This page shows what was measured, who it was measured in, and what that does not settle.
What Boron does in the body
A trace element sold to raise testosterone — whose critical animal toxicity is testicular
Boron in food and water is absorbed almost completely and circulates as boric acid, a small uncharged molecule that spreads through body water and leaves in urine within a day. It has no receptor and no enzyme of its own. What it does chemically is form loose, reversible bonds with pairs of adjacent hydroxyl groups — the arrangement found in sugars, in some glycoproteins, and in the vitamin-derived cofactors NAD and SAM. That is a real and specific chemistry, and it is also non-specific enough that it does not point at any particular biological job. Sixty years after people began looking, none has been agreed on.
What happened in people
A PRISMA systematic review of minerals in athletic performance found four boron experiments and rated none of them strong
✎ 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 recorded finding that sits closest to something a person would notice. Written into the record, not signed off, and it carries no population or interval.
48 registered substances share the start of this name, which is why a search for it can return more than one thing.
FDA substance registry · S043P4DV22 · read 2026-08-29
Where each sentence above came from
No recorded sentence describes the change this makes in a way that stands on its own. The page opens with what it is taken for instead, and the recorded explanation follows below.
Shown as the opening line on this page.
A limit recorded against this substance. Not signed off as a reviewed claim.
The four opening statements run to 139 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.
Protein
A protein is a folded chain your body builds to do a specific job.
A picture of it, and where the picture fails
A protein is like a tool bent into one shape for one task.
Where that stops being true. A tool keeps its shape. A protein can change shape and stop working.
What people get wrong. Protein in food and a protein in the body are related but not the same thing.
A polymer of amino acids folded into a defined structure that determines its function.
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 people◇Read 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.
Plasma and urinary calcium and magnesium, and serum 17beta-oestradiol and testosterone
✓ The study showed what it set out to show
Who was studied
Nielsen boron depletion-repletion study in postmenopausal women
How many people
12
Study design
Controlled metabolic ward feeding study, 119 days depletion then 48 days repletion
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Repletion with 3 mg/day boron reduced total plasma calcium and urinary calcium and magnesium excretion and elevated serum 17beta-oestradiol and testosterone, after 119 days on 0.25 mg boron per 2,000 kcal
Repeated elsewhere
Unreplicated
What this does not prove. Meeting one endpoint in one population does not carry to other goals or other people.
The limits of this study, and where it came from
Main limit. Twelve postmenopausal women, no control group, and a design in which every participant was first made boron-deficient. Later studies in the same programme used diets low in magnesium and marginally adequate in copper, which confounds the mineral findings.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Oral capsule or tablet, typically 3 to 10 mg elemental boron as citrate, glycinate, aspartate or calcium fructoborate
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
Effect of mineral and trace element supplementation on athletic performance
✗ The study did not show it
Who was studied
Heffernan 2019 systematic review of minerals in athletic performance
How many people
0
Study design
PRISMA systematic review, six databases and grey literature
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
From 17,433 articles, 130 experiments were included, of which 4 concerned boron. Only iron and magnesium contained articles of sufficient quality to be rated strong. Little evidence was found to support supplementation for performance
Repeated elsewhere
Replicated
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. Oral capsule or tablet, typically 3 to 10 mg elemental boron as citrate, glycinate, aspartate or calcium fructoborate
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
Dietary boron intake and 24-hour urinary boron excretion by dietary pattern
✓ The study showed what it set out to show
Who was studied
Stubing 2026 cross-sectional intake and excretion study
How many people
0
Study design
Cross-sectional, long-term omnivores, lacto-ovo-vegetarians and vegans
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Creatinine-corrected urinary boron 1,559 ug/g in vegans, 1,235 in lacto-ovo-vegetarians and 919 in omnivores; intake correlated with excretion at r = 0.79 in vegans and r = 0.74 in omnivores, both p < 0.001
Repeated elsewhere
Unreplicated
What this does not prove. Meeting one endpoint in one population does not carry to other goals or other people.
