In brief
Measures homocysteine, an amino acid. It is most often used to assess vitamin B12, folate and B6 levels.
What it measures
Homocysteine in the blood. Vitamin B12, folate and B6 help the body break it down.
Why it is done
Most often to assess vitamin B12, folate and B6 levels, and to screen newborns for the rare inherited condition homocystinuria.
Reading the results
- A high level can mean you are lacking B vitamins. Other causes include kidney disease, certain medicines and smoking.
- Homocysteine testing is not routinely recommended to assess heart disease risk, and lowering homocysteine has not been shown to reduce heart attack or stroke.
Reference ranges vary between laboratories in Australia, so check the range on your own report.
Before the test
Ask your doctor whether you need to fast or stop any foods or supplements.
What can affect the result
- Kidney disease
- Certain medicines
- Smoking
Related topics
Sources
Test information summarised from the sources listed on this page, read on 13 October 2026. General education only, not medical advice. Spotted a mistake? Please tell us through the HuBu-Intel contact page.