Oxalate

evidence_span

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experimental_model

MolyProbe live-cell FRET, MFSD5 overexpression and siRNA

exposure

Molybdate dose/time courses; 10 mM oxalate and 1 mM sulfate comparisons

limitations

High experimental concentration; does not establish dietary oxalate causing human molybdenum deficiency.

nutrient_topic

Molybdenum research collection; topical membership is not evidence of a direct dietary effect. · Molybdenum

organism

Homo sapiens

plain_language

High oxalate inhibited entry in this laboratory assay.

primary_references

[mo-p23472155] Exploring dynamics of molybdate in living animal cells by a genetically encoded FRET nanosensor. (2013). https://pubmed.ncbi.nlm.nih.gov/23472155/ DOI: 10.1371/journal.pone.0058175

tissue_or_cell_type

HEK-293T cells

Molybdenum: cofactor assembly, sulfur metabolism and nutrient interactions (2026-09-17) · lines 248–259

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · MolyProbe live-cell FRET, MFSD5 overexpression and siRNA · source_derived_draft · unverified_draft

### mo-oxalate-uptake Oxalate at 10 mM inhibited molybdate accumulation in HEK-293T cells. Condition category: normal nutrient_topic: Molybdenum research collection; topical membership is not evidence of a direct dietary effect. plain_language: High oxalate inhibited entry in this laboratory assay. organism: Homo sapiens tissue_or_cell_type: HEK-293T cells experimental_model: MolyProbe live-cell FRET, MFSD5 overexpression and siRNA limitations: High experimental concentration; does not establish dietary oxalate causing human molybdenum deficiency. exposure: Molybdate dose/time courses; 10 mM oxalate and 1 mM sulfate comparisons evidence_span: {"source_cache": "artifacts/molybdenum-research/23472155.fulltext.txt", "locator": "Exact primary full-text span; zero-based, end-exclusive Unicode character offsets", "file_sha256": "a3c76154f22db125e0e3c74c1dadbb32edae742411e28763ce2116dfd2e8202f", "start_char": 21554, "end_char": 22593, "text_sha256": "79bbaf42eff93e67e445d38383c53bbd3cea5b18c2e2afee38803b40f9b5fc4c"} [mo-p23472155] Exploring dynamics of molybdate in living animal cells by a genetically encoded FRET nanosensor. (2013). https://pubmed.ncbi.nlm.nih.gov/23472155/ DOI: 10.1371/journal.pone.0058175

experimental_model

Same short crossover experiment.

limitations

A saturation-related proxy is not an observed kidney-stone event or a universal prediction.

nutrient_topic

Calcium research collection; topical membership is not evidence of a direct dietary effect. · Calcium

organism

Homo sapiens

plain_language

The urinary crystallization proxy depended on timing.

primary_references

[cal-clin-domrong2004] Schedule of taking calcium supplement and the risk of nephrolithiasis (2004). https://pubmed.ncbi.nlm.nih.gov/15086924/ DOI: 10.1111/j.1523-1755.2004.00587.x

tissue_or_cell_type

Human clinical or absorption endpoint

Calcium: mechanism-first literature curation (2026-09-17) · lines 1270–1279

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Same short crossover experiment. · source_derived_draft · unverified_draft

### cal-bedtime-activity-product Urinary calcium-oxalate activity product increased after bedtime calcium carbonate but not after meal dosing. Condition category: normal nutrient_topic: Calcium research collection; topical membership is not evidence of a direct dietary effect. plain_language: The urinary crystallization proxy depended on timing. organism: Homo sapiens tissue_or_cell_type: Human clinical or absorption endpoint experimental_model: Same short crossover experiment. limitations: A saturation-related proxy is not an observed kidney-stone event or a universal prediction. [cal-clin-domrong2004] Schedule of taking calcium supplement and the risk of nephrolithiasis (2004). https://pubmed.ncbi.nlm.nih.gov/15086924/ DOI: 10.1111/j.1523-1755.2004.00587.x

experimental_model

Same randomized dietary trial.

limitations

Urine result supports a plausible intestinal explanation but does not isolate binding or prove mediation of recurrence.

