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Iron

  • Nutrient
  • Varies by country
  • Identity checked
  • Sources last checked 2026-09-04

This page shows what was measured, who it was measured in, and what that does not settle.

What Iron does in the body

Use immediatelyafter package is opened.

Why people take it. Directions Take Heating Patch out ofpackaging.Use immediatelyafter package is opened.

What happened in people

RNAWiki has not yet published a reviewed conclusion for this use.

A fixed RNAWiki sentence

Where this came from

Wording RNAWiki always uses, not a finding about this substance.

No reviewed claim names a result for any goal on this record.

No source is stored against this line.

The limit that matters most

Not recorded.

Where it acts
Not recorded.
Kind of result
No result is published, so no kind of result applies yet
Supervision
Not usually supervised: sold as a supplement or food ingredient where recorded. That is a legal category, not a safety judgement.

What the registries record it as

  • The substance registry classes this as chemical.

    FDA substance registry · E1UOL152H7 · read 2026-08-29

  • The supplement label database classes it as mineral, under the name Iron.

    NIH Dietary Supplement Label Database · 254 · read 2026-08-29

Where each sentence above came from

The use the label states, quoted from it. No plain-language version of this sentence has been written.

The use the label states, quoted from it. It is written for a clinician, not for a reader without medical training.

No statement of the main limit is recorded.

The four opening statements run to 29 words.

Words this page uses

Four words worth knowing first

Chosen from what this page shows, with each one explained before the word it depends on.

Stand-in result

A stand-in result is a number measured because the real result takes too long.

A picture of it, and where the picture fails

It is like judging a journey by the speedometer rather than by arriving.

Where that stops being true. Speed does predict arrival. Many stand-in results do not predict the real one.

What people get wrong. A stand-in result is often reported as the result itself.

A surrogate endpoint substituted for a clinical endpoint, valid only where the substitution has been shown to hold.

Enzyme

An enzyme is a protein that speeds up one chemical change.

A picture of it, and where the picture fails

An enzyme is like a machine on a production line doing one cut.

Where that stops being true. A machine is switched on and off by a person. Enzymes are controlled by the cell.

What people get wrong. Enzymes are thought to be used up. They are not; they work again and again.

A catalytic protein that lowers the activation energy of a specific reaction.

Receptor

A receptor is a part of a cell that a signal fits into.

A picture of it, and where the picture fails

A receptor is like a lock waiting for one key.

Where that stops being true. A lock either opens or does not. A receptor can be half-triggered, or worn out.

What people get wrong. Fitting a receptor is read as causing a benefit. It causes a step, and nothing more.

A protein that binds a specific ligand and converts that binding into a cellular response.

Pathway

A pathway is a chain of steps inside a cell, each one setting off the next.

A picture of it, and where the picture fails

A pathway is like a row of dominoes.

Where that stops being true. Dominoes fall one way. Pathways loop back and can switch themselves off.

What people get wrong. Changing one step is read as changing the outcome. Other steps often absorb it.

An ordered series of molecular interactions producing a defined cellular change.

What happened in peopleRead from sources, not yet reviewed

What was measured, goal by goal

One row for each goal a registered study measured something for. One column for each kind of thing that could be measured.

Registered studies list 40 outcome measures that RNAWiki could read. A registered study says what someone planned to measure. It does not say what they found. 0 of the matched studies tested this substance, and 0 posted a result.

There is no single score. A strong test result and a weak life result are different facts.

Goals down the side, kinds of measurement across the top. Each cell says what kind of thing was registered, not what was found.
GoalLife outcomeWhat a body can doHow a person feelsA test resultA step in the bodyHarmsHow longWho was studied
PainNothing in the sources checkedNo registered study lists a life outcome for this goal.Nothing in the sources checkedNo registered study lists a performance measure for this goal.Waiting for a reviewer2 registered symptom measure.Nothing in the sources checkedNo registered study lists a test result for this goal.Nothing in the sources checkedNo registered study lists a body-step measure for this goal.Not recordedHarms were not a registered measure for this goal.Not recordedNo finished study window is recorded.Waiting for a reviewerWho was studied is listed further down the page.
StrengthNothing in the sources checkedNo registered study lists a life outcome for this goal.Waiting for a reviewer1 registered performance measure of this kind.Nothing in the sources checkedNo registered study lists a symptom measure for this goal.Nothing in the sources checkedNo registered study lists a test result for this goal.Nothing in the sources checkedNo registered study lists a body-step measure for this goal.Not recordedHarms were not a registered measure for this goal.Not recordedNo finished study window is recorded.Waiting for a reviewerWho was studied is listed further down the page.
Blood sugarNothing in the sources checkedNo registered study lists a life outcome for this goal.Nothing in the sources checkedNo registered study lists a performance measure for this goal.Nothing in the sources checkedNo registered study lists a symptom measure for this goal.Only a number moved1 registered test measure.Nothing in the sources checkedNo registered study lists a body-step measure for this goal.Not recordedHarms were not a registered measure for this goal.Not recordedNo finished study window is recorded.Waiting for a reviewerWho was studied is listed further down the page.
EnergyNothing in the sources checkedNo registered study lists a life outcome for this goal.Nothing in the sources checkedNo registered study lists a performance measure for this goal.Waiting for a reviewer1 registered symptom measure.Nothing in the sources checkedNo registered study lists a test result for this goal.Nothing in the sources checkedNo registered study lists a body-step measure for this goal.Not recordedHarms were not a registered measure for this goal.Not recordedNo finished study window is recorded.Waiting for a reviewerWho was studied is listed further down the page.
Which registered measures put each goal on this table
Pain
pain; knee pain
Strength
muscle strength
Blood sugar
glucose
Energy
fatigue

Sorted by fixed word lists, version v1. A name the rules do not recognise stays unsorted rather than moving to the nearest column.

What each mark on this table means
Nothing in the sources checked
No registered study lists a life outcome for this goal.
Waiting for a reviewer
2 registered symptom measure.
Not recorded
Harms were not a registered measure for this goal.
Only a number moved
1 registered test measure.

