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Home /Ingredients /Iron

Iron

Also known as: ferrous sulfate, ferrous gluconate, ferrous fumarate, ferric, iron bisglycinate

Essential mineral for oxygen transport in blood (hemoglobin) and energy production. Iron deficiency is the most common nutritional deficiency worldwide.

18mgRDARecommended Dietary Allowance — the daily intake sufficient for 97-98% of healthy adults. Set by the National Institutes of Health.

45mgUpper LimitTolerable Upper Intake Level (UL) — the maximum daily dose unlikely to cause adverse health effects. Exceeding this consistently may increase toxicity risk.

100ProductsNumber of supplements in our database that contain this ingredient.

2Health ClaimsNumber of researched health benefits associated with this ingredient, rated by evidence strength (strong/moderate/weak).

5Side EffectsNumber of documented side effects from clinical literature and adverse event reports.

Health Claims & Evidence

strongSupports iron levels

Iron supplementation is used to address iron deficiency. Should be taken under medical supervision as excess iron can be harmful.

5,783 studies on PubMed

Related studies:Automatically retrieved from PubMed based on keyword matching. Some may not directly address the specific claim above.Iron deficiency anaemia: pathophysiology, assessment, practical management.BMJ Open Gastroenterol (2022) · PMID 34996762 Iron metabolism and iron deficiency anemia in women.Fertil Steril (2022) · PMID 36075747 Iron Deficiency Anemia.Med Clin North Am (2017) · PMID 28189173

strongSupports energy levels

Iron is essential for oxygen transport and cellular energy production.

469 studies on PubMed

Related studies:Automatically retrieved from PubMed based on keyword matching. Some may not directly address the specific claim above.The Influence of Nutritional Intervention in the Treatment of Hashimoto's Thyroiditis-A Systematic Review.Nutrients (2023) · PMID 36839399 Main nutritional deficiencies.J Prev Med Hyg (2022) · PMID 36479498 Vitamins and Minerals for Energy, Fatigue and Cognition: A Narrative Review of the Biochemical and Clinical Evidence.Nutrients (2020) · PMID 31963141

Known Side Effects

constipation
nausea
stomach pain
dark stools
toxicity in overdose (especially children)

Drug Interactions

antacids
calcium supplements
tetracycline antibiotics
levodopa
levothyroxine

Always consult your healthcare provider before combining supplements with medications.

Products Containing Iron (100)

Coast ScienceFertile One Prenatal Plus

KagedMultivitamin

QualitestTri-Vit With Fluoride 0.25 mg and Iron Drops

Healthy For LifeMineral Supplement

Pink StorkFertility

Everyday HealthNZ-Fe Fort

Country Life Realfood OrganicsPrenatal

Coast ScienceGeneration M

ShakleeLiqui-Lea Natural Fruit Flavor

FloraFlora Iron

Nature's GiftsMother Kare Prenatal Multivitamin

Carwin Pharmaceutical AssociatesQuFlora FE Grape Flavor

Advanced Nutrition by ZahlerMighty Mini

Dr. WholenessBlood Vitality

QualitestMulti-Vit With Fluoride 0.25 mg And Iron Drops

Zarbee's Naturals BabyMultivitamin with Iron Supplement Natural Grape Flavor

Healthy For LifeNatural Mineral Supplement

Coast Science She-ologyPMS Plus

Rainbow LightComplete Iron Mini-Tabs

Rexall Sundown NaturalistOne Daily Energy

Recommended Intake

RDA (adults)Recommended Dietary Allowance — daily intake sufficient for 97-98% of healthy adults.18 mg

Upper LimitTolerable Upper Intake Level — maximum daily dose unlikely to cause adverse effects.45 mg

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Iron — Benefits, Dosage, Side Effects & Top Products | The Supplement Ratings