Blood hemoglobin concentration

availability_state

nutrient_deficiency Imported condition classification; unverified.

cross_nutrient

B2 and iron supply can constrain different parts of erythropoiesis.

experimental_model

Controlled supplementation study in riboflavin-deficient Gambian men with hemoglobin below 11.5 g/dL; stable-isotope iron absorption.

exposure

Oral riboflavin versus no riboflavin; 3.38 mg 58Fe test dose before and after intervention; treatment dose not inferred from accessed abstract.

limitations

Controlled study in anemic deficient men; the specific marrow or mobilization mechanism was inferred, not directly established.

nutrient_topic

Riboflavin research collection; topical membership is not evidence of a direct dietary effect. · Riboflavin (vitamin B2)

organism

Homo sapiens

plain_language

Hemoglobin improved even though the measured storage marker stayed low.

primary_references

[b2-fairweather1992] Riboflavin deficiency and iron absorption in adult Gambian men (1992). https://pubmed.ncbi.nlm.nih.gov/1590670/ DOI: 10.1159/000177696

tissue_or_cell_type

Human clinical setting

trigger_kind

nutrient_deficiency Imported condition classification; unverified.

Riboflavin: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 1578–1589

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Controlled supplementation study in riboflavin-deficient Gambian men with hemoglobin below 11.5 g/dL; stable-isotope iron absorption. · source_derived_draft · unverified_draft

### b2-gambia-hemoglobin Riboflavin supplementation improved B2 status and hemoglobin in deficient Gambian men; low plasma ferritin did not change. Condition category: nutrient_deficiency nutrient_topic: Riboflavin research collection; topical membership is not evidence of a direct dietary effect. plain_language: Hemoglobin improved even though the measured storage marker stayed low. organism: Homo sapiens tissue_or_cell_type: Human clinical setting experimental_model: Controlled supplementation study in riboflavin-deficient Gambian men with hemoglobin below 11.5 g/dL; stable-isotope iron absorption. limitations: Controlled study in anemic deficient men; the specific marrow or mobilization mechanism was inferred, not directly established. exposure: Oral riboflavin versus no riboflavin; 3.38 mg 58Fe test dose before and after intervention; treatment dose not inferred from accessed abstract. cross_nutrient: B2 and iron supply can constrain different parts of erythropoiesis. [b2-fairweather1992] Riboflavin deficiency and iron absorption in adult Gambian men (1992). https://pubmed.ncbi.nlm.nih.gov/1590670/ DOI: 10.1159/000177696

cross_nutrient

Direct clinical comparison involving B2, vitamin A, iron and folic acid.

experimental_model

366 anemic pregnant women in rural China randomized among four groups for two months; all received iron and folic acid.

exposure

All arms: 60 mg/day iron plus 400 micrograms/day folic acid; added retinol 2000 micrograms/day, riboflavin 1 mg/day, both, or neither. Trial exposures, not recommendations.

limitations

Combination effect cannot be assigned solely to B2 or assumed to be biochemical synergy; anemic pregnant population, multiple co-deficiencies, two-month endpoint.

nutrient_topic

Riboflavin research collection; topical membership is not evidence of a direct dietary effect. · Riboflavin (vitamin B2)

organism

Homo sapiens

plain_language

Several nutrients were limiting in this population; the combination helped more than iron and folic acid alone.

primary_references

[b2-ma2008] Retinol and riboflavin supplementation decreases the prevalence of anemia in Chinese pregnant women taking iron and folic Acid supplements (2008). https://pubmed.ncbi.nlm.nih.gov/18806105/ DOI: 10.1093/jn/138.10.1946

tissue_or_cell_type

Human clinical setting

Riboflavin: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 1604–1615

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · 366 anemic pregnant women in rural China randomized among four groups for two months; all received iron and folic acid. · source_derived_draft · unverified_draft