What happened in peopleRead from sources, not yet reviewed

What happened in people

Each card is one study: the exact question it asked, who was in it, and whether it showed what it set out to show.

Baseline to end-line change in the prevalence of stunting among children 0-59 months of age

The study did not show it

Who was studied
NCT06025786
How many people
13200
Study design
Not applicable
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
Repeated elsewhere
Unreplicated

What this does not prove. A study that did not show an effect does not show that no effect exists anywhere.

The limits of this study, and where it came from

Main limit. No limitation is recorded for this study.

How far it carries. This study is recorded from the curated record, not from the registry match.

Form and route. Topical

Interval reported. Not recorded in this summary

Written into the record, not signed off as a reviewed claim.

  • openFDA NDC Directory · a recorded source, not a stored snapshot
  • openFDA SPL label · a recorded source, not a stored snapshot
  • PubChem PUG-REST · a recorded source, not a stored snapshot
  • FDA label (openFDA SPL) · a recorded source, not a stored snapshot

Number of home fortification sachets consumed

The study did not show it

Who was studied
NCT02593136
How many people
11861
Study design
Not applicable
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
Repeated elsewhere
Unreplicated

What this does not prove. A study that did not show an effect does not show that no effect exists anywhere.

The limits of this study, and where it came from

Main limit. No limitation is recorded for this study.

How far it carries. This study is recorded from the curated record, not from the registry match.

Form and route. Topical

Interval reported. Not recorded in this summary

Written into the record, not signed off as a reviewed claim.

  • openFDA NDC Directory · a recorded source, not a stored snapshot
  • openFDA SPL label · a recorded source, not a stored snapshot
  • PubChem PUG-REST · a recorded source, not a stored snapshot
  • FDA label (openFDA SPL) · a recorded source, not a stored snapshot

Exclusive breastfeeding (EBF) among children 0-6 months of age

The study did not show it

Who was studied
NCT01678716
How many people
8800
Study design
Not applicable
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
Repeated elsewhere
Unreplicated

What this does not prove. A study that did not show an effect does not show that no effect exists anywhere.

The limits of this study, and where it came from

Main limit. No limitation is recorded for this study.

How far it carries. This study is recorded from the curated record, not from the registry match.

Form and route. Topical

Interval reported. Not recorded in this summary

Written into the record, not signed off as a reviewed claim.

  • openFDA NDC Directory · a recorded source, not a stored snapshot
  • openFDA SPL label · a recorded source, not a stored snapshot
  • PubChem PUG-REST · a recorded source, not a stored snapshot
  • FDA label (openFDA SPL) · a recorded source, not a stored snapshot

Product sales and use (coverage)

The study did not show it

Who was studied
NCT01088958
How many people
7200
Study design
Phase 4
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
Repeated elsewhere
Unreplicated

What this does not prove. A study that did not show an effect does not show that no effect exists anywhere.

The limits of this study, and where it came from

Main limit. No limitation is recorded for this study.

How far it carries. This study is recorded from the curated record, not from the registry match.

Form and route. Topical

Interval reported. Not recorded in this summary

Written into the record, not signed off as a reviewed claim.

  • openFDA NDC Directory · a recorded source, not a stored snapshot
  • openFDA SPL label · a recorded source, not a stored snapshot
  • PubChem PUG-REST · a recorded source, not a stored snapshot
  • FDA label (openFDA SPL) · a recorded source, not a stored snapshot

Prevalence of low birthweight

The study did not show it

Who was studied
NCT05836961
How many people
5500
Study design
Not applicable
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
Repeated elsewhere
Unreplicated

What this does not prove. A study that did not show an effect does not show that no effect exists anywhere.

The limits of this study, and where it came from

Main limit. No limitation is recorded for this study.

How far it carries. This study is recorded from the curated record, not from the registry match.

Form and route. Topical

Interval reported. Not recorded in this summary

Written into the record, not signed off as a reviewed claim.

  • openFDA NDC Directory · a recorded source, not a stored snapshot
  • openFDA SPL label · a recorded source, not a stored snapshot
  • PubChem PUG-REST · a recorded source, not a stored snapshot
  • FDA label (openFDA SPL) · a recorded source, not a stored snapshot

Stunting in Children at 18 mo

The study did not show it

Who was studied
NCT01562379
How many people
5449
Study design
Phase 2/Phase 3
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
Repeated elsewhere
Unreplicated

What this does not prove. A study that did not show an effect does not show that no effect exists anywhere.

The limits of this study, and where it came from

Main limit. No limitation is recorded for this study.

How far it carries. This study is recorded from the curated record, not from the registry match.

Form and route. Topical

Interval reported. Not recorded in this summary

Written into the record, not signed off as a reviewed claim.

  • openFDA NDC Directory · a recorded source, not a stored snapshot
  • openFDA SPL label · a recorded source, not a stored snapshot
  • PubChem PUG-REST · a recorded source, not a stored snapshot
  • FDA label (openFDA SPL) · a recorded source, not a stored snapshot
What we know
RNAWiki holds 6 written-up human studies for this substance, each with the question it asked.
How we know it
Each card names the study, the number of people and what the study set out to measure.
What this does not prove
These summaries were written by a person and have not been signed off as reviewed claims.
Why it matters
A study that failed is as informative as one that worked, and both are here.
What we still do not know
No reviewed claim exists, so no exact population, effect size or interval is published yet.

What happened in peopleRead from sources, not yet reviewed

How close this is to real life

The top step is something a person would feel or care about. The bottom is a guess from software. Filled steps are where evidence exists for this substance.

