Component

Human fasting plasma total homocysteine concentration

Human fasting plasma total homocysteine concentration. Species, exposure and limitations are retained in each linked claim.

3 recorded relationships. Experimental role, claim status and evidence remain attached to each record.

Read recorded mechanisms Open recursive mind map

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.

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.

Recorded relationships

What acts on it

  1. Two weeks of phosphatidylcholine supplementation reduced fasting total homocysteine by 18% relative to placebo.

    Study-specific phosphatidylcholine supplements → Human fasting plasma total homocysteine concentration source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/choline-research/16002808.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "ad206000c96c52d280ac135c03d531122121a82c436dce40c7d13e55d0976ae1", "start_char": 0, "end_char": 1797, "text_sha256": "ad206000c96c52d280ac135c03d531122121a82c436dce40c7d13e55d0976ae1"}
    experimental_model
    Randomized crossover feeding trial
    exposure
    About 2.6 g choline/day as PC versus matched placebo oil for two weeks; methionine-load testing
    limitations
    High experimental intake and biomarker endpoint; no cardiovascular-event benefit was tested.
    nutrient_topic
    Choline research collection; topical membership is not evidence of a direct dietary effect. · Choline
    organism
    Human
    plain_language
    A choline-containing form changed a methyl-metabolism blood marker.
    primary_references
    [choline-p16002808] Choline supplemented as phosphatidylcholine decreases fasting and postmethionine-loading plasma homocysteine concentrations in healthy men. (2005). https://pubmed.ncbi.nlm.nih.gov/16002808/ DOI: 10.1093/ajcn.82.1.111
    tissue_or_cell_type
    26 men with mildly elevated plasma homocysteine

    Choline: metabolism, signaling and nutrient connections (2026-09-17) · lines 1075–1086

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

    ### choline-pc-hcy-fasting Two weeks of phosphatidylcholine supplementation reduced fasting total homocysteine by 18% relative to placebo. Condition category: normal nutrient_topic: Choline research collection; topical membership is not evidence of a direct dietary effect. plain_language: A choline-containing form changed a methyl-metabolism blood marker. organism: Human tissue_or_cell_type: 26 men with mildly elevated plasma homocysteine experimental_model: Randomized crossover feeding trial limitations: High experimental intake and biomarker endpoint; no cardiovascular-event benefit was tested. exposure: About 2.6 g choline/day as PC versus matched placebo oil for two weeks; methionine-load testing evidence_span: {"source_cache": "artifacts/choline-research/16002808.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "ad206000c96c52d280ac135c03d531122121a82c436dce40c7d13e55d0976ae1", "start_char": 0, "end_char": 1797, "text_sha256": "ad206000c96c52d280ac135c03d531122121a82c436dce40c7d13e55d0976ae1"} [choline-p16002808] Choline supplemented as phosphatidylcholine decreases fasting and postmethionine-loading plasma homocysteine concentrations in healthy men. (2005). https://pubmed.ncbi.nlm.nih.gov/16002808/ DOI: 10.1093/ajcn.82.1.111
    Complete structured claim and evidence

  2. Patients with vitamin B-12 deficiency at study end had a mean homocysteine of 23.7 micromol/l, compared with 18.1 in those with low B-12 and 14.9 in those with normal B-12.

    Serum cobalamin concentration → Human fasting plasma total homocysteine concentration source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    biomarker_context Imported condition classification; unverified.
    evidence_span
    {"source_cache": "artifacts/metformin-research/20488910.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "6c9e09d44fe1103e6927321e925e69e31c38d1a688fd2ac18ea96927098de922", "start_char": 0, "end_char": 2518, "text_sha256": "6c9e09d44fe1103e6927321e925e69e31c38d1a688fd2ac18ea96927098de922"}
    experimental_model
    Multicentre randomised placebo-controlled trial, 390 people with type 2 diabetes on insulin
    exposure
    850 mg metformin three times daily for 4.3 years versus placebo
    limitations
    The strongest available human causal evidence for the B12 effect. It measured concentrations and deficiency incidence, not clinical deficiency syndromes.
    nutrient_topic
    Metformin research collection; topical membership is not evidence of a direct clinical effect, and pharmacological exposure is not dietary intake. · Metformin
    organism
    Human
    plain_language
    The lower the vitamin, the higher this metabolite climbed.
    primary_references
    [metformin-p20488910] Long term treatment with metformin in patients with type 2 diabetes and risk of vitamin B-12 deficiency: randomised placebo controlled trial. (2010). https://pubmed.ncbi.nlm.nih.gov/20488910/ DOI: 10.1136/bmj.c2181
    tissue_or_cell_type
    Whole body
    trigger_kind
    biomarker_context Imported condition classification; unverified.

