Homocysteine: normal range and what it means
An amino acid that, when high, raises cardiovascular and cognitive risk.
Normal range
Adult reference range.
- Optimal< 10 µmol/L
- Borderline10 – 15 µmol/L
- High≥ 15 µmol/L
What it measures
An amino acid cleared with the help of B-vitamins. High levels are associated with heart and brain risk.
What moves it
B12, folate and B6 status, kidney function, and genetics (MTHFR).
How to bring it into range
Adequate B12, folate and B6 — often the main fix.
How fast it responds
Weeks.
Also reported as: hcy
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Common questions
- What is a normal Homocysteine level?
- Optimal: < 10 µmol/L. Adult reference range.
- What does a high Homocysteine mean?
- A value above the reference band means Homocysteine is outside the range typical for a healthy adult. A single reading is rarely conclusive on its own — what matters is the trend across draws and the other markers around it, which is why HealthOS reads the whole panel together rather than one number at a time.
- How do I improve my Homocysteine?
- Adequate B12, folate and B6 — often the main fix.
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Reference ranges are general-population guidance compiled from common clinical laboratories, not a diagnosis. Lab-to-lab ranges differ. Always read your results with your doctor.