  1. Living longer, or avoiding a major event No evidence recorded. Death, a heart attack, a stroke, a hospital stay.No registered study measures this.
  2. What a body can do day to day Evidence recorded. Walking, dressing, breathing, recovering.3 registered measures of this kind.
  3. Measured performance Evidence recorded. How much was lifted, how far was run, how fast.3 registered measures of this kind.
  4. Symptoms and quality of life Evidence recorded. Pain, tiredness, mood, sleep, as the person rated it.5 registered measures of this kind.
  5. A number that stands in for health Evidence recorded. Cholesterol, blood sugar, bone density. A stand-in, not the thing itself.9 registered measures of this kind.
  6. A step measured inside a person Evidence recorded. Something measured in human tissue or human cells.A human record sits on the stored organism ladder.
  7. Animals Evidence recorded. Mice, rats, dogs. Useful for ideas, not proof about people.Stored records in Yeast, C. elegans (roundworm), Drosophila (fruit fly), Mouse, Rat, Dog, Non-human primate. A result in animals says what to test next. It does not say what happens in people.
  8. Cells in a dish Evidence recorded. Cells or chemistry on a bench, far from a whole body.Stored mechanism abstracts describe steps measured in cells or tissue.
  9. A guess from software No evidence recorded. Nobody measured it. RNAWiki never publishes one as a finding.RNAWiki stores no prediction for this record. Software can suggest a link. RNAWiki does not publish one as a finding.

Higher on these steps means closer to something a person would feel. It does not mean better done.

What it would be like to takeRead from sources, not yet reviewed

Felt, measured, or meaningful

Three different things that get called the same word. Registered studies measured all three, and mixing them is how a blood test becomes a health claim.

Felt

Things a person could notice without a test.

  • symptom severity scale
  • pain
  • health related quality of life
  • knee pain
  • fatigue

Measured

Things only a test, a scale or a device shows.

  • decrease in supine systolic blood pressure
  • hemoglobin
  • hemoglobin levels
  • hemoglobin level
  • hemoglobin concentration
  • systolic blood pressure
  • muscle strength
  • glucose
  • serum ferritin
  • heart rate

Meaningful

Things that change how a life goes, not only a number.

  • functional disability
  • functional capacity

A registered study says what someone planned to measure. It does not say what they found. A number moving is not the same as a life going better. The two are shown apart here.

Felt, but not shown to help. A person notices a change. No study showed it leads anywhere good.

Measured, but not felt. A number moves. The person notices nothing. Both can be true.

Measured, but not shown to matter. A number moves in the good direction. Nobody showed that lives went better.

Matters, but takes years. The result that counts may take longer than anyone would keep watching.

Names that fit none of the three (23)
  • incidence of diarrhea
  • whose rebleeds decreased from baseline by 50 at 12 months
  • cessation of bleeding
  • oxidative stress
  • incidence of placental malaria
  • infant birth weight
  • maximum change from baseline in hb during weeks 3 13
  • proportion recovered from moderate acute malnutrition
  • maternal change in mid upper arm circumference
  • infant birth length
  • premature delivery
  • psychomotor development
  • complete blood count
  • glycemic response
  • feasibility of enrolling in the trial
  • fecal calprotectin
  • side effects
  • stride length
  • knee range of motion
  • nrf2 expression

These are harms, study-process measures, or names the rules did not recognise. They are shown rather than dropped.

What is missing or unclearRead from sources, not yet reviewed

Were people like you studied?

RNAWiki cannot tell whether a study fits you. It can show who was in it, and where the result stops carrying.

Who was studied

People similar to this profile were included.

  • Directions Take Heating Patch out ofpackaging.Use immediatelyafter package is opened. Remove paper from theadhesive backing. Place on pain area againsunderwear/clothing, not against skin.

Who is missing from the studies

  • Which groups were under-represented in the studies has not been recorded for this substance. Pregnancy, breastfeeding, children, older adults, and people with liver or kidney conditions are commonly excluded from trials; nothing here says whether they were.

Where the result stopped carrying

  • This is a scope explorer, not a diagnosis engine.
  • It shows who was studied so you can see whether people similar to you were included.

RNAWiki cannot tell whether a study fits you. It can show who was in it.

What it would be like to takeRead from sources, not yet reviewed

Why it might seem to do nothing

A real effect and a noticed effect are different things. These are the recorded reasons the two come apart.

It was studied for a different goal

The studies measured something else entirely.

On this record: Some registered studies measured things that match no goal on this page.

It was studied in different people

The people in the studies were not much like the reader.

On this record: Which groups were under-represented in the studies has not been recorded for this substance. Pregnancy, breastfeeding, children, older adults, and people with liver or kidney conditions are commonly excluded from trials; nothing here says whether they were.

The evidence may simply be wrong

Small early studies often do not hold up.

On this record: RNAWiki has not yet published a reviewed conclusion for this use.

Other reasons RNAWiki checked and found nothing for (10)
A different form was studied
The studied form is not the form on the shelf. Nothing in this record points to this reason.
There was nothing to correct
Where a level is already normal, topping it up may change nothing. Nothing in this record points to this reason.
Something else had to happen too
In the studies it was paired with training, a diet or another treatment. Nothing in this record points to this reason.
The change is too small to feel
A real change can still sit below what a person notices. Nothing in this record points to this reason.
Day-to-day swing hides it
Sleep, food, stress and time of day move most numbers more than this would. Nothing in this record points to this reason.
Not enough time yet
The studies ran longer than the person has waited. Nothing in this record points to this reason.
It was not taken as studied
Missed days change the result, and studies count them. Nothing in this record points to this reason.
Something else changed at the same time
Two changes at once cannot be told apart afterwards. Nothing in this record points to this reason.
The product may not be what it says
Contents of a sold product are not always what the label states. Nothing in this record points to this reason.
No recorded reason
RNAWiki has nothing stored that would explain it. Nothing in this record points to this reason.

None of these is a reason to take more. Taking more is not a step this page ever suggests.

What it would be like to takeRead from sources, not yet reviewed

What taking it involves

The recorded facts about getting hold of it and using it. Nothing here is a suggestion about what you should do.

How it is supplied

Varies by country

Quoted from a source

Where this came from

Copied from a source RNAWiki stored, with the source named.

Read from the recorded approval status.

No source is stored against this line.

Form and route

Topical

Source-linked record

Where this came from

A person wrote this into the record with the study named beside it. No reviewer has signed it off.

The form and route recorded on this substance.

No source is stored against this line.

Who oversees it

Not usually supervised: sold as a supplement or food ingredient where recorded. That is a legal category, not a safety judgement.