nutrient_topic

Calcium research collection; topical membership is not evidence of a direct dietary effect. · Calcium

organism

Homo sapiens

plain_language

Diet composition changed urinary oxalate as well as calcium.

primary_references

[cal-clin-borghi2002] Comparison of two diets for the prevention of recurrent stones in idiopathic hypercalciuria (2002). https://pubmed.ncbi.nlm.nih.gov/11784873/ DOI: 10.1056/NEJMoa010369

tissue_or_cell_type

Human clinical or absorption endpoint

Calcium: mechanism-first literature curation (2026-09-17) · lines 1247–1256

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Same randomized dietary trial. · source_derived_draft · unverified_draft

### cal-borghi-urinary-oxalate Urinary oxalate rose with the low-calcium diet but fell with the normal-calcium, lower-protein, lower-salt diet. Condition category: normal nutrient_topic: Calcium research collection; topical membership is not evidence of a direct dietary effect. plain_language: Diet composition changed urinary oxalate as well as calcium. organism: Homo sapiens tissue_or_cell_type: Human clinical or absorption endpoint experimental_model: Same randomized dietary trial. limitations: Urine result supports a plausible intestinal explanation but does not isolate binding or prove mediation of recurrence. [cal-clin-borghi2002] Comparison of two diets for the prevention of recurrent stones in idiopathic hypercalciuria (2002). https://pubmed.ncbi.nlm.nih.gov/11784873/ DOI: 10.1056/NEJMoa010369

experimental_model

13-adult crossover; 200 mg calcium per test meal, double-isotope measurement.

exposure

Mean fractional absorption: spinach 5.1%, milk 27.6%; oxalate slightly exceeded calcium stoichiometrically in tested spinach.

limitations

Food-matrix comparison; oxalate binding was inferred from composition, not isolated experimentally. Not a comparison of every plant food.

nutrient_topic

Calcium research collection; topical membership is not evidence of a direct dietary effect. · Calcium

organism

Homo sapiens

plain_language

Equal calcium on a food label need not mean equal absorption.

primary_references

[cal-clin-heaney1988] Calcium absorbability from spinach (1988). https://pubmed.ncbi.nlm.nih.gov/3354496/ DOI: 10.1093/ajcn/47.4.707

tissue_or_cell_type

Human clinical or absorption endpoint

Calcium: mechanism-first literature curation (2026-09-17) · lines 1152–1162

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · 13-adult crossover; 200 mg calcium per test meal, double-isotope measurement. · source_derived_draft · unverified_draft

### cal-food-spinach-absorption Calcium absorption from the tested spinach meal was lower than from milk at equal calcium load. Condition category: normal nutrient_topic: Calcium research collection; topical membership is not evidence of a direct dietary effect. plain_language: Equal calcium on a food label need not mean equal absorption. organism: Homo sapiens tissue_or_cell_type: Human clinical or absorption endpoint experimental_model: 13-adult crossover; 200 mg calcium per test meal, double-isotope measurement. limitations: Food-matrix comparison; oxalate binding was inferred from composition, not isolated experimentally. Not a comparison of every plant food. exposure: Mean fractional absorption: spinach 5.1%, milk 27.6%; oxalate slightly exceeded calcium stoichiometrically in tested spinach. [cal-clin-heaney1988] Calcium absorbability from spinach (1988). https://pubmed.ncbi.nlm.nih.gov/3354496/ DOI: 10.1093/ajcn/47.4.707

experimental_model

32 healthy men, one-week crossover regimens.

exposure

1 g calcium carbonate with each of three meals versus 3 g carbonate at bedtime: compound mass, not 3 g elemental calcium.

limitations

This experiment measured urine, not long-term stone incidence.

nutrient_topic

Calcium research collection; topical membership is not evidence of a direct dietary effect. · Calcium

organism

Homo sapiens

plain_language

Taking the tested preparation with food changed oxalate handling.

primary_references

[cal-clin-domrong2004] Schedule of taking calcium supplement and the risk of nephrolithiasis (2004). https://pubmed.ncbi.nlm.nih.gov/15086924/ DOI: 10.1111/j.1523-1755.2004.00587.x

tissue_or_cell_type

Human clinical or absorption endpoint

Calcium: mechanism-first literature curation (2026-09-17) · lines 1258–1268

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · 32 healthy men, one-week crossover regimens. · source_derived_draft · unverified_draft