    Metformin: transport, molecular targets, gut mechanisms and nutrient interactions (2026-09-19) · lines 1074–1085

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Multicentre randomised placebo-controlled trial, 390 people with type 2 diabetes on insulin · source_derived_draft · unverified_draft

    ### metformin-b12-homocysteine Patients with vitamin B-12 deficiency at study end had a mean homocysteine of 23.7 micromol/l, compared with 18.1 in those with low B-12 and 14.9 in those with normal B-12. Condition category: biomarker_context nutrient_topic: Metformin research collection; topical membership is not evidence of a direct clinical effect, and pharmacological exposure is not dietary intake. plain_language: The lower the vitamin, the higher this metabolite climbed. organism: Human tissue_or_cell_type: Whole body experimental_model: Multicentre randomised placebo-controlled trial, 390 people with type 2 diabetes on insulin limitations: The strongest available human causal evidence for the B12 effect. It measured concentrations and deficiency incidence, not clinical deficiency syndromes. exposure: 850 mg metformin three times daily for 4.3 years versus placebo evidence_span: {"source_cache": "artifacts/metformin-research/20488910.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "6c9e09d44fe1103e6927321e925e69e31c38d1a688fd2ac18ea96927098de922", "start_char": 0, "end_char": 2518, "text_sha256": "6c9e09d44fe1103e6927321e925e69e31c38d1a688fd2ac18ea96927098de922"} [metformin-p20488910] Long term treatment with metformin in patients with type 2 diabetes and risk of vitamin B-12 deficiency: randomised placebo controlled trial. (2010). https://pubmed.ncbi.nlm.nih.gov/20488910/ DOI: 10.1136/bmj.c2181
    Complete structured claim and evidence

  3. Metformin use was associated with a 4% increase in homocysteine, and the increase could be explained by the decreases in folate and vitamin B12.

    Metformin → Human fasting plasma total homocysteine concentration source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    biomarker_context Imported condition classification; unverified.
    evidence_span
    {"source_cache": "artifacts/metformin-research/14535967.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "ef4341dbaf004103ac5bc1df34e7286abd679d4b7a072c26655550135221123a", "start_char": 0, "end_char": 1640, "text_sha256": "ef4341dbaf004103ac5bc1df34e7286abd679d4b7a072c26655550135221123a"}
    experimental_model
    Placebo-controlled randomised trial of 390 people with type 2 diabetes over 16 weeks
    exposure
    Metformin added to insulin for 16 weeks versus placebo
    limitations
    Short-duration randomised evidence that the folate and B12 changes precede a measurable homocysteine change.
    nutrient_topic
    Metformin research collection; topical membership is not evidence of a direct clinical effect, and pharmacological exposure is not dietary intake. · Metformin
    organism
    Human
    plain_language
    The rise in that metabolite was accounted for by the two vitamins falling.
    primary_references
    [metformin-p14535967] Effects of short-term treatment with metformin on serum concentrations of homocysteine, folate and vitamin B12 in type 2 diabetes mellitus: a randomized, placebo-controlled trial. (2003). https://pubmed.ncbi.nlm.nih.gov/14535967/ DOI: 10.1046/j.1365-2796.2003.01213.x
    tissue_or_cell_type
    Whole body
    trigger_kind
    biomarker_context Imported condition classification; unverified.

    Metformin: transport, molecular targets, gut mechanisms and nutrient interactions (2026-09-19) · lines 1191–1202

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Placebo-controlled randomised trial of 390 people with type 2 diabetes over 16 weeks · source_derived_draft · unverified_draft

    ### metformin-short-term-homocysteine Metformin use was associated with a 4% increase in homocysteine, and the increase could be explained by the decreases in folate and vitamin B12. Condition category: biomarker_context nutrient_topic: Metformin research collection; topical membership is not evidence of a direct clinical effect, and pharmacological exposure is not dietary intake. plain_language: The rise in that metabolite was accounted for by the two vitamins falling. organism: Human tissue_or_cell_type: Whole body experimental_model: Placebo-controlled randomised trial of 390 people with type 2 diabetes over 16 weeks limitations: Short-duration randomised evidence that the folate and B12 changes precede a measurable homocysteine change. exposure: Metformin added to insulin for 16 weeks versus placebo evidence_span: {"source_cache": "artifacts/metformin-research/14535967.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "ef4341dbaf004103ac5bc1df34e7286abd679d4b7a072c26655550135221123a", "start_char": 0, "end_char": 1640, "text_sha256": "ef4341dbaf004103ac5bc1df34e7286abd679d4b7a072c26655550135221123a"} [metformin-p14535967] Effects of short-term treatment with metformin on serum concentrations of homocysteine, folate and vitamin B12 in type 2 diabetes mellitus: a randomized, placebo-controlled trial. (2003). https://pubmed.ncbi.nlm.nih.gov/14535967/ DOI: 10.1046/j.1365-2796.2003.01213.x
    Complete structured claim and evidence

In the sources

Preserved passages that mention this component, quoted exactly. Open one to read it in context.

    This is a research prototype built from draft material. It is not medical advice, and its statements still await verification against the original studies.

    Evidence, AI assistance and curation standards