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. Oral capsule or tablet, typically 3 to 10 mg elemental boron as citrate, glycinate, aspartate or calcium fructoborate
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
RNAWiki holds 4 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 people◇Read 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.
□Living longer, or avoiding a major eventNo evidence recorded. Death, a heart attack, a stroke, a hospital stay.No registered study measures this.
□What a body can do day to dayNo evidence recorded. Walking, dressing, breathing, recovering.No registered study measures this.
□Measured performanceNo evidence recorded. How much was lifted, how far was run, how fast.No registered study measures this.
□Symptoms and quality of lifeNo evidence recorded. Pain, tiredness, mood, sleep, as the person rated it.No registered study measures this.
□A number that stands in for healthNo evidence recorded. Cholesterol, blood sugar, bone density. A stand-in, not the thing itself.No registered study measures this.
■A step measured inside a personEvidence recorded. Something measured in human tissue or human cells.A human record sits on the stored organism ladder.
■AnimalsEvidence recorded. Mice, rats, dogs. Useful for ideas, not proof about people.Stored records in Drosophila (fruit fly), Mouse, Rat. A result in animals says what to test next. It does not say what happens in people.
■Cells in a dishEvidence recorded. Cells or chemistry on a bench, far from a whole body.Stored mechanism abstracts describe steps measured in cells or tissue.
□A guess from softwareNo 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 changes in the body◇Read from sources, not yet reviewed
The path through the body
From what a person takes to what changes. A solid line is a step measured in people. A dashed line is a step nobody has measured that way.
Start
Boron
What a person takes: Oral capsule or tablet, typically 3 to 10 mg elemental boron as citrate, glycinate, aspartate or calcium fructoborate.
The measurement behind this step
A simple oral supplement. The counterion varies between products and the absorbed species does not: all forms are hydrolysed and absorbed as boric acid with near-complete bioavailability, so claims of superior absorption for one salt over another have no mechanism behind them. Labels differ in whether the stated milligram figure is elemental boron or the whole salt, which is worth checking before comparing a dose to an upper limit.
Getting in
Absorbed almost completely, whatever form it is in
Citrate, glycinate, borate — the gut converts all of them to the same thing and absorbs nearly all of it.
╌╌Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.
The measurement behind this step
Ingested boron compounds are hydrolysed in the gastrointestinal tract and absorbed as boric acid with near-complete bioavailability. The differences between marketed forms are differences in the counterion, not in what reaches the bloodstream.
It is small and uncharged, so it spreads evenly through the water in the body rather than concentrating anywhere.
╌╌Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.
The measurement behind this step
Boric acid is a small, uncharged, highly water-soluble molecule that distributes in total body water without a transporter and without significant tissue accumulation, other than modest concentration in bone.
Its one real chemical trick is latching onto two neighbouring OH groups — a pattern found in sugars and in several cofactors.
╌╌Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.
The measurement behind this step
As a weak Lewis acid, boric acid forms reversible mono- and diester complexes with cis-diol groups on ribose, on glycoproteins and on cofactors including NAD and S-adenosylmethionine. No specific binding partner has been identified as the physiologically relevant one in humans.
Effects appear on repletion of a depleted person, and only then
The measured human effects all come from studies where boron was first removed from the diet and then put back.
──Measured in people. Written by a person from the study named beside the step. Not signed off as a reviewed claim.
The measurement behind this step
In depletion-repletion studies, 3 mg/day of boron reduced plasma calcium and urinary calcium and magnesium excretion and raised serum 17beta-oestradiol and testosterone in postmenopausal women, and raised erythrocyte superoxide dismutase, ceruloplasmin and plasma copper in a mixed group on a magnesium-low diet. No study has shown a comparable effect of supplementation in people whose intake was already ordinary.
It leaves in urine quickly, which is why urinary excretion tracks intake so closely and why a supplement mostly raises what you excrete.
╌╌Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.
The measurement behind this step
Elimination is almost entirely renal and rapid, with 24-hour urinary excretion correlating with intake at r = 0.74-0.79 in omnivores and vegans. The European tolerable upper intake level is 10 mg/day, and the critical toxicological endpoints in animals are testicular and developmental toxicity.