Quoted from a source

Where this came from

Copied from a source RNAWiki stored, with the source named.

The identity record classes it as a supplement ingredient; no medicines register records an approval.

No source is stored against this line.

What is in the pack

Sold as patch, given by the topical route.

Source-linked record

Where this came from

A person wrote this into the record with the study named beside it. No reviewer has signed it off.

Recorded notes on how this is sold and what that means for what is in the pack.

No source is stored against this line.

Where it is registered

Regulatory records are listed in the technical disclosure at the foot of this page.

Counted from records

Where this came from

A count of rows RNAWiki holds. It describes our records, not your body.

Register entries are stored per jurisdiction and shown with their dates.

No source is stored against this line.

Why people stop

Not recorded.

Nothing recorded

Where this came from

RNAWiki holds nothing here and says so rather than guessing.

No record of why people stopped taking it is stored for this substance.

No source is stored against this line.

What it would be like to takeNothing found in the sources checked

What can go wrong

Sorted by where each line came from. A regulator's label and a report somebody sent in are not the same kind of fact.

Nothing found in the sources checked

No harm is recorded against this substance in the sources RNAWiki checked. Finding nothing is not the same as showing there is nothing.

The sources listed were searched and held nothing. That is not the same as nothing existing.

Over a long time. No completed tested study window is recorded, so long-term effects are not established by the registry record.

Groups the studies covered thinly. Which groups were under-represented in the studies has not been recorded for this substance. Pregnancy, breastfeeding, children, older adults, and people with liver or kidney conditions are commonly excluded from trials; nothing here says whether they were.

What is missing or unclearRead from sources, not yet reviewed

Does the exact form matter?

Evidence belongs to the exact thing that was tested. A different salt, a different mixture or a different preparation is a different question.

The form that was studied

Topical

Source-linked record

Where this came from

A person wrote this into the record with the study named beside it. No reviewer has signed it off.

The form used in the studies cited on this page.

No source is stored against this line.

What is sold

Not recorded.

Nothing recorded

Where this came from

RNAWiki holds nothing here and says so rather than guessing.

Nothing further is recorded about which forms are sold.

No source is stored against this line.

What is recorded as being sold

  • 1 product lists this as an active ingredient in the United States drug directory. 1 of them contain it and nothing else.

    FDA National Drug Code directory · 73076-179 · read 2026-08-29

  • They are sold as patch, taken topical.

    FDA National Drug Code directory · 73076-179 · read 2026-08-29

  • 1 published label names it as an active ingredient. 1 of them describe this substance alone, which is where its own label text on this page comes from.

    US prescribing information · 31142e15-aab1-5787-e063-6394a90a16d4 · read 2026-08-29

  • Those labels are classed as human otc drug.

    US prescribing information · 31142e15-aab1-5787-e063-6394a90a16d4 · read 2026-08-29

  • 19078 marketed supplement labels list this ingredient, classed as amino acid/protein, botanical, mineral and other combinations.

    NIH Dietary Supplement Label Database · 229239 · read 2026-08-29

  • Those labels carry all other, nutrient and structure/function claims. A claim of that kind is written by the manufacturer and is not assessed by any regulator, so its presence says nothing about whether it is true.

    NIH Dietary Supplement Label Database · 229239 · read 2026-08-29

Evidence carries across two names for one substance. It does not carry across a salt, a mirror form or a mixture.

What it would be like to takeRead from sources, not yet reviewed

What you could measure

Watching one thing carefully can tell you whether it moved. It cannot tell you what moved it.

This is sold without a prescription, so a person can sensibly watch one thing and see whether it moves.

  1. Pick one goal. One goal only. Two at once cannot be told apart afterwards.

  2. Pick one thing to watch. Registered studies measured things like: decrease in supine systolic blood pressure; hemoglobin; hemoglobin levels.

  3. Measure before you start. Take the same measurement several times first. One reading is not a starting point.

  4. Know the swing. Write down how much it moves on its own across a normal week.

  5. Change one thing. Change nothing else at the same time, including training and sleep.

  6. Give it the study length. No finished study window is recorded, so no length is suggested here.

  7. Track whether you took it. Missed days are the most common reason a home test shows nothing.

  8. Read the trend. Look at the line across weeks. A single reading tells you almost nothing.

What not to measure

  • Anything that swings more day to day than the change you are looking for.
  • A wearable estimate of sleep stages, which is an estimate and not a measurement.
  • Weight on one morning, which mostly records water.
  • A feeling you did not write down before starting, such as: symptom severity scale.

When to stop

  • Stop if something new and unpleasant starts, and ask a pharmacist or doctor.
  • Stop if you cannot keep everything else steady, because the result will not mean anything.
  • Stop at the end of the window you set, and read the trend then.

Tracking can show whether something changed for you. It cannot show what caused it.

RNAWiki does not work out an amount for anyone.

What is missing or unclearRead from sources, not yet reviewed

What nobody knows yet

Open questions, each with why it is open and what would close it.

How fast does the body clear it?

The sources RNAWiki checked hold nothing for this field.

Why it matters. Without this, nothing on this page can say how long anything lasts.

What would answer it

A stored source that records it, and a reviewer to sign it off.

Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.

Missing populations

Which groups were under-represented in the studies has not been recorded.

Why it matters. Recorded by the evidence model as a gap on this record.

What would answer it

A study that measures it, and a reviewer to sign it off.

Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.

Missing long-term data

No completed tested study window is recorded.

Why it matters. Recorded by the evidence model as a gap on this record.

What would answer it

A study that measures it, and a reviewer to sign it off.

Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.

No reviewed conclusion

RNAWiki has not yet published a reviewed conclusion for this use.

Why it matters. Recorded by the evidence model as a gap on this record.

What would answer it

A study that measures it, and a reviewer to sign it off.

Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.

Missing interaction studies

No interaction was found in the registers checked. Not finding one is not the same as showing there is none.

Why it matters. Recorded by the evidence model as a gap on this record.

What would answer it

A study that measures it, and a reviewer to sign it off.

Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.

Formulation uncertainty

Several salts, forms or products of Iron are recorded. Results from one form may not transfer to another.

