Homocysteine test: what it shows and when it is prescribed

What is homocysteine?
Homocysteine — is an amino acid that is formed in the body as a result of the metabolism of methionine — an essential amino acid that comes with food. Normally, homocysteine levels are maintained at a low level due to the work of enzymes and the presence of B vitamins (B6, B9 — folic acid, B12). An increase in the concentration of this amino acid in the blood (hyperhomocysteinemia) is associated with the risks of cardiovascular, neurological and metabolic disorders.

Why get