No suggested links are held for this record, so nothing is hidden from this path.
What we know
The record describes 5 steps from taking it to an effect in a person.
How we know it
Each step names the study behind it in the technical detail beside it.
What this does not prove
A change inside the body is a reason to look. It is not a result in a person.
Why it matters
A reader can see exactly where the chain stops being measured in people.
What we still do not know
No reviewed claim binds any of these steps to a named population.
What is missing or unclear◇Read 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.
Men taking it for testosterone, people taking it for osteoarthritis or bone density, and everyone else, involuntarily, from fruit, nuts, legumes and drinking water.
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
Sixty years of work has not established boron as an essential nutrient or identified a human function for it
No Recommended Dietary Allowance or Adequate Intake has ever been set, because no requirement has been demonstrated
The athletic performance literature contains four boron experiments and none of sufficient quality to be rated strong
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 take◇Read 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 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.
Something else had to happen too
In the studies it was paired with training, a diet or another treatment.
On this record: The measured human effects all come from studies where boron was first removed from the diet and then put back.
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.
The product may not be what it says
Contents of a sold product are not always what the label states.
On this record: This is sold as a supplement, so no agency checked what is in a given tub before it was sold.
Other reasons RNAWiki checked and found nothing for (9)
It was studied for a different goal
The studies measured something else entirely. Nothing in this record points to this reason.
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.
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.
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 take◇Read 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
Oral capsule or tablet, typically 3 to 10 mg elemental boron as citrate, glycinate, aspartate or calcium fructoborate
✎ 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
A simple oral supplement.
✎ 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. The rest of the recorded wording: The counterion varies between products and the absorbed species does not: all forms are hydrolysed and absorbed as boric acid with near-complete bioavailability, so claims of superior absorption for one salt over another have no mechanism behind them. Labels differ in whether the stated milligram figure is elemental boron or the whole salt, which is worth checking before comparing a dose to an upper limit.
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 take◇Read from sources, not yet reviewed
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.
·Worth asking a clinician aboutWritten into the record from the studies named on this page
The European tolerable upper intake level is 10 mg per day. Acute boric acid poisoning at far higher exposures causes vomiting, diarrhoea, a characteristic erythematous rash and, in severe cases, renal failure. The endpoints that set the regulatory limits are chronic: testicular toxicity in two-year rat and dog feeding studies, with no-observed-adverse-effect levels of 17.5 and 8.8 mg boron per kilogram per day respectively, and developmental toxicity with reduced fetal body weight in rodents. A re-derivation using chemical-specific uncertainty factors arrived at a tolerable daily intake of 0.13 mg per kilogram per day, based on rat developmental toxicity. Because clearance is renal, impaired kidney function raises exposure at any given intake.
Nobody counted how many people took this and were fine, so this cannot be turned into a rate.
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 unclear◇Read 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
Oral capsule or tablet, typically 3 to 10 mg elemental boron as citrate, glycinate, aspartate or calcium fructoborate
✎ 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
A recorded note compares this form with the others that are sold. It is kept below, word for word.
§ A fixed RNAWiki sentence
Where this came from
Wording RNAWiki always uses, not a finding about this substance.
The recorded note, unchanged: The counterion varies between products and the absorbed species does not: all forms are hydrolysed and absorbed as boric acid with near-complete bioavailability, so claims of superior absorption for one salt over another have no mechanism behind them. Labels differ in whether the stated milligram figure is elemental boron or the whole salt, which is worth checking before comparing a dose to an upper limit.
No source is stored against this line.
What is recorded as being sold
43 products list this as an active ingredient in the United States drug directory. 16 of them contain it and nothing else.
FDA National Drug Code directory · 37662-2745 · read 2026-08-29
They are sold as liquid, pellet, tablet and tablet, chewable, taken oral.
FDA National Drug Code directory · 37662-2745 · read 2026-08-29
29 published labels name it as an active ingredient. 2 of them describe this substance alone, which is where its own label text on this page comes from.