Why it matters. Recorded by the evidence model as a gap on this record.

What would answer it

A study that measures it, and a reviewer to sign it off.

Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.

Mechanism not reviewed

No reviewed mechanism story exists for this substance.

Why it matters. Recorded by the evidence model as a gap on this record.

What would answer it

A study that measures it, and a reviewer to sign it off.

Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.

What happened in peopleRead from sources, not yet reviewed

Check any of this yourself

Every line above traced back to the study it came from. This is the technical layer, and the vocabulary changes here.

Where else this substance is registered

FDA substance identifier (UNII)
E1UOL152H7
CAS registry number
7439-89-6
PubChem compound
23925
ChEBI
18248
RxNorm concept
90176
EMA substance identifier
100000091283
European Chemicals Agency number
231-096-4
DrugBank
DB01592

Checks this page had to pass

  • Passed

    Identity resolved

    no open identity hold

  • Passed

    No unresolved merge across substance families

    no quarantine open

  • Passed

    Every public sentence names a source

    The opening statement carries the origin: Quoted from a stored source.

  • Not passed

    Trial roles classified for highlighted evidence

    No registered study is classified as testing this substance.

  • Passed

    No internal keys in reader text

    enforced by the copy-contract test over the rendered page

  • Passed

    Safety mode resolved

    The identity record classes it as a supplement ingredient; no medicines register records an approval.

  • Passed

    Canonical metadata present

    slug and display name present

What is missing or unclearRead from sources, not yet reviewed

How this medicine reached us

Kept near the foot of the page. A historical event moves up only when it changes something about this substance today.

What the approval register records

  • The earliest marketing start date recorded for a listed product is 20250101.

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Recorded evidence blocks (13)

What did Iron's largest trial (406902 people) and its longest (16 years) measure?


406902 people in Iron's largest registered study, 16 years in its longest registered window, measuring Change in Hb concentration from baseline to week 8. ClinicalTrials.gov · 2026-09-01

39 na, 27 phase4, 23 phase3, 11 phase2, 5 na or unstated, 3 phase1; NCT00223717; 2017-01; no ageing endpoint recorded. Last human test completed 2026, NCT05678647.

Interpretation These counts include studies where Iron was a comparison treatment, a background treatment or an exposure in an observational study, and the longest window may be a planned end date. Trial roles have not yet been classified for this record.

Show the evidence
  • na
    39
  • phase4
    27
  • phase3
    23
  • phase2
    11
  • na or unstated
    5
  • phase1
    3
1 more recorded row
  • Last recorded human test NCT05678647
    2026-03-01

recorded 2026-09-01 · last checked 2026-09-04

From yeast to human: where has Iron shown lifespan?


C. elegans: lifespan, Drosophila: lifespan, NHP: healthspan, yeast: mechanism-only, mouse: biomarker, rat: mechanism-only, dog: mechanism-only and human: biomarker (105): the rungs where Iron has a recorded finding. Europe PMC and ClinicalTrials.gov · organism ladder · 2026-09-01

Change in Hb concentration from baseline to week 8. — the recorded outcome words.

Yeast mechanism-onlyC. elegans lifespanDrosophila lifespanMouse biomarkerRat mechanism-onlyDog mechanism-onlyNon-human primate healthspanHuman biomarker
Show the evidence
  • C. elegans
    lifespan
  • Drosophila
    lifespan
  • NHP
    healthspan
  • yeast
    mechanism-only
  • mouse
    biomarker
  • rat
    mechanism-only
2 more recorded rows
  • dog
    mechanism-only
  • human NCT01017614
    biomarker; Change in Hb concentration from baseline to week 8.; 105

recorded 2026-09-01 · last checked 2026-09-04

12 of Iron's trials stopped: accrual/recruitment, funding/business, other?


accrual/recruitment (4), funding/business (3) and other (5): Iron's stop wording, clustered. ClinicalTrials.gov · 2026-09-01

"The study was terminated because of significant enrollment challenges"; 12 of 105 registered studies

Show the evidence

Trial

  • NCT00223938
    terminated; "The study was terminated because of significant enrollment challenges"
  • NCT00459225
    withdrawn; "Difficulty recruiting subjects"
  • NCT00497471
    terminated; "Follow-up end in 1999"
  • NCT01155375
    terminated; "Several factors contributed to significant challenges in enrollment and led the Sponsor to discontinue the AMAG-FER-CKD-251 study as designed."
  • NCT01155388
    terminated; "Several factors contributed to significant challenges in enrollment and led the Sponsor to discontinue the AMAG-FER-CKD-252 study as designed."
  • NCT01908543
    terminated; "Technical issues with availability of relevant personnel"
6 further recorded trials
  • NCT01975272
    terminated; "Disapointing randomization rate"
  • NCT02564796
    terminated; "COVID"
  • NCT02839096
    terminated; "Lack of funds, PI left University"
  • NCT03944733
    withdrawn; "The study was never started as a result of change of personnel and funding"
  • NCT05114278
    terminated; "Study suspended due to a new development; the project was no longer feasible."
  • NCT05981794
    withdrawn; "PI left institution and changed to new PI, there was no funding secured for this study."

recorded 2026-09-01 · last checked 2026-09-04

Human studies of Iron used iron (2 mg/kg/daily) — over how long?


Human studies of Iron used "iron (2 mg/kg/daily)". ClinicalTrials.gov · 2026-09-01

4 recorded entries; human; also "60 mg elemental iron", "Iron sulfate 105 mg", "100mg iron fumarate"

Show the evidence

human

  • NCT00497471
    iron (2 mg/kg/daily)
  • NCT02481375
    60 mg elemental iron
  • NCT02949765
    Iron sulfate 105 mg
  • NCT04008147
    100mg iron fumarate

recorded 2026-09-01 · last checked 2026-09-04

Did Iron move epigenetic age, and by how much?


epigenetic age: "Lymphocyte and neutrophil proportions were found to partially mediate the causal association of iron status with epigenetic age acceleration." Europe PMC · epigenetic clock search · 2026-02-01

9 recorded sentences; 2026, 2025, 2023; biomarker

Show the evidence
  • epigenetic age PMID 41686558
    2026; "Lymphocyte and neutrophil proportions were found to partially mediate the causal association of iron status with epigenetic age acceleration."

