Homocysteine
Reads: Homocysteine
The same Molecule Feeds Methylation or Antioxidant Defense, and b-vitamin Status Decides Which. Remethylation needs folate and B12; transsulfuration needs B6. That is why a single deficiency can present as either an epigenetic or a redox problem. Raised homocysteine is a marker of the fork being blocked, not a toxin in its own right — lowering it with vitamins has repeatedly failed to reproduce the outcome benefit its epidemiology predicted.
What this marker reads
The junction metabolite — remethylated back to methionine, or committed down transsulfuration to cysteine.
What a named body publishes
Each line below is the sentence the issuing body wrote, carried with its own identifier. Nothing here interprets your result — it states what was published, for whom, and by whom.
Homocysteine
“For adults aged 15-65 years in a folate-supplemented or folate-fortified population, the upper reference limit for fasting total homocysteine is 12 umol/L.” 15-65
Facts and Recommendations about Total Homocysteine Determinations: An Expert Opinion · Clinical Chemistry · 2004 DOI 10.1373/clinchem.2003.021634
“For adults aged 15-65 years in a non-supplemented, non-fortified population, the upper reference limit for fasting total homocysteine is 15 umol/L.” 15-65
Facts and Recommendations about Total Homocysteine Determinations: An Expert Opinion · Clinical Chemistry · 2004 DOI 10.1373/clinchem.2003.021634
“For people aged 65 years and over in a folate-supplemented or folate-fortified population, the upper reference limit for fasting total homocysteine is 16 umol/L.” 65 and over
Facts and Recommendations about Total Homocysteine Determinations: An Expert Opinion · Clinical Chemistry · 2004 DOI 10.1373/clinchem.2003.021634
“For people aged 65 years and over in a non-supplemented, non-fortified population, the upper reference limit for fasting total homocysteine is 20 umol/L.” 65 and over
Facts and Recommendations about Total Homocysteine Determinations: An Expert Opinion · Clinical Chemistry · 2004 DOI 10.1373/clinchem.2003.021634
“For children under 15 years in a folate-supplemented or folate-fortified population, the upper reference limit for fasting total homocysteine is 8 umol/L.” under 15
Facts and Recommendations about Total Homocysteine Determinations: An Expert Opinion · Clinical Chemistry · 2004 DOI 10.1373/clinchem.2003.021634
“For children under 15 years in a non-supplemented, non-fortified population, the upper reference limit for fasting total homocysteine is 10 umol/L.” under 15
Facts and Recommendations about Total Homocysteine Determinations: An Expert Opinion · Clinical Chemistry · 2004 DOI 10.1373/clinchem.2003.021634
“In pregnancy in a folate-supplemented or folate-fortified population, the upper reference limit for fasting total homocysteine is 8 umol/L.” females, pregnancy
Facts and Recommendations about Total Homocysteine Determinations: An Expert Opinion · Clinical Chemistry · 2004 DOI 10.1373/clinchem.2003.021634
“In pregnancy in a non-supplemented, non-fortified population, the upper reference limit for fasting total homocysteine is 10 umol/L.” females, pregnancy
Facts and Recommendations about Total Homocysteine Determinations: An Expert Opinion · Clinical Chemistry · 2004 DOI 10.1373/clinchem.2003.021634
Your laboratory reads your result against its own assay, and this page does not do that for it. What is above is what a named body published and for whom; the machinery this marker reads is set out on its pathway page, and the formulas witnessed on it are below.
The machinery behind it
What raises this marker and what it goes on to move — each edge carried with its own study — is set out in full on its pathway page: Homocysteine →
Formulas that modulate it
Each formula page names this pathway and carries the study behind its claim.
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