US prescribing information · f5cf9032-ab22-2853-e053-2995a90a244b · read 2026-08-29
Those labels are classed as human otc drug and human prescription drug.
US prescribing information · f5cf9032-ab22-2853-e053-2995a90a244b · read 2026-08-29
3966 marketed supplement labels list this ingredient, classed as mineral and other combinations.
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.
Foliflex is oral at HOW SUPPLIED: Foliflex TM are yellow with slightly brown speckled, oblong, coated caplets., recorded as fda label in effect 2024-11-27 in the United States.
US prescribing information · cba98d1a-8cf9-39d9-e053-2995a90ae8bb · read 2026-08-30
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 take◇Read 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.
Pick one goal. One goal only. Two at once cannot be told apart afterwards.
Pick one thing to watch. No registered study lists a measure RNAWiki could read for this.
Measure before you start. Take the same measurement several times first. One reading is not a starting point.
Know the swing. Write down how much it moves on its own across a normal week.
Change one thing. Change nothing else at the same time, including training and sleep.
Give it the study length. No finished study window is recorded, so no length is suggested here.
Track whether you took it. Missed days are the most common reason a home test shows nothing.
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.
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 unclear◇Read from sources, not yet reviewed
Claims that go past the evidence
Things said about this substance that sound reasonable, and the exact step that is missing between the evidence and the claim.
✗Goes past the evidence
That a testosterone rise on repletion of a depleted postmenopausal woman predicts anything in a boron-replete man
Why it sounds right. It follows from something real on this page: a body step, an animal result or a related finding.
The missing step. Nobody measured this in people for this use, or the study that did measure it did not show it.
What would change this
A study in people, for this exact use, measuring this exact thing, that a reviewer signs off.
RNAWiki has not yet published a reviewed conclusion for this use.
✗Goes past the evidence
That cis-diol binding chemistry constitutes a physiological role, when no human enzyme, receptor or deficiency syndrome has been identified
Why it sounds right. It follows from something real on this page: a body step, an animal result or a related finding.
The missing step. Nobody measured this in people for this use, or the study that did measure it did not show it.
What would change this
A study in people, for this exact use, measuring this exact thing, that a reviewer signs off.
RNAWiki has not yet published a reviewed conclusion for this use.
✗Goes past the evidence
That the marketed forms differ meaningfully, when all are absorbed as boric acid with near-complete bioavailability
Why it sounds right. It follows from something real on this page: a body step, an animal result or a related finding.
The missing step. Nobody measured this in people for this use, or the study that did measure it did not show it.
What would change this
A study in people, for this exact use, measuring this exact thing, that a reviewer signs off.
RNAWiki has not yet published a reviewed conclusion for this use.
✗Goes past the evidence
That an element with no established requirement can be deficient in an ordinary diet, when urinary excretion tracks intake closely across omnivores, vegetarians and vegans
Why it sounds right. It follows from something real on this page: a body step, an animal result or a related finding.
The missing step. Nobody measured this in people for this use, or the study that did measure it did not show it.
What would change this
A study in people, for this exact use, measuring this exact thing, that a reviewer signs off.
RNAWiki has not yet published a reviewed conclusion for this use.
What is missing or unclear◇Read from sources, not yet reviewed
What nobody knows yet
Open questions, each with why it is open and what would close it.
How much did people take in the studies?
The sources RNAWiki checked hold nothing for this field.
Why it matters. A result belongs to an amount. Without the amount the result floats free.
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.
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 Boron 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 people◇Read 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.
Every line above can be traced to the study named beside it. Follow the link and read it.
The testosterone finding came from repleting depleted postmenopausal women
In plain words
The study behind the testosterone claim fed twelve postmenopausal women a boron-poor diet for four months and then added 3 mg a day. Their oestradiol and testosterone rose — from a deficiency, in women.