### cal-meal-urinary-oxalate Calcium carbonate with meals lowered urinary oxalate from baseline; bedtime dosing did not. Condition category: normal nutrient_topic: Calcium research collection; topical membership is not evidence of a direct dietary effect. plain_language: Taking the tested preparation with food changed oxalate handling. organism: Homo sapiens tissue_or_cell_type: Human clinical or absorption endpoint experimental_model: 32 healthy men, one-week crossover regimens. limitations: This experiment measured urine, not long-term stone incidence. exposure: 1 g calcium carbonate with each of three meals versus 3 g carbonate at bedtime: compound mass, not 3 g elemental calcium. [cal-clin-domrong2004] Schedule of taking calcium supplement and the risk of nephrolithiasis (2004). https://pubmed.ncbi.nlm.nih.gov/15086924/ DOI: 10.1111/j.1523-1755.2004.00587.x

availability_state

nutrient_deficiency Imported condition classification; unverified.

evidence_span

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experimental_model

Metabolic-ward feeding; 11 postmenopausal volunteers

exposure

167-day study; basal 0.36 mg B and 109 mg Mg/8400 kJ; 3 mg/day B supplement in last two 24-day periods; magnesium supplement 0 or 200 mg/day

limitations

Small study with multiple dietary periods and supplements. Do not assume independence from related reports from the same research program. Urine composition is not a kidney-stone clinical endpoint.

nutrient_topic

Boron research collection; topical membership is not evidence of a direct dietary effect. · Boron

organism

Human

plain_language

Less oxalate appeared in urine in this setting; fewer kidney stones were not demonstrated.

primary_references

[boron-p9062533] Metabolic responses of postmenopausal women to supplemental dietary boron and aluminum during usual and low magnesium intake: boron, calcium, and magnesium absorption and retention and blood mineral concentrations. (1997). https://pubmed.ncbi.nlm.nih.gov/9062533/ DOI: 10.1093/ajcn/65.3.803

tissue_or_cell_type

Mineral balance, blood and excreta

trigger_kind

nutrient_deficiency Imported condition classification; unverified.

Boron: chemistry, nutrient interactions, low-intake studies and mechanistic uncertainties (2026-09-17) · lines 677–688

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Metabolic-ward feeding; 11 postmenopausal volunteers · source_derived_draft · unverified_draft

### boron-oxalate-low-magnesium Boron supplementation decreased total urinary oxalate in the low-magnesium group. Condition category: nutrient_deficiency nutrient_topic: Boron research collection; topical membership is not evidence of a direct dietary effect. plain_language: Less oxalate appeared in urine in this setting; fewer kidney stones were not demonstrated. organism: Human tissue_or_cell_type: Mineral balance, blood and excreta experimental_model: Metabolic-ward feeding; 11 postmenopausal volunteers limitations: Small study with multiple dietary periods and supplements. Do not assume independence from related reports from the same research program. Urine composition is not a kidney-stone clinical endpoint. exposure: 167-day study; basal 0.36 mg B and 109 mg Mg/8400 kJ; 3 mg/day B supplement in last two 24-day periods; magnesium supplement 0 or 200 mg/day evidence_span: {"source_cache": "artifacts/boron-research/9062533.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "a23cd1fe09277bdd83b690746d4bbaf4742cdd74e51d5b27ee898bd87208b2be", "start_char": 0, "end_char": 1720, "text_sha256": "a23cd1fe09277bdd83b690746d4bbaf4742cdd74e51d5b27ee898bd87208b2be"} [boron-p9062533] Metabolic responses of postmenopausal women to supplemental dietary boron and aluminum during usual and low magnesium intake: boron, calcium, and magnesium absorption and retention and blood mineral concentrations. (1997). https://pubmed.ncbi.nlm.nih.gov/9062533/ DOI: 10.1093/ajcn/65.3.803

cross_nutrient

Calcium/oxalate urinary chemistry connects a vitamin metabolite to mineral precipitation risk.