DunedinPACE

  • PMID 40362718
    2025; "In a random sample of women from the Sister Study (<i>n</i> = 1260) with measured serum iron (ferritin, iron, transferrin saturation), we used linear regression models to assess cross-sectional associations between standardized serum iron and three methylation-based biological aging metrics (GrimAgeAccel, PhenoAgeAccel, and DunedinPACE), with and without adjustment for smoking, alcohol, menopause…"
  • PMID 40362718
    2025; "In contrast, higher serum iron and transferrin saturation were inversely associated with the biological aging metrics (serum iron, DunedinPACE: -0.02, (-0.07, 0.03); PhenoAgeAccel: -0.04 (-0.10, 0.01); GrimAgeAccel: -0.05 (-0.10, -0.01); transferrin saturation (DunedinPACE: -0.01, (-0.06, 0.05); PhenoAgeAccel: -0.01 (-0.06, 0.05); GrimAgeAccel: -0.05 (-0.10, -0.01)))."

epigenetic clock

  • PMID 37146762
    2023; "Genetic correlations (Rg) and bidirectional causal effects between systemic iron status and epigenetic clocks have not been fully investigated, although observational studies have suggested systemic iron status is associated with human aging."
  • PMID 37146762
    2023; "We explored the genetic correlations and bidirectional causal effects between systemic iron status and epigenetic clocks."
  • GrimAge PMID 37146762
    2023; "Leveraging large-scale genome-wide association study summary-level statistics for 4 systemic iron status biomarkers (ferritin, serum iron, transferrin, and transferrin saturation) (N = 48,972) and 4 measures for epigenetic age (GrimAge, PhenoAge, intrinsic epigenetic age acceleration (IEAA), and HannumAge) (N = 34,710), genetic correlations, and bidirectional causal effects were estimated between…"
  • PhenoAge PMID 37146762
    2023; "The LDSC results illustrated Rg between serum iron and PhenoAge (Rg = 0.1971, P = 0.048) and between transferrin saturation and PhenoAge (Rg = 0.196, P = 0.0469)."

epigenetic clock

  • PMID 37146762
    2023; "Additionally, reverse MR study indicated no significant causal effect of epigenetic clocks on systemic iron status."
  • PMID 37146762
    2023; "All 4 iron status biomarkers had a significant or suggestively significant causal effect on epigenetic clocks, whereas reverse MR studies did not."

recorded 2026-02-01 · last checked 2026-09-04

More Iron was worse in human: at what point?


U-shaped in human: "Dose-response analysis revealed a U-shaped relationship for iron intake (inflection point: 11.7 mg/day)." Europe PMC · dose-response search · 2026-06-02

6 recorded sentences naming Iron; U-shaped, dose-response

Show the evidence

U-shaped

  • PMID 41775437
    "Dose-response analysis revealed a U-shaped relationship for iron intake (inflection point: 11.7 mg/day)."
  • PMID 42231585
    "According to the RCS analysis, a significant (<i>P</i> overall < .001, <i>P</i> nonlinearity < .001) non-linear U-shaped correlation was observed between all iron metabolism markers and severe SA-AKI."
  • PMID 41217822
    "We observed a U-shaped association between dietary iron intake and gastric cancer risk."
  • PMID 41217822
    "This U-shaped association was also observed in both sexes, in all types of dietary iron intake (i.e., heme and nonheme), and among individuals with noncardia gastric cancer."
  • PMID 41217822
    "We found a U-shaped association between dietary iron intake and gastric cancer risk."
  • dose-response PMID 41775437
    "Based on data from 4,370 adults in the National Health and Nutrition Examination Survey (NHANES 2017-2018), we conducted survey-weighted multivariable logistic regression to assess the associations between iron status indicators and kidney stone risk, and used restricted cubic splines to examine potential dose-response relationships."

recorded 2026-06-02 · last checked 2026-09-04

Could one person measure Iron's effect on decrease in supine systolic blood pressure?


Decrease in supine systolic blood pressure: measured in Iron's trials.

Interpretation decrease in supine systolic blood pressure is the recorded endpoint.

Show the evidence

biomarkers

  • decrease in supine systolic blood pressure; 2026-09-01
  • hemoglobin; 2026-09-01
  • incidence of diarrhea; 2026-09-01
  • whose rebleeds decreased from baseline by 50 at 12 months; 2026-09-01
  • cessation of bleeding; 2026-09-01
  • oxidative stress; 2026-09-01
14 more recorded rows
  • biomarkers
    incidence of placental malaria; 2026-09-01
  • biomarkers
    infant birth weight; 2026-09-01
  • biomarkers
    maximum change from baseline in hb during weeks 3 13; 2026-09-01
  • biomarkers
    hemoglobin levels; 2026-09-01
  • biomarkers
    symptom severity scale; 2026-09-01
  • biomarkers
    hemoglobin level; 2026-09-01
  • biomarkers
    hemoglobin concentration; 2026-09-01
  • biomarkers
    proportion recovered from moderate acute malnutrition; 2026-09-01
  • biomarkers
    maternal change in mid upper arm circumference; 2026-09-01
  • biomarkers
    infant birth length; 2026-09-01
  • biomarkers
    premature delivery; 2026-09-01
  • biomarkers
    psychomotor development; 2026-09-01
  • biomarkers
    systolic blood pressure; 2026-09-01
  • biomarkers
    complete blood count; 2026-09-01
  • human trials at or under30
    26
  • Not recorded for this substance
    a recorded half-life
  • smallest human trial
    0; NCT00459225; NA; the smallest recorded human enrolment at or below 30; the registry states no direction of its result; WITHDRAWN

Which of ampk levels, cessation of bleeding and complete blood count did Iron's trials measure?


ampk levels, cessation of bleeding and complete blood count lead 40 outcome terms across Iron's trials. ClinicalTrials.gov · 2026-09-01

whose rebleeds decreased from baseline by 50 at 12 months, cessation of bleeding, oxidative stress, incidence of placental malaria, infant birth weight and maximum change from baseline in hb during weeks 3 13 follow.