What was measured
That a rise in testosterone on repletion of an experimentally depleted postmenopausal woman predicts a rise in a boron-replete man taking a supplement
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Nielsen describes the first nutritional boron study in humans: 12 postmenopausal women were fed a diet providing 0.25 mg boron per 2,000 kcal for 119 days, then the same diet with a 3 mg/day boron supplement for 48 days. Supplementation reduced total plasma calcium and urinary calcium and magnesium excretion, and elevated serum 17beta-oestradiol and testosterone. A second study in five men over 45, four postmenopausal women and five postmenopausal women on oestrogen therapy used a boron-low diet (0.23 mg/2,000 kcal) for 63 days followed by 3 mg/day for 49 days, but that diet was low in magnesium and marginally adequate in copper throughout, and the reported findings were higher erythrocyte superoxide dismutase, serum ceruloplasmin and plasma copper on repletion. A third study repeated the design with adequate magnesium and copper and reported effects centred on oestrogen therapy and copper status. The design in every case is depletion followed by repletion. That answers what happens when a boron-deficient person is given boron. It does not answer what happens when a boron-replete person takes more, which is what the supplement is sold for.
Written into the record, not signed off as a reviewed claim
The critical animal toxicity endpoint is testicular
In plain words
In two-year feeding studies, the effect that sets boron safe limits is damage to the testes — in a compound sold to raise testosterone.
What was measured
No-observed-adverse-effect levels for testicular toxicity in two-year rat and dog studies, and benchmark dose limits for fetal body weight reduction
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Hasegawa et al. re-derived a tolerable daily intake for boron using chemical-specific uncertainty factors. No-observed-adverse-effect levels of 17.5 and 8.8 mg boron per kilogram per day for the critical effect of testicular toxicity were identified in two-year rat and dog feeding studies. The 95% lower confidence limit of the benchmark dose for a 5% reduction in fetal body weight was 44.9 mg/kg/day in mice and 10.3 mg/kg/day in rats. Applying measured interspecies differences in boron clearance and variability in glomerular filtration rate in pregnant women, overall uncertainty factors were 68 for rat testicular toxicity, 40 for dog testicular toxicity, 247 for mouse developmental toxicity and 78 for rat developmental toxicity, and the authors concluded that 0.13 mg boron per kilogram per day is the most appropriate tolerable daily intake, based on rat developmental toxicity. Testicular and developmental toxicity being the endpoints that define the safe boundary is a fact worth stating next to the marketing.
Written into the record, not signed off as a reviewed claim
Not an essential nutrient, and no recommended intake
In plain words
Boron has never been classified as essential for humans, has no Recommended Dietary Allowance, and the European upper limit is 10 mg a day.
What was measured
Nutritional classification, existence of a Recommended Dietary Allowance, and the European tolerable upper intake level
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
A 2026 review of boron in the diet and as a supplement states plainly that boron is not currently classified as an essential nutrient, while describing it as biologically important and surveying claimed effects on bone, cognition, mineral and hormonal metabolism, antioxidant defence, body weight and inflammation. The European Food Safety Authority tolerable upper intake level for boron is 10 mg per day. There is no Recommended Dietary Allowance and no Adequate Intake, because establishing either requires an identified requirement, and no requirement has been established. Everything about boron supplementation therefore sits on top of an intake with no defined target.
Written into the record, not signed off as a reviewed claim
Diet already supplies it, and how much depends on what you eat
In plain words
Vegans excrete substantially more boron than omnivores, because plant foods are where boron comes from. Most people are getting it without a supplement.
What was measured
Creatinine-corrected 24-hour urinary boron excretion by dietary pattern, and correlation with measured intake
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Stubing et al. measured boron intake and 24-hour urinary excretion in long-term omnivores, lacto-ovo-vegetarians and vegans. Creatinine-corrected urinary boron excretion was highest in vegans at 1,559 micrograms per gram creatinine (interquartile range 1,151-2,057), then lacto-ovo-vegetarians at 1,235 (878-1,815), then omnivores at 919 (639-1,381). Boron intake correlated strongly with 24-hour urinary excretion in vegans (r = 0.79) and omnivores (r = 0.74), both p < 0.001, and less strongly in lacto-ovo-vegetarians (r = 0.43). Higher urinary boron excretion was associated with higher potassium excretion in all dietary patterns and with phosphorus excretion in vegans (r = 0.57, p < 0.001). Fruit, nuts, legumes, pulses and drinking water are the sources. The study is also a reminder that urinary excretion tracks intake closely, because absorption is near complete and clearance renal — which is why a supplement raises excretion rather than accumulating.