experimental_model

Randomized controlled-diet crossover study: 29 calcium stone formers and 19 non-stone formers.

exposure

Ascorbic acid 1000 mg twice daily for six days versus no supplement for six days; 13C2 oxalate challenge after adaptation.

limitations

Calculated risk is not observed stone formation; this is distinct from a directly measured calcium oxalate activity product.

nutrient_topic

Vitamin C research collection; topical membership is not evidence of a direct dietary effect. · Vitamin C

organism

Homo sapiens

plain_language

Their urine measurements shifted toward a higher calculated calcium oxalate stone risk.

primary_references

[c-massey2005] Ascorbate increases human oxaluria and kidney stone risk (2005). https://pubmed.ncbi.nlm.nih.gov/15987848/ DOI: 10.1093/jn/135.7.1673

tissue_or_cell_type

Human blood or whole-person endpoints

Vitamin C: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 1682–1693

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Randomized controlled-diet crossover study: 29 calcium stone formers and 19 non-stone formers. · source_derived_draft · unverified_draft

### c-high-oral-dose-calcium-oxalate-index The responder subset had a Tiselius Risk Index of 1.10 with versus 0.76 without supplementation. Condition category: normal nutrient_topic: Vitamin C research collection; topical membership is not evidence of a direct dietary effect. plain_language: Their urine measurements shifted toward a higher calculated calcium oxalate stone risk. organism: Homo sapiens tissue_or_cell_type: Human blood or whole-person endpoints experimental_model: Randomized controlled-diet crossover study: 29 calcium stone formers and 19 non-stone formers. limitations: Calculated risk is not observed stone formation; this is distinct from a directly measured calcium oxalate activity product. exposure: Ascorbic acid 1000 mg twice daily for six days versus no supplement for six days; 13C2 oxalate challenge after adaptation. cross_nutrient: Calcium/oxalate urinary chemistry connects a vitamin metabolite to mineral precipitation risk. [c-massey2005] Ascorbate increases human oxaluria and kidney stone risk (2005). https://pubmed.ncbi.nlm.nih.gov/15987848/ DOI: 10.1093/jn/135.7.1673

experimental_model

Randomized controlled-diet crossover study: 29 calcium stone formers and 19 non-stone formers.

exposure

Ascorbic acid 1000 mg twice daily for six days versus no supplement for six days; 13C2 oxalate challenge after adaptation.

limitations

Not a universal effect in all 48 participants; intestinal mediator was not identified.

nutrient_topic

Vitamin C research collection; topical membership is not evidence of a direct dietary effect. · Vitamin C

organism

Homo sapiens

plain_language

The additional urinary oxalate was not attributed solely to vitamin C breakdown.

primary_references

[c-massey2005] Ascorbate increases human oxaluria and kidney stone risk (2005). https://pubmed.ncbi.nlm.nih.gov/15987848/ DOI: 10.1093/jn/135.7.1673

tissue_or_cell_type

Human blood or whole-person endpoints

Vitamin C: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 1670–1680

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Randomized controlled-diet crossover study: 29 calcium stone formers and 19 non-stone formers. · source_derived_draft · unverified_draft

### c-high-oral-dose-oxalate-absorption Responder-subset dietary oxalate absorption was 10.5% versus 8.0% with versus without vitamin C. Condition category: normal nutrient_topic: Vitamin C research collection; topical membership is not evidence of a direct dietary effect. plain_language: The additional urinary oxalate was not attributed solely to vitamin C breakdown. organism: Homo sapiens tissue_or_cell_type: Human blood or whole-person endpoints experimental_model: Randomized controlled-diet crossover study: 29 calcium stone formers and 19 non-stone formers. limitations: Not a universal effect in all 48 participants; intestinal mediator was not identified. exposure: Ascorbic acid 1000 mg twice daily for six days versus no supplement for six days; 13C2 oxalate challenge after adaptation. [c-massey2005] Ascorbate increases human oxaluria and kidney stone risk (2005). https://pubmed.ncbi.nlm.nih.gov/15987848/ DOI: 10.1093/jn/135.7.1673

experimental_model

Randomized controlled-diet crossover study: 29 calcium stone formers and 19 non-stone formers.

