
Benefits
Essential for oxygen transport in the blood via hemoglobin. Supports energy production and reduces fatigue associated with anemia. Critical for cognitive development and function, especially in children. Supports immune system function. Necessary for DNA synthesis and cell division. Important during pregnancy — demand increases significantly to support fetal development and increased blood volume.
Recommended Dosage
RDA: Men 8 mg/day, premenopausal women 18 mg/day, pregnant women 27 mg/day, postmenopausal women 8 mg/day. Iron deficiency treatment: 100–200 mg elemental iron daily in divided doses. Upper limit: 45 mg/day elemental iron (from supplements) for adults. Take on empty stomach for best absorption or with vitamin C. Take with food if stomach upset occurs (reduced absorption but better tolerance).
Food Sources
Heme iron (best absorbed): Red meat, poultry, fish, shellfish (especially oysters and clams), organ meats (liver). Non-heme iron: Fortified cereals, beans, lentils, spinach, tofu, dark chocolate, quinoa, chickpeas. Pair non-heme iron with vitamin C foods to enhance absorption.
Side Effects
Common: Constipation, nausea, stomach pain, dark stools (harmless), metallic taste. Taking on an empty stomach maximizes absorption but worsens GI side effects. Iron bisglycinate and carbonyl iron forms may cause fewer side effects. Excessive iron intake: Iron overload can damage organs including the liver, heart, and pancreas.
Interactions
Antacids, calcium, and dairy products reduce iron absorption — separate by 2 hours. Tea, coffee, and high-fiber foods reduce non-heme iron absorption. Vitamin C enhances iron absorption — take together. Tetracycline and fluoroquinolone antibiotics — mutual absorption reduction, separate by 2 hours. Thyroid medications (levothyroxine) — iron reduces absorption, separate by 4 hours.
Warnings
Iron overload (hemochromatosis) is a genetic condition where the body absorbs too much iron — do not supplement without testing iron levels first. Iron supplements are a leading cause of poisoning deaths in children under 6 — keep out of reach. Do not take iron supplements unless deficiency is confirmed by blood work. Men and postmenopausal women rarely need supplementation.
Deficiency Symptoms
Fatigue and weakness (most common), pale skin and nail beds, shortness of breath during normal activity, dizziness and lightheadedness, cold hands and feet, brittle nails (may become spoon-shaped), unusual cravings for ice, dirt, or starch (pica), frequent infections, restless legs syndrome, headache.
Frequently Asked Questions
What are the benefits of Iron?▼
Essential for oxygen transport in the blood via hemoglobin. Supports energy production and reduces fatigue associated with anemia. Critical for cognitive development and function, especially in children. Supports immune system function. Necessary for DNA synthesis and cell division. Important during pregnancy — demand increases significantly to support fetal development and increased blood volume.
What is the recommended dosage for Iron?▼
RDA: Men 8 mg/day, premenopausal women 18 mg/day, pregnant women 27 mg/day, postmenopausal women 8 mg/day. Iron deficiency treatment: 100–200 mg elemental iron daily in divided doses. Upper limit: 45 mg/day elemental iron (from supplements) for adults. Take on empty stomach for best absorption or with vitamin C. Take with food if stomach upset occurs (reduced absorption but better tolerance).
What foods contain Iron?▼
Heme iron (best absorbed): Red meat, poultry, fish, shellfish (especially oysters and clams), organ meats (liver). Non-heme iron: Fortified cereals, beans, lentils, spinach, tofu, dark chocolate, quinoa, chickpeas. Pair non-heme iron with vitamin C foods to enhance absorption.
What are the side effects of Iron?▼
Common: Constipation, nausea, stomach pain, dark stools (harmless), metallic taste. Taking on an empty stomach maximizes absorption but worsens GI side effects. Iron bisglycinate and carbonyl iron forms may cause fewer side effects. Excessive iron intake: Iron overload can damage organs including the liver, heart, and pancreas.
What are the symptoms of Iron deficiency?▼
Fatigue and weakness (most common), pale skin and nail beds, shortness of breath during normal activity, dizziness and lightheadedness, cold hands and feet, brittle nails (may become spoon-shaped), unusual cravings for ice, dirt, or starch (pica), frequent infections, restless legs syndrome, headache.
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Vitamin D is a fat-soluble vitamin that plays a crucial role in calcium absorption, bone health, immune function, and mood regulation. Unlike most vitamins, your body can produce vitamin D when your skin is exposed to sunlight, earning it the nickname 'the sunshine vitamin.'
Vitamin C
Vitamins
Vitamin C is a water-soluble vitamin and powerful antioxidant that the human body cannot produce on its own. It is essential for the growth, development, and repair of all body tissues and plays a role in many body functions including immune defense, collagen formation, and iron absorption.
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Supplement Disclaimer
This supplement information is for educational purposes only and should not replace professional medical advice. Dietary supplements are not intended to diagnose, treat, cure, or prevent any disease. Always consult with a healthcare provider before starting any supplement, especially if you are pregnant, nursing, taking medications, or have a medical condition.