Written into the record, not signed off as a reviewed claim
The systematic review of minerals in athletic performance found four boron studies
In plain words
A review of 130 experiments on minerals and trace elements in exercise found only four on boron, and rated the evidence strong for only iron and magnesium.
What was measured
Number of included boron experiments and assigned evidence strength in a PRISMA systematic review of 130 experiments
Effect estimate
No reviewed effect estimate exists for this record.
Limits
This entry records a failure.
From the source
Heffernan et al. systematically reviewed the role of minerals and trace elements in exercise and athletic performance across six databases and grey literature, following PRISMA and preregistered on PROSPERO. From 17,433 articles, 130 experiments from 128 studies were included: iron 29, magnesium 22, phosphate 17, sodium 15, chromium 12, calcium 11, zinc 9, selenium 5, multi-mineral 5, and boron 4. Only iron and magnesium included articles of sufficient quality to be assigned a strong rating. The authors conclude that there is little evidence to support mineral and trace element supplementation to improve physiological markers of athletic performance, with the possible exception of iron in particular biological situations and magnesium, and that more high-quality research is required before support can be given for the rest. Four studies is the entire evidence base a performance claim for boron can draw on, and none of it was rated strong.
Written into the record, not signed off as a reviewed claim
A real chemistry that does not identify a job
In plain words
Boron genuinely binds to pairs of neighbouring hydroxyl groups, which are everywhere in biology. That is a mechanism looking for a function rather than a function with a mechanism.
What was measured
That cis-diol binding chemistry establishes a physiological role for boron in humans, when no enzyme, receptor or deficiency syndrome has been identified
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Boric acid forms reversible esters with cis-diol groups, an interaction that is chemically well characterised and underlies boron essential structural role in the plant cell wall, its use in boronic-acid drug design, and its ability to interact with ribose-bearing cofactors including NAD and S-adenosylmethionine. In humans this chemistry has been used to propose roles in hormone metabolism, bone formation, inflammation and oxidative defence, and it is the reasoning behind the supplement claims. It has not produced an identified human enzyme, receptor, transporter or deficiency syndrome. The distance between "this molecule reacts with a common chemical group" and "this molecule has a physiological role in people" is exactly the distance this site exists to mark, and for boron it has not been closed in sixty years of looking.
This order is fixed in code and does not count clicks or time on the page.
What is not here
6 questions this page could not answer
These sections were prepared and left out because there was nothing to put in them. They are listed rather than hidden, so the gaps in this record are visible.
What was measured, goal by goal — found nothing in the sources checked.
Felt, measured, or meaningful — found nothing in the sources checked.
How long anything takes — found nothing in the sources checked.
What it may clash with — found nothing in the sources checked.
Other ways to the same goal — found nothing in the sources checked.
What changed on this page — found nothing in the sources checked.
The record as stored
The full record, for auditing
Everything above is built from what is below. This layer keeps the technical vocabulary, record identifiers and every stored row, so a reader who wants to check the page can.
The older medicine-wide conclusion held in this record
Written for a clinical reader, and about the medicine as a whole rather than about one indication, population and set of trials. RNAWiki does not treat it as a programme conclusion and no reviewer has signed it off in that form. It is here word for word because it is what the record holds.
A trace element not classified as essential, with no Recommended Dietary Allowance, whose testosterone reputation rests on a repletion study in twelve boron-depleted postmenopausal women, and whose critical toxicity endpoint in two-year animal feeding studies is testicular.
Recorded evidence blocks (6)
Q1
What did Boron's largest trial (100 people) and its longest (14 months) measure?