exposure

Ascorbic acid 1000 mg twice daily for six days versus no supplement for six days; 13C2 oxalate challenge after adaptation.

limitations

Selected subgroup and short exposure; does not identify every enzymatic or nonenzymatic conversion step.

nutrient_topic

Vitamin C research collection; topical membership is not evidence of a direct dietary effect. · Vitamin C

organism

Homo sapiens

plain_language

The tracer-based analysis separated oxalate made within the body from oxalate absorbed from the test diet.

primary_references

[c-massey2005] Ascorbate increases human oxaluria and kidney stone risk (2005). https://pubmed.ncbi.nlm.nih.gov/15987848/ DOI: 10.1093/jn/135.7.1673

tissue_or_cell_type

Human blood or whole-person endpoints

Vitamin C: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 1658–1668

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Randomized controlled-diet crossover study: 29 calcium stone formers and 19 non-stone formers. · source_derived_draft · unverified_draft

### c-high-oral-dose-oxalate-synthesis Within the responder subset, estimated endogenous oxalate synthesis was 544 versus 391 micromol/day with versus without supplementation. Condition category: normal nutrient_topic: Vitamin C research collection; topical membership is not evidence of a direct dietary effect. plain_language: The tracer-based analysis separated oxalate made within the body from oxalate absorbed from the test diet. organism: Homo sapiens tissue_or_cell_type: Human blood or whole-person endpoints experimental_model: Randomized controlled-diet crossover study: 29 calcium stone formers and 19 non-stone formers. limitations: Selected subgroup and short exposure; does not identify every enzymatic or nonenzymatic conversion step. exposure: Ascorbic acid 1000 mg twice daily for six days versus no supplement for six days; 13C2 oxalate challenge after adaptation. [c-massey2005] Ascorbate increases human oxaluria and kidney stone risk (2005). https://pubmed.ncbi.nlm.nih.gov/15987848/ DOI: 10.1093/jn/135.7.1673

cross_nutrient

Oxalate is relevant to calcium oxalate stone chemistry.

experimental_model

Randomized controlled-diet crossover study: 29 calcium stone formers and 19 non-stone formers.

exposure

Ascorbic acid 1000 mg twice daily for six days versus no supplement for six days; 13C2 oxalate challenge after adaptation.

limitations

Responders were defined by the observed rise; no incident-stone endpoint and no extrapolation to ordinary food intake.

nutrient_topic

Vitamin C research collection; topical membership is not evidence of a direct dietary effect. · Vitamin C

organism

Homo sapiens

plain_language

Some people excreted more oxalate after the high oral exposure.

primary_references

[c-massey2005] Ascorbate increases human oxaluria and kidney stone risk (2005). https://pubmed.ncbi.nlm.nih.gov/15987848/ DOI: 10.1093/jn/135.7.1673

tissue_or_cell_type

Human blood or whole-person endpoints

Vitamin C: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 1645–1656

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Randomized controlled-diet crossover study: 29 calcium stone formers and 19 non-stone formers. · source_derived_draft · unverified_draft

### c-high-oral-dose-oxaluria Nineteen of 48 participants, including 12 stone formers and seven non-stone formers, had more than 10% greater 24-hour oxalate excretion with 2 g/day vitamin C. Condition category: normal nutrient_topic: Vitamin C research collection; topical membership is not evidence of a direct dietary effect. plain_language: Some people excreted more oxalate after the high oral exposure. organism: Homo sapiens tissue_or_cell_type: Human blood or whole-person endpoints experimental_model: Randomized controlled-diet crossover study: 29 calcium stone formers and 19 non-stone formers. limitations: Responders were defined by the observed rise; no incident-stone endpoint and no extrapolation to ordinary food intake. exposure: Ascorbic acid 1000 mg twice daily for six days versus no supplement for six days; 13C2 oxalate challenge after adaptation. cross_nutrient: Oxalate is relevant to calcium oxalate stone chemistry. [c-massey2005] Ascorbate increases human oxaluria and kidney stone risk (2005). https://pubmed.ncbi.nlm.nih.gov/15987848/ DOI: 10.1093/jn/135.7.1673