Show the evidence
  • decrease in supine systolic blood pressure
    1
  • hemoglobin
    1
  • incidence of diarrhea
    1
  • whose rebleeds decreased from baseline by 50 at 12 months
    1
  • cessation of bleeding
    1
  • oxidative stress
    1
14 more recorded rows
  • incidence of placental malaria
    1
  • infant birth weight
    1
  • maximum change from baseline in hb during weeks 3 13
    1
  • hemoglobin levels
    1
  • symptom severity scale
    1
  • hemoglobin level
    1
  • hemoglobin concentration
    1
  • proportion recovered from moderate acute malnutrition
    1
  • maternal change in mid upper arm circumference
    1
  • infant birth length
    1
  • premature delivery
    1
  • psychomotor development
    1
  • systolic blood pressure
    1
  • complete blood count
    1

recorded 2026-09-01 · last checked 2026-09-04

Which of Iron's 13 ongoing trials reports first?


13 registered trials of Iron are open; earliest completion 2025-01. ClinicalTrials.gov · 2026-09-01

Systolic blood pressure; Change in muscle strength; latest 2028-12-31

Show the evidence

Trial

  • NCT03042988
    "Overnight Trials With Heat Stress in Autonomic Failure Patients With Supine Hypertension"; n 20; "Systolic blood pressure"; 2026-12-30
  • NCT03991169
    "Oral Iron in Children With Chronic Kidney Disease"; n 40; "Change in muscle strength"; 2028-12-31
  • NCT04008147
    "Hepcidin and Glucose Metabolism"; n 30; "Serum hepcidin"; 2025-12-31
  • NCT05708170
    "Impact of Intravenous Iron on Musculoskeletal Function in Older Adults"; n 100; "Muscle Quality Index (MQI)"; 2027-01
  • NCT06427200
    "Efficacy and Safety of Lactoferrin in Heart Failure Patients"; n 114; "Change in health-related quality of life (HR-QoL)"; 2027-07
  • NCT06550362
    "Daily Iron vs Every-other-day Iron for Pediatric Patients With IDA"; n 100; "Hemoglobin stabilization"; 2027-05
7 further recorded trials
  • NCT06637137
    "Patient Blood Management in Patients Scheduled for Cardiac Surgery"; n 464; "Percentage of patients receiving RBC transfusion within post-operative day 7"; 2027-02-28
  • NCT06648018
    "Comparison of Nutritional Information With Iron-succinate Supplementation in Healthy Women"; n 80; "Ferritin blood test"; 2025-01
  • NCT06670963
    "Use of Epoetin Alfa and Iron Derisomaltose in Treatment of Anemia in Patients With Sepsis or Septic Shock: a Randomized Controlled Trial"; n 200; "Hemoglobin concentration difference at exit from the study"; 2027-04-01
  • NCT07237087
    "Masseter Muscle Stiffness After Heat Application and Percussion Therapy"; n 40; "Masseter muscle stiffness"; 2026-03-31
  • NCT07569601
    "The Effect of Heat Pads and Foam Rolling on Strength in Athletes."; n 38; "Force Production"; 2028-08-30
  • NCT07613190
    "Adjunctive Oral Iron Supplementation in Atopic Dermatitis"; n 124; "• Change in Eczema Area and Severity Index (EASI) score from baseline to week 12."; 2027-10
  • NCT07659184
    "IRONCARE: Iron Treatment in Older Patients With Hip Fractures"; n 528; "Fatigue"; 2028-09-30

recorded 2026-09-01 · last checked 2026-09-04

Which 38 trials of Iron posted no result?


Posted no result
38 of 38 completed trials
Registrations
NCT00998998, NCT00284700, NCT00822380, NCT01047098, NCT01092377 and NCT01507792, and 32 more
Completion dates
oldest 1996-07; newest 2024-08-31
Show the evidence

Trial

  • NCT00998998
    1996-07
  • NCT00284700
    2001-05
  • NCT00822380
    2004-11
  • NCT01047098
    2010-04
  • NCT01092377
    2010-12
  • NCT01507792
    2011-01
14 further recorded trials
  • NCT01017614
    2012-08
  • NCT01913808
    2013-01
  • NCT01414374
    2013-03
  • NCT01119612
    2013-05
  • NCT01308112
    2013-05
  • NCT01443624
    2013-08
  • NCT01670955
    2013-12
  • NCT01991626
    2014-08
  • NCT00558454
    2014-11
  • NCT01131624
    2015-04
  • NCT01820052
    2015-12
  • NCT01857011
    2016-06
  • NCT01787526
    2016-08
  • NCT02120599
    2016-08

At the median, Iron's trials enrolled 100 people — anything larger?


Median enrolment
100
Largest enrolment
406902
Registered trials counted
104

Was Iron studied with fasting and exercise?


fasting and exercise are named in Iron's label sentences: "A randomized, open-label, two-cohort, two-period, single-dose crossover study was conducted to assess the effect of food on iron absorption when 500 mg ferric citrate hydrate (approximately 120 mg of ferric iron) was administered under fasted and fed (immediately after a meal) conditions." openfda-label+europepmc · 2026-07-17

2 recorded statements; fasting, exercise

Show the evidence
  • fasting
    A randomized, open-label, two-cohort, two-period, single-dose crossover study was conducted to assess the effect of food on iron absorption when 500 mg ferric citrate hydrate (approximately 120 mg of ferric iron) was administered under fasted and fed (immediately after a meal) conditions.
  • exercise
    The Effect of Oral sucRosomIal Iron on exerciSE Capacity and Quality of Life in Patients With Heart Failure (RISE-HF; NCT06270498) is a randomized, placebo-controlled, double-blind study enrolling 60 patients with HF with left ventricular ejection fraction <50%, ID (transferrin saturation (TSAT) < 20%), ferritin <400 μg/L and hemoglobin (Hb) 10-16 g/dL.

recorded 2026-07-17 · last checked 2026-09-04

What is recorded about Iron and mTOR?