100 people in Boron's largest registered study, 14 months in its longest registered window, measuring number of the participants with complete epithelization of diabetic foot ulcer. ClinicalTrials.gov · 2026-09-01
1 phase1; NCT02087215; 2015-03; no ageing endpoint recorded
Interpretation These counts include studies where Boron 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
phase1
1
recorded 2026-09-01 · last checked 2026-09-04
Q2
From Drosophila to human: where has Boron shown biomarker?
Interpretation number of the participants with complete epithelization of diabetic foot ulcer — the recorded outcome words.
Show the evidence
Drosophila
biomarker
mouse
mechanism-only
rat
mechanism-only
humanNCT02087215
mechanism-only; number of the participants with complete epithelization of diabetic foot ulcer; 1
recorded 2026-09-01 · last checked 2026-09-04
Q3
More Boron was worse in human: at what point?
Hormetic in human: "Biochemistry and biomedical studies restarted in the early 1990s first unveiled antioxidant, anti-inflammatory, nootropic, anticancer, and antigenotoxic properties of borates including borax (sodium tetraborate decahydrate), boric acid and boron esters at low dosage, and then clearly established hormetic response of…" Europe PMC · dose-response search · 2026-06-01
5 recorded sentences naming Boron; hormetic, U-shaped, dose-response
Show the evidence
hormeticPMID 42223354
"Biochemistry and biomedical studies restarted in the early 1990s first unveiled antioxidant, anti-inflammatory, nootropic, anticancer, and antigenotoxic properties of borates including borax (sodium tetraborate decahydrate), boric acid and boron esters at low dosage, and then clearly established hormetic response of these compounds."
U-shapedPMID 38634522
"The effect of the U-shaped cavity of conformationally flexible chiral Lewis acidic boron-based catalysts in multiselective Diels-Alder reactions was investigated."
hormetic
PMID 36878460
"Boron is shown in the present review to induce hormetic dose responses in a broad range of biological models, organ systems and endpoints."
PMID 36878460
"The re-exploration of boron's bioactivity as seen through hormetic mechanisms may also underscore the value of this approach to the assessment of micronutrient effects in human health and disease."
dose-responsePMID 41304983
"Growth inhibition and GI<sub>50</sub> values were most potent for the <b>meta 7</b> side-product. <b>Conclusions:</b> Beyond the cancer cell line inhibition and dose-response capabilities, the real therapeutic potential of these borylated drugs lies in their switch on/switch off activation under boron neutron capture therapy (BNCT) radiotherapeutic conditions, thus providing an important area of…"
recorded 2026-06-01 · last checked 2026-09-04
Q4
At the median, Boron's trials enrolled 100 people — anything larger?
Median enrolment
100
Largest enrolment
100
Registered trials counted
1
Q5
Was Boron studied with fasting?
fasting is named in Boron's label sentences: "Following collection of a fasting blood sample, subjects received either placebo or acute bolus of 11.6 mg boron (given as 102.6 mg sodium tetraborate decahydrate) together with a standard fat-rich meal." openfda-label+europepmc · 2002-11-01
1 recorded statement; fasting
Show the evidence
fasting
Following collection of a fasting blood sample, subjects received either placebo or acute bolus of 11.6 mg boron (given as 102.6 mg sodium tetraborate decahydrate) together with a standard fat-rich meal.
recorded 2002-11-01 · last checked 2026-09-04
Q6
What is recorded about Boron and sirtuin?
"Studies suggest that TEs, including zinc, selenium, boron, manganese, and molybdenum, and their NPs, can potentially counteract ACT-induced toxicity by inhibiting oxidative stress-mediated pathways, including NF-κB/TLR4/MAPK/NLRP3, STAT-3/NLRP3, Bcl-2/Bid/p53/caspases, and LC3/Beclin-1/CHOP/ATG6, while also upregulating protective…" — where Boron and sirtuin appear together. Europe PMC · pathway abstract search · 2024-11-12
"Studies suggest that TEs, including zinc, selenium, boron, manganese, and molybdenum, and their NPs, can potentially counteract ACT-induced toxicity by inhibiting oxidative stress-mediated pathways, including NF-κB/TLR4/MAPK/NLRP3, STAT-3/NLRP3, Bcl-2/Bid/p53/caspases, and LC3/Beclin-1/CHOP/ATG6, while also upregulating protective signaling pathways like Sirt1/PPAR-γ/PGC-1α/FOXO-3 and…"
PMID 39531139
"Sirtuins, known as the longevity genes, were also activated from boron treatment."
mTORPMID 36308567
"In the present study, it was aimed to investigate the anti-cancer properties of boron-containing DPD in SKOV3 cells, which is an epithelial ovarian cancer model, through PI3K/AKT/mTOR pathway."
