The Claim

Iron bioaccessibility from dietary supplements and medicinal products varies significantly based on the chemical form of iron, with iron sulfate demonstrating the highest bioaccessibility (12.58%) compared to iron lactate (5.25%), iron fumarate (6.03%), and iron bisglycinate (7.32%) under simulated gastrointestinal conditions.

Source: Influence of Diet on Bioaccessibility of Iron from Dietary Supplements and Medicinal Products—Results of In Vitro Digestion Model and Analytical Determinations

What the research says

Supports is higher

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Supports
8score
Challenges
0score

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Quantitative
1 study reviewed
In plain English

Different chemical forms of iron in supplements release different amounts of iron when tested under conditions mimicking the human digestive tract, with iron sulfate releasing the most and iron lactate releasing the least.

See the scientific wording

Iron bioaccessibility from dietary supplements and medicinal products varies significantly based on the chemical form of iron, with iron sulfate demonstrating the highest bioaccessibility (12.58%) compared to iron lactate (5.25%), iron fumarate (6.03%), and iron bisglycinate (7.32%) under simulated gastrointestinal conditions, indicating that chemical speciation strongly influences the amount of iron released for potential absorption.

Why this might work

Iron in the form of sulfate dissolves quickly in stomach acid, releasing iron ions that stay soluble and ready for absorption in the small intestine. Other forms like lactate, fumarate, and bisglycinate dissolve more slowly or form stable complexes that resist breaking apart, so less iron becomes available for the body to use. Vitamin C helps keep iron in its absorbable form, while calcium and plant compounds bind to iron and stop it from being absorbed.

Verified mechanismbased on 1 study

What the research says

1 study

  1. Study: Influence of Diet on Bioaccessibility of Iron from Dietary Supplements and Medicinal Products—Results of In Vitro Digestion Model and Analytical Determinations

    Scientists tested different kinds of iron pills in a lab that mimics human digestion and found that iron sulfate releases the most iron, while other forms like iron lactate release much less — meaning your body might absorb more from sulfate pills.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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