Component
Human urinary 3-hydroxyisovaleric acid excretion
Human urinary 3-hydroxyisovaleric acid excretion. Species, exposure and limitations are retained in each linked claim.
4 recorded relationships. Experimental role, claim status and evidence remain attached to each record.
How nutrients influence it
Every nutrient with a recorded effect on this component, credited to the nutrient that acted rather than the chapter that recorded it. Open a nutrient to see the findings and the conditions they were measured under.
Other things that act on it
Enzymes, hormones, genes, and other components with a recorded effect. These are not nutrients, so they do not count toward the arrows above. Each finding names the chapter that recorded it.
How nutrients reach it in more than one step
Chains of two or more recorded steps that end here, grouped by the nutrient they start from. Each step is a separate finding, so a chain is a route a mechanism could take, not proof that it does.
Tracing routes…
What it does
Every recorded relationship this component is part of, grouped by its role. Plain wording comes first; the technical statement follows.
What acts on it
Urinary 3-HIA increased during 28-day biotin depletion in 11 adults; biotin-status indicators normalized in most after one week on a general diet.
Experimental context and source evidence
- availability_state
- nutrient_deficiency Imported condition classification; unverified.
- evidence_span
- {"source_cache": "artifacts/biotin-research/12399279.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "38158dd10cfc6528b65a3304fac58a5b5d8ec82e20673534b5bf6e9e79f14b09", "start_char": 0, "end_char": 1718, "text_sha256": "38158dd10cfc6528b65a3304fac58a5b5d8ec82e20673534b5bf6e9e79f14b09"}
- experimental_model
- Experimental depletion/repletion in 11 healthy adults; leucine challenge in 5
- exposure
- 28 days of egg-white diet followed by general diet with or without 80 micrograms supplemental biotin
- limitations
- An intentional undenatured egg-white diet is not ordinary cooked-egg intake. Small experimental cohorts do not establish a population-wide threshold.
- nutrient_topic
- Biotin research collection; topical membership is not evidence of a direct dietary effect. · Biotin
- organism
- Homo sapiens
- plain_language
- A bottleneck in leucine breakdown became measurable before a universal clinical syndrome was required.
- primary_references
- [b7-p12399279] Indicators of marginal biotin deficiency and repletion in humans: validation of 3-hydroxyisovaleric acid excretion and a leucine challenge. (2002). https://pubmed.ncbi.nlm.nih.gov/12399279/ DOI: 10.1093/ajcn/76.5.1061
- tissue_or_cell_type
- Dietary exposure and urinary metabolites
- trigger_kind
- nutrient_deficiency Imported condition classification; unverified.
Biotin: carboxylases, recycling, deficiency and nutrient interactions (2026-09-17) · lines 897–908
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Experimental depletion/repletion in 11 healthy adults; leucine challenge in 5 · source_derived_draft · unverified_draft
### b7-depletion-3hia Urinary 3-HIA increased during 28-day biotin depletion in 11 adults; biotin-status indicators normalized in most after one week on a general diet. Condition category: nutrient_deficiency nutrient_topic: Biotin research collection; topical membership is not evidence of a direct dietary effect. plain_language: A bottleneck in leucine breakdown became measurable before a universal clinical syndrome was required. organism: Homo sapiens tissue_or_cell_type: Dietary exposure and urinary metabolites experimental_model: Experimental depletion/repletion in 11 healthy adults; leucine challenge in 5 limitations: An intentional undenatured egg-white diet is not ordinary cooked-egg intake. Small experimental cohorts do not establish a population-wide threshold. exposure: 28 days of egg-white diet followed by general diet with or without 80 micrograms supplemental biotin evidence_span: {"source_cache": "artifacts/biotin-research/12399279.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "38158dd10cfc6528b65a3304fac58a5b5d8ec82e20673534b5bf6e9e79f14b09", "start_char": 0, "end_char": 1718, "text_sha256": "38158dd10cfc6528b65a3304fac58a5b5d8ec82e20673534b5bf6e9e79f14b09"} [b7-p12399279] Indicators of marginal biotin deficiency and repletion in humans: validation of 3-hydroxyisovaleric acid excretion and a leucine challenge. (2002). https://pubmed.ncbi.nlm.nih.gov/12399279/ DOI: 10.1093/ajcn/76.5.1061
Complete structured claim and evidenceThe carbamazepine/phenytoin group had higher urinary 3-HIA, but only one child in that group had low urinary biotin.
Experimental context and source evidence
- availability_state
- biomarker_context Imported condition classification; unverified.