### b2-pregnancy-multiple-nutrients Adding retinol and/or riboflavin to iron-folic-acid treatment reduced anemia prevalence more than iron-folic-acid alone; the combined retinol-riboflavin arm gained 5.4±1.1 g/L more hemoglobin than the reference arm. Condition category: normal nutrient_topic: Riboflavin research collection; topical membership is not evidence of a direct dietary effect. plain_language: Several nutrients were limiting in this population; the combination helped more than iron and folic acid alone. organism: Homo sapiens tissue_or_cell_type: Human clinical setting experimental_model: 366 anemic pregnant women in rural China randomized among four groups for two months; all received iron and folic acid. limitations: Combination effect cannot be assigned solely to B2 or assumed to be biochemical synergy; anemic pregnant population, multiple co-deficiencies, two-month endpoint. exposure: All arms: 60 mg/day iron plus 400 micrograms/day folic acid; added retinol 2000 micrograms/day, riboflavin 1 mg/day, both, or neither. Trial exposures, not recommendations. cross_nutrient: Direct clinical comparison involving B2, vitamin A, iron and folic acid. [b2-ma2008] Retinol and riboflavin supplementation decreases the prevalence of anemia in Chinese pregnant women taking iron and folic Acid supplements (2008). https://pubmed.ncbi.nlm.nih.gov/18806105/ DOI: 10.1093/jn/138.10.1946

availability_state

nutrient_deficiency Imported condition classification; unverified.

cross_nutrient

Riboflavin status modifies iron-related hematologic outcomes.

experimental_model

RIBOFEM: 123 UK women aged 19-25 randomized with EGRAC >1.40; 119 completed, 117 analyzed after two exclusions; iron-absorption subset 34.

exposure

Placebo, 2 or 4 mg/day riboflavin for eight weeks; historical trial regimens.

limitations

Baseline-tertile and response associations should not be restated as a uniform hemoglobin benefit in every randomized participant.

nutrient_topic

Riboflavin research collection; topical membership is not evidence of a direct dietary effect. · Riboflavin (vitamin B2)

organism

Homo sapiens

plain_language

Women with poorer starting B2 status tended to gain more hemoglobin when their B2 status improved.

primary_references

[b2-powers2011] Correcting a marginal riboflavin deficiency improves hematologic status in young women in the United Kingdom (RIBOFEM) (2011). https://pubmed.ncbi.nlm.nih.gov/21525198/ DOI: 10.3945/ajcn.110.008409

tissue_or_cell_type

Human clinical setting

trigger_kind

nutrient_deficiency Imported condition classification; unverified.

Riboflavin: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 1552–1563

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · RIBOFEM: 123 UK women aged 19-25 randomized with EGRAC >1.40; 119 completed, 117 analyzed after two exclusions; iron-absorption subset 34. · source_derived_draft · unverified_draft

### b2-ribofem-hemoglobin In RIBOFEM, improvement in B2 status correlated with hemoglobin increase among supplemented women; women with baseline EGRAC >1.65 had the greater hemoglobin response. Condition category: nutrient_deficiency nutrient_topic: Riboflavin research collection; topical membership is not evidence of a direct dietary effect. plain_language: Women with poorer starting B2 status tended to gain more hemoglobin when their B2 status improved. organism: Homo sapiens tissue_or_cell_type: Human clinical setting experimental_model: RIBOFEM: 123 UK women aged 19-25 randomized with EGRAC >1.40; 119 completed, 117 analyzed after two exclusions; iron-absorption subset 34. limitations: Baseline-tertile and response associations should not be restated as a uniform hemoglobin benefit in every randomized participant. exposure: Placebo, 2 or 4 mg/day riboflavin for eight weeks; historical trial regimens. cross_nutrient: Riboflavin status modifies iron-related hematologic outcomes. [b2-powers2011] Correcting a marginal riboflavin deficiency improves hematologic status in young women in the United Kingdom (RIBOFEM) (2011). https://pubmed.ncbi.nlm.nih.gov/21525198/ DOI: 10.3945/ajcn.110.008409

availability_state

nutrient_deficiency Imported condition classification; unverified.

cross_nutrient

Separates chemical absorption support from added clinical benefit during iron replacement.

experimental_model

Single-center open-label randomized equivalence trial: 440 adults with iron-deficiency anemia, 426 women.

exposure

Ferrous succinate 100 mg/tablet with or without vitamin C 200 mg every eight hours, three months; taken half an hour after meals. Tablet mass is not relabeled as elemental iron.

limitations

Equivalence is margin-dependent and does not mean numerical identity; no direct isotope absorption or intracellular mechanism was measured.

nutrient_topic

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

organism

Homo sapiens

plain_language

Adding vitamin C did not provide a clinically distinct early hemoglobin response under the trial’s equivalence definition.

primary_references

[c-li2020] The Efficacy and Safety of Vitamin C for Iron Supplementation in Adult Patients With Iron Deficiency Anemia: A Randomized Clinical Trial (2020). https://pubmed.ncbi.nlm.nih.gov/33136134/ DOI: 10.1001/jamanetworkopen.2020.23644

tissue_or_cell_type

Human blood or whole-person endpoints

trigger_kind

nutrient_deficiency Imported condition classification; unverified.