NAD+PMID 31103405
"Docking simulation of compound 2 toward NAMPT using the crystal structure of the FK866-NAMPT complex (PDB code: 2GVJ) with replacing the boron atom type by the C3 atom type of carboranes predicted that the NAMPT inhibitory activity of 2c was improved by the hydrogen bond formation between the carborane amide and H191 of NAMPT."
autophagyPMID 34491140
"ATG7: autophagy related 7; BODIPY: boron dipyrromethene; DAG: diacyl glycerides; DBI: diazepam binding inhibitor; GFP: green fluorescent protein; KRT14: keratin 14; HPLC-MS: high performance liquid chromatography-mass spectrometry; LD: lipid droplet; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MSI: mass spectrometric imaging; ORO: Oil Red O; PC: phosphatidylcholine; PE:…"
mTORPMID 31944172
"This study shows that sustained high autophagic flux by RUBCN deficiency in PTECs leads to metabolic syndrome concomitantly with an accelerated mobilization of phospholipids from cellular membranes to lysosomes. <b>Abbreviations</b>: ABC: ATP binding cassette; ACADM: acyl-CoA dehydrogenase medium chain; ACTB: actin, beta; ATG: autophagy related; AUC: area under the curve; Baf: bafilomycin…"
autophagyPMID 31944172
"This study shows that sustained high autophagic flux by RUBCN deficiency in PTECs leads to metabolic syndrome concomitantly with an accelerated mobilization of phospholipids from cellular membranes to lysosomes. <b>Abbreviations</b>: ABC: ATP binding cassette; ACADM: acyl-CoA dehydrogenase medium chain; ACTB: actin, beta; ATG: autophagy related; AUC: area under the curve; Baf: bafilomycin…"
mTORPMID 32546086
"In conclusion, EPA counteracts lipotoxicity in the proximal tubule by alleviating autophagic numbness, making it potentially suitable as a novel treatment for obesity-related kidney diseases.<b>Abbreviations:</b> 4-HNE: 4-hydroxy-2-nonenal; ACTB: actin beta; ADGRE1/F4/80: adhesion G protein-coupled receptor E1; ATG: autophagy-related; ATP: adenosine triphosphate; BODIPY: boron-dipyrromethene;…"
1 more recorded row
autophagyPMID 32546086
"In conclusion, EPA counteracts lipotoxicity in the proximal tubule by alleviating autophagic numbness, making it potentially suitable as a novel treatment for obesity-related kidney diseases.<b>Abbreviations:</b> 4-HNE: 4-hydroxy-2-nonenal; ACTB: actin beta; ADGRE1/F4/80: adhesion G protein-coupled receptor E1; ATG: autophagy-related; ATP: adenosine triphosphate; BODIPY: boron-dipyrromethene;…"
recorded 2024-11-12 · last checked 2026-09-04
Where it is registeredIdentifiers, relations and other names
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
✗ required summary fields resolved: 4 required field(s) not terminal: Why people use it, Best-supported result, Biggest unanswered question, Human evidence
✓ public claims reviewed: 0 reviewed claim(s); drafts are never rendered
✓ source coverage passed: 8 source rows
✓ no critical contamination: no quarantine open
✓ canonical metadata passed: slug and display name present
✓ no raw internal fields: enforced by the copy-contract test over the rendered page
This is a record of evidence. It is not medical advice, and it does not say this substance suits you. Nothing here says any substance on RNAWiki is appropriate for a child.