"Further, iron overload activated mTOR signaling and downregulated AMP-activated protein kinase (AMPK) phosphorylation." — where Iron and mTOR appear together. Europe PMC · pathway abstract search · 2026-07-02

mTOR, AMPK, autophagy, sirtuin, NAD+; PMID 42393564, 41777735, 40109363, 41692973

Show the evidence
  • mTOR PMID 42393564
    "Further, iron overload activated mTOR signaling and downregulated AMP-activated protein kinase (AMPK) phosphorylation."
  • AMPK PMID 42393564
    "Further, iron overload activated mTOR signaling and downregulated AMP-activated protein kinase (AMPK) phosphorylation."
  • autophagy PMID 41777735
    "Current evidence demonstrates that SMN loss arises from the coordinated activation of multiple programmed cell death (PCD) pathways-including apoptosis, necroptosis, pyroptosis, ferroptosis, and impaired autophagy-regulated by oxidative stress, mitochondrial dysfunction, calcium overload, iron dyshomeostasis, and inflammasome activation."
  • sirtuin PMID 40109363
    "Sirtuin 1 (SIRT1), a NAD + -dependent histone deacetylase, has emerged as a pivotal epigenetic regulator with the potential to regulate ferroptosis through a wide array of genes intricately associated with lipid metabolism, iron homeostasis, glutathione biosynthesis, and redox homeostasis."
  • NAD+ PMID 40109363
    "Sirtuin 1 (SIRT1), a NAD + -dependent histone deacetylase, has emerged as a pivotal epigenetic regulator with the potential to regulate ferroptosis through a wide array of genes intricately associated with lipid metabolism, iron homeostasis, glutathione biosynthesis, and redox homeostasis."
  • sirtuin PMID 41692973
    "We further highlight the therapeutic potential of targeting ferritinophagy and propose future research directions aimed at harnessing this pathway for the treatment of organ injuries.<b>Abbreviations:</b> 3-MA: 3-methyladenine; ACO1/IRP1: aconitase 1; AKI: acute kidney injury; ARDS: acute respiratory distress syndrome; ATG: autophagy related; BECN1: beclin 1; CARM1/PRMT4: coactivator associated…"
7 more recorded rows
  • autophagy PMID 41692973
    "We further highlight the therapeutic potential of targeting ferritinophagy and propose future research directions aimed at harnessing this pathway for the treatment of organ injuries.<b>Abbreviations:</b> 3-MA: 3-methyladenine; ACO1/IRP1: aconitase 1; AKI: acute kidney injury; ARDS: acute respiratory distress syndrome; ATG: autophagy related; BECN1: beclin 1; CARM1/PRMT4: coactivator associated…"
  • mTOR PMID 42364854
    "GRk1 activated AMPK while suppressing mTOR signaling, leading to NCOA4-dependent ferritinophagy, ferritin degradation, and intracellular iron accumulation."
  • AMPK PMID 42364854
    "GRk1 activated AMPK while suppressing mTOR signaling, leading to NCOA4-dependent ferritinophagy, ferritin degradation, and intracellular iron accumulation."
  • mTOR PMID 41176258
    "This process is modulated by signaling networks such as MAPK, cGAS-STING, NF-κB, AMPK/mTOR, and NRF2, which link iron metabolism to inflammatory responses."
  • AMPK PMID 41176258
    "This process is modulated by signaling networks such as MAPK, cGAS-STING, NF-κB, AMPK/mTOR, and NRF2, which link iron metabolism to inflammatory responses."
  • autophagy PMID 41925978
    "Aromatic amino acid metabolism modulates autophagic responses and a determinant of GBM susceptibility to iron deprivation."
  • sirtuin PMID 41527519
    "The results showed that compared with the model group, the EA treatment group and the Fer-1 (iron inhibitor) treatment group revealed improved ferroptosis and memory function in hippocampal neurons, while the EX527 (SIRT1 inhibitor) treatment group did not reveal any improvement."

recorded 2026-07-02 · last checked 2026-09-04

Where it is registered
Identifiers, relations and other names

The exact record

PubChem CID
23925
CAS number
7439-89-6
RxCUI
90176
InChIKey
XEEYBQQBJWHFJM-UHFFFAOYSA-N
Trade name
Ferrum Metallicum, Ferrum Met, Ferrum Metallicum 6x, Ferrum Sidereum 7x, Ferrum Sidereum 30x, Real Summer, Ferrum Pentas, Bestmade Natural Products Ferr Met, Ferrum 0.4, Ferrum 5X, Ferrum Metallicum / Ferrum Met / Ferrum Metallicum 6x / Ferrum Sidereum 7x / Ferrum Sidereum 30x / Real Summer, Ishancare Heating Pad
Salt form
FERRUM PENTAS 7X, 11X, 18X, 30X, HEATING PAD
Also called
Iron Powder, CARBONYL IRON, ELECTROLYTIC IRON, FERRUM METALLICUM [HPUS], IRON [HSDB], IRON [MART.], IRON [MI], IRON [VANDF], IRON, CARBONYL, IRON, CARBONYL [FCC]
Development code
FE
Sources (10)

Sources

  • ClinicalTrials.gov clinicaltrials.gov ·
  • ClinicalTrials.gov ClinicalTrials.gov API v2 snapshot 2026-09-01T09:00:05 ·
  • this record's own fields 2,3,5 ·
  • Europe PMC dose-response search ·
  • Europe PMC epigenetic clock search ·
  • Europe PMC pathway abstract search ·
4 more sources

ClinicalTrials.gov — US Government work · Europe PMC — metadata only, under the recorded legal gate · derived from this page's own recorded fields; no external licence · mixed register set; per-register licences in docs/specs/corpus-20k-sources.md · openFDA / DailyMed — US Government work

How these records are assembled · Which registers were checked

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  • public claims reviewed: 0 reviewed claim(s); drafts are never rendered
  • source coverage passed: 10 source rows
  • no critical contamination: no quarantine open
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