Vitamin C: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 1619–1630

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Single-center open-label randomized equivalence trial: 440 adults with iron-deficiency anemia, 426 women. · source_derived_draft · unverified_draft

### c-iron-treatment-hemoglobin-equivalence Hemoglobin increased 2.00 g/dL with iron plus C versus 1.84 with iron alone at two weeks; difference 0.16 (95% CI -0.03 to 0.35), within the prespecified 1-g/dL equivalence margin. Condition category: nutrient_deficiency nutrient_topic: Vitamin C research collection; topical membership is not evidence of a direct dietary effect. plain_language: Adding vitamin C did not provide a clinically distinct early hemoglobin response under the trial’s equivalence definition. organism: Homo sapiens tissue_or_cell_type: Human blood or whole-person endpoints experimental_model: Single-center open-label randomized equivalence trial: 440 adults with iron-deficiency anemia, 426 women. limitations: Equivalence is margin-dependent and does not mean numerical identity; no direct isotope absorption or intracellular mechanism was measured. exposure: Ferrous succinate 100 mg/tablet with or without vitamin C 200 mg every eight hours, three months; taken half an hour after meals. Tablet mass is not relabeled as elemental iron. cross_nutrient: Separates chemical absorption support from added clinical benefit during iron replacement. [c-li2020] The Efficacy and Safety of Vitamin C for Iron Supplementation in Adult Patients With Iron Deficiency Anemia: A Randomized Clinical Trial (2020). https://pubmed.ncbi.nlm.nih.gov/33136134/ DOI: 10.1001/jamanetworkopen.2020.23644

availability_state

nutrient_deficiency Imported condition classification; unverified.

cross_nutrient

Vitamin A/iron -> hemoglobin response.

experimental_model

Eight-week randomized trial.

limitations

Combined benefit does not prove a biochemical synergy or specify the cellular mediator.

nutrient_topic

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

organism

Homo sapiens

plain_language

Correcting more than one shortage improved the measured response in this population.

primary_references

[va-suharno1993] Supplementation with vitamin A and iron for nutritional anaemia in pregnant women in West Java, Indonesia (1993). https://pubmed.ncbi.nlm.nih.gov/7901636/ DOI: 10.1016/0140-6736(93)92246-p

tissue_or_cell_type

Blood

trigger_kind

nutrient_deficiency Imported condition classification; unverified.

Vitamin A: forms, mechanisms, deficiency and excess (2026-09-17) · lines 1448–1458

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

### va-iron-combined-hemoglobin Combined vitamin A and iron produced the largest hemoglobin response in the factorial pregnancy trial. Condition category: nutrient_deficiency nutrient_topic: Vitamin A research collection; topical membership is not evidence of a direct dietary effect. plain_language: Correcting more than one shortage improved the measured response in this population. organism: Homo sapiens tissue_or_cell_type: Blood experimental_model: Eight-week randomized trial. limitations: Combined benefit does not prove a biochemical synergy or specify the cellular mediator. cross_nutrient: Vitamin A/iron -> hemoglobin response. [va-suharno1993] Supplementation with vitamin A and iron for nutritional anaemia in pregnant women in West Java, Indonesia (1993). https://pubmed.ncbi.nlm.nih.gov/7901636/ DOI: 10.1016/0140-6736(93)92246-p

experimental_model

113 girls, randomized double-blind placebo-controlled trial.

exposure

500 mg calcium/day with evening meal for one year; reported marker comparisons were nonsignificant.

limitations

Does not establish absence of effect in iron-deficient people; hemoglobin, ferritin and soluble transferrin receptor are distinct endpoints.

nutrient_topic

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

organism

Homo sapiens

plain_language

No significant worsening of iron markers was found after a year of supplementation in these girls.

primary_references

[cal-clin-molgaard2005] Long-term calcium supplementation does not affect the iron status of 12-14-y-old girls (2005). https://pubmed.ncbi.nlm.nih.gov/16002806/ DOI: 10.1093/ajcn.82.1.98

tissue_or_cell_type

Human clinical or absorption endpoint

Calcium: mechanism-first literature curation (2026-09-17) · lines 1434–1444

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · 113 girls, randomized double-blind placebo-controlled trial. · source_derived_draft · unverified_draft