- evidence_span
- {"source_cache": "artifacts/biotin-research/9523856.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "a337d853fbf3d26e053dfd6d17b2e1729c993a0501563d0524ebbee7b44d5136", "start_char": 0, "end_char": 1876, "text_sha256": "a337d853fbf3d26e053dfd6d17b2e1729c993a0501563d0524ebbee7b44d5136"}
- experimental_model
- Observational urine comparison: 7 children receiving carbamazepine/phenytoin, 6 phenobarbital, 16 controls
- exposure
- Long-term anticonvulsant treatment
- limitations
- Untimed urine, small nonrandomized groups and discordant markers limit diagnosis; faster turnover is not a universal deficiency diagnosis.
- nutrient_topic
- Biotin research collection; topical membership is not evidence of a direct dietary effect. · Biotin
- organism
- Homo sapiens
- plain_language
- Different biotin-status markers did not give the same answer in these children.
- primary_references
- [b7-p9523856] Disturbances in biotin metabolism in children undergoing long-term anticonvulsant therapy. (1998). https://pubmed.ncbi.nlm.nih.gov/9523856/ DOI: 10.1097/00005176-199803000-00002
- tissue_or_cell_type
- Urine
- trigger_kind
- biomarker_context Imported condition classification; unverified.
Biotin: carboxylases, recycling, deficiency and nutrient interactions (2026-09-17) · lines 312–323
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Observational urine comparison: 7 children receiving carbamazepine/phenytoin, 6 phenobarbital, 16 controls · source_derived_draft · unverified_draft
### b7-drug-3hia The carbamazepine/phenytoin group had higher urinary 3-HIA, but only one child in that group had low urinary biotin. Condition category: biomarker_context nutrient_topic: Biotin research collection; topical membership is not evidence of a direct dietary effect. plain_language: Different biotin-status markers did not give the same answer in these children. organism: Homo sapiens tissue_or_cell_type: Urine experimental_model: Observational urine comparison: 7 children receiving carbamazepine/phenytoin, 6 phenobarbital, 16 controls limitations: Untimed urine, small nonrandomized groups and discordant markers limit diagnosis; faster turnover is not a universal deficiency diagnosis. exposure: Long-term anticonvulsant treatment evidence_span: {"source_cache": "artifacts/biotin-research/9523856.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "a337d853fbf3d26e053dfd6d17b2e1729c993a0501563d0524ebbee7b44d5136", "start_char": 0, "end_char": 1876, "text_sha256": "a337d853fbf3d26e053dfd6d17b2e1729c993a0501563d0524ebbee7b44d5136"} [b7-p9523856] Disturbances in biotin metabolism in children undergoing long-term anticonvulsant therapy. (1998). https://pubmed.ncbi.nlm.nih.gov/9523856/ DOI: 10.1097/00005176-199803000-00002
Complete structured claim and evidenceChallenge-induced urinary 3-HIA rose more than twofold by day 14 in both biotin-depleted cohorts.
Experimental context and source evidence
- availability_state
- nutrient_deficiency Imported condition classification; unverified.
- evidence_span
- {"source_cache": "artifacts/biotin-research/21918059.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "5cf1d7e25ae7bdfeb2ac3225cee8e4e660723d5197fc057f63327b3ad9eb3aaf", "start_char": 0, "end_char": 1723, "text_sha256": "5cf1d7e25ae7bdfeb2ac3225cee8e4e660723d5197fc057f63327b3ad9eb3aaf"}
- experimental_model
- Leucine challenge during biotin depletion in two cohorts of 5 and 7 healthy adults
- exposure
- 28-day egg-white depletion; weekly oral leucine challenge
- limitations
- The challenge was sensitive but not diagnostically superior to 24-hour urine measurements; no validated universal threshold follows.
- nutrient_topic
- Biotin research collection; topical membership is not evidence of a direct dietary effect. · Biotin
- organism
- Homo sapiens
- plain_language
- Extra leucine made the impaired pathway easier to observe.
- primary_references
- [b7-p21918059] Urinary excretion of 3-hydroxyisovaleric acid and 3-hydroxyisovaleryl carnitine increases in response to a leucine challenge in marginally biotin-deficient humans. (2011). https://pubmed.ncbi.nlm.nih.gov/21918059/ DOI: 10.3945/jn.111.146126
- tissue_or_cell_type
- Urine
- trigger_kind
- nutrient_deficiency Imported condition classification; unverified.