### cal-iron-status-longterm One year of calcium supplementation did not significantly alter measured iron-status markers in adolescent girls. Condition category: normal nutrient_topic: Calcium research collection; topical membership is not evidence of a direct dietary effect. plain_language: No significant worsening of iron markers was found after a year of supplementation in these girls. organism: Homo sapiens tissue_or_cell_type: Human clinical or absorption endpoint experimental_model: 113 girls, randomized double-blind placebo-controlled trial. limitations: Does not establish absence of effect in iron-deficient people; hemoglobin, ferritin and soluble transferrin receptor are distinct endpoints. exposure: 500 mg calcium/day with evening meal for one year; reported marker comparisons were nonsignificant. [cal-clin-molgaard2005] Long-term calcium supplementation does not affect the iron status of 12-14-y-old girls (2005). https://pubmed.ncbi.nlm.nih.gov/16002806/ DOI: 10.1093/ajcn.82.1.98

availability_state

nutrient_deficiency Imported condition classification; unverified.

cross_nutrient

Iron supply alone did not prevent anemia in the combined B2 restriction/antagonist experiment.

experimental_model

Historical induced-depletion study in six men with inoperable cancers; no healthy randomized control group.

exposure

Low-riboflavin semisynthetic diet plus galactoflavin antagonist, followed by riboflavin replacement; three also received oral antibiotics.

limitations

Same six-patient experiment as lesion record; other nutrients were supplied but cancer and antagonist effects limit causal generalization.

nutrient_topic

Riboflavin research collection; topical membership is not evidence of a direct dietary effect. · Riboflavin (vitamin B2)

organism

Homo sapiens

plain_language

Severe induced shortage reduced new red-cell production; the anemia was not simply assumed to be low dietary iron.

primary_references

[b2-lane1964] THE RAPID INDUCTION OF HUMAN RIBOFLAVIN DEFICIENCY WITH GALACTOFLAVIN (1964). https://pubmed.ncbi.nlm.nih.gov/14135487/ DOI: 10.1172/jci104921

tissue_or_cell_type

Bone marrow and circulating erythrocytes

trigger_kind

nutrient_deficiency Imported condition classification; unverified.

Riboflavin: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 1801–1812

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Historical induced-depletion study in six men with inoperable cancers; no healthy randomized control group. · source_derived_draft · unverified_draft

### b2-induced-erythroid-suppression All six patients developed anemia; the study described low reticulocytes and erythroid suppression with recovery during riboflavin replacement. Condition category: nutrient_deficiency nutrient_topic: Riboflavin research collection; topical membership is not evidence of a direct dietary effect. plain_language: Severe induced shortage reduced new red-cell production; the anemia was not simply assumed to be low dietary iron. organism: Homo sapiens tissue_or_cell_type: Bone marrow and circulating erythrocytes experimental_model: Historical induced-depletion study in six men with inoperable cancers; no healthy randomized control group. limitations: Same six-patient experiment as lesion record; other nutrients were supplied but cancer and antagonist effects limit causal generalization. exposure: Low-riboflavin semisynthetic diet plus galactoflavin antagonist, followed by riboflavin replacement; three also received oral antibiotics. cross_nutrient: Iron supply alone did not prevent anemia in the combined B2 restriction/antagonist experiment. [b2-lane1964] THE RAPID INDUCTION OF HUMAN RIBOFLAVIN DEFICIENCY WITH GALACTOFLAVIN (1964). https://pubmed.ncbi.nlm.nih.gov/14135487/ DOI: 10.1172/jci104921

cross_nutrient

Iron (coadministered_nutrient); Hematocrit (measured_endpoint); Blood hemoglobin concentration (unchanged_endpoint)

evidence_location

Indexed primary abstract.

evidence_span

{"source_cache": "artifacts/zinc-clinical-sources/yadrick1989.abstract.txt", "locator": "Primary indexed abstract; complete local file", "file_sha256": "e2d70d43dded75edb026cac237f238d9e59399db6094098796e169f20e819443", "utf8_bytes": 969}

experimental_model

Ten-week zinc or zinc-plus-iron intervention in adult women

exposure

50 mg elemental zinc/day as gluconate, with or without 50 mg iron/day as ferrous sulfate monohydrate.

limitations

Reported comparisons are within-group pretreatment versus 10 weeks, not placebo-adjusted effects. ESOD is a functional biomarker, not a diagnosis of symptomatic copper deficiency.

nutrient_topic

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

organism

Homo sapiens

plain_language

Iron-status markers responded differently depending on whether iron accompanied zinc.

primary_references

[zn-clin-yadrick1989] Iron, copper, and zinc status: response to supplementation with zinc or zinc and iron in adult females. (1989). https://pubmed.ncbi.nlm.nih.gov/2912000/ DOI: 10.1093/ajcn/49.1.145

tissue_or_cell_type

Blood and erythrocytes

Zinc: transport, enzyme loading, deficiency and nutrient interactions (2026-09-17) · lines 1196–1209

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Ten-week zinc or zinc-plus-iron intervention in adult women · source_derived_draft · unverified_draft

### zn-clin-iron-markers Zinc-only treatment was followed by lower serum ferritin and hematocrit; with added iron, ferritin increased and hematocrit was unchanged. Hemoglobin did not change in either group. Condition category: normal nutrient_topic: Zinc research collection; topical membership is not evidence of a direct dietary effect. plain_language: Iron-status markers responded differently depending on whether iron accompanied zinc. organism: Homo sapiens tissue_or_cell_type: Blood and erythrocytes experimental_model: Ten-week zinc or zinc-plus-iron intervention in adult women limitations: Reported comparisons are within-group pretreatment versus 10 weeks, not placebo-adjusted effects. ESOD is a functional biomarker, not a diagnosis of symptomatic copper deficiency. exposure: 50 mg elemental zinc/day as gluconate, with or without 50 mg iron/day as ferrous sulfate monohydrate. cross_nutrient: Iron (coadministered_nutrient); Hematocrit (measured_endpoint); Blood hemoglobin concentration (unchanged_endpoint) evidence_location: Indexed primary abstract. evidence_span: {"source_cache": "artifacts/zinc-clinical-sources/yadrick1989.abstract.txt", "locator": "Primary indexed abstract; complete local file", "file_sha256": "e2d70d43dded75edb026cac237f238d9e59399db6094098796e169f20e819443", "utf8_bytes": 969} [zn-clin-yadrick1989] Iron, copper, and zinc status: response to supplementation with zinc or zinc and iron in adult females. (1989). https://pubmed.ncbi.nlm.nih.gov/2912000/ DOI: 10.1093/ajcn/49.1.145

availability_state

nutrient_deficiency Imported condition classification; unverified.

cross_nutrient

Vitamin A -> EPO/iron use.

experimental_model

Randomized ten-month follow-up.

limitations

EPO was measured, not blocked; its mediation of the hemoglobin response remains inferred.

nutrient_topic

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

organism

Homo sapiens

plain_language

Vitamin A can influence the signal that supports red-cell production.

primary_references

[va-zimmermann2006-iron] Vitamin A supplementation in children with poor vitamin A and iron status increases erythropoietin and hemoglobin concentrations without changing total body iron (2006). https://pubmed.ncbi.nlm.nih.gov/16960172/ DOI: 10.1093/ajcn/84.3.580

tissue_or_cell_type

Blood

trigger_kind

nutrient_deficiency Imported condition classification; unverified.

Vitamin A: forms, mechanisms, deficiency and excess (2026-09-17) · lines 1460–1470

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Randomized ten-month follow-up. · source_derived_draft · unverified_draft

### va-repletion-erythropoietin Vitamin A increased circulating EPO and hemoglobin in schoolchildren with poor nutrient status. Condition category: nutrient_deficiency nutrient_topic: Vitamin A research collection; topical membership is not evidence of a direct dietary effect. plain_language: Vitamin A can influence the signal that supports red-cell production. organism: Homo sapiens tissue_or_cell_type: Blood experimental_model: Randomized ten-month follow-up. limitations: EPO was measured, not blocked; its mediation of the hemoglobin response remains inferred. cross_nutrient: Vitamin A -> EPO/iron use. [va-zimmermann2006-iron] Vitamin A supplementation in children with poor vitamin A and iron status increases erythropoietin and hemoglobin concentrations without changing total body iron (2006). https://pubmed.ncbi.nlm.nih.gov/16960172/ DOI: 10.1093/ajcn/84.3.580