Biotin: carboxylases, recycling, deficiency and nutrient interactions (2026-09-17) · lines 910–921
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Leucine challenge during biotin depletion in two cohorts of 5 and 7 healthy adults · source_derived_draft · unverified_draft
### b7-leucine-challenge-3hia Challenge-induced urinary 3-HIA rose more than twofold by day 14 in both biotin-depleted cohorts. Condition category: nutrient_deficiency nutrient_topic: Biotin research collection; topical membership is not evidence of a direct dietary effect. plain_language: Extra leucine made the impaired pathway easier to observe. organism: Homo sapiens tissue_or_cell_type: Urine experimental_model: Leucine challenge during biotin depletion in two cohorts of 5 and 7 healthy adults limitations: The challenge was sensitive but not diagnostically superior to 24-hour urine measurements; no validated universal threshold follows. exposure: 28-day egg-white depletion; weekly oral leucine challenge evidence_span: {"source_cache": "artifacts/biotin-research/21918059.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "5cf1d7e25ae7bdfeb2ac3225cee8e4e660723d5197fc057f63327b3ad9eb3aaf", "start_char": 0, "end_char": 1723, "text_sha256": "5cf1d7e25ae7bdfeb2ac3225cee8e4e660723d5197fc057f63327b3ad9eb3aaf"} [b7-p21918059] Urinary excretion of 3-hydroxyisovaleric acid and 3-hydroxyisovaleryl carnitine increases in response to a leucine challenge in marginally biotin-deficient humans. (2011). https://pubmed.ncbi.nlm.nih.gov/21918059/ DOI: 10.3945/jn.111.146126
Complete structured claim and evidenceAt the controlled intake, pregnant women excreted 69% more 3-HIA than controls, while urinary 3-HIA-carnitine was 27% lower.
Experimental context and source evidence
- availability_state
- biomarker_context Imported condition classification; unverified.
- evidence_span
- {"source_cache": "artifacts/biotin-research/25122647.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "6066b007a013c3c0c69336e7aba0e51baa39e3a24b6eb918cb4778e792376a9b", "start_char": 0, "end_char": 2354, "text_sha256": "6066b007a013c3c0c69336e7aba0e51baa39e3a24b6eb918cb4778e792376a9b"}
- experimental_model
- Controlled feeding: 26 pregnant, 28 lactating and 21 control women
- exposure
- 57 micrograms dietary biotin per day for 10–12 weeks
- limitations
- Groups differed in reproductive state. Marker changes do not establish fetal outcomes, universal deficiency or a treatment dose.
- nutrient_topic
- Biotin research collection; topical membership is not evidence of a direct dietary effect. · Biotin
- organism
- Homo sapiens
- plain_language
- Two related markers moved in opposite directions during pregnancy.
- primary_references
- [b7-p25122647] Pregnancy and lactation alter biomarkers of biotin metabolism in women consuming a controlled diet. (2014). https://pubmed.ncbi.nlm.nih.gov/25122647/ DOI: 10.3945/jn.114.194472
- tissue_or_cell_type
- Urine and plasma
- trigger_kind
- biomarker_context Imported condition classification; unverified.
Biotin: carboxylases, recycling, deficiency and nutrient interactions (2026-09-17) · lines 988–999
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Controlled feeding: 26 pregnant, 28 lactating and 21 control women · source_derived_draft · unverified_draft
### b7-pregnancy-3hia At the controlled intake, pregnant women excreted 69% more 3-HIA than controls, while urinary 3-HIA-carnitine was 27% lower. Condition category: biomarker_context nutrient_topic: Biotin research collection; topical membership is not evidence of a direct dietary effect. plain_language: Two related markers moved in opposite directions during pregnancy. organism: Homo sapiens tissue_or_cell_type: Urine and plasma experimental_model: Controlled feeding: 26 pregnant, 28 lactating and 21 control women limitations: Groups differed in reproductive state. Marker changes do not establish fetal outcomes, universal deficiency or a treatment dose. exposure: 57 micrograms dietary biotin per day for 10–12 weeks evidence_span: {"source_cache": "artifacts/biotin-research/25122647.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "6066b007a013c3c0c69336e7aba0e51baa39e3a24b6eb918cb4778e792376a9b", "start_char": 0, "end_char": 2354, "text_sha256": "6066b007a013c3c0c69336e7aba0e51baa39e3a24b6eb918cb4778e792376a9b"} [b7-p25122647] Pregnancy and lactation alter biomarkers of biotin metabolism in women consuming a controlled diet. (2014). https://pubmed.ncbi.nlm.nih.gov/25122647/ DOI: 10.3945/jn.114.194472
Complete structured claim and evidence
The events it takes part in
A mechanism often involves more than two components. These are the full events, with every participant and its role.
Situations it appears in
Low-supply and faulty-machinery situations recorded in the chapters where this component plays a part.
In the sources
Preserved passages that mention this component, quoted exactly. Open one to read it in context.
Open hypotheses
Proposed ideas that involve this component. They are labeled as hypotheses and do not change any recorded statement.
This is a research prototype built from draft material. It is not medical advice, and its statements still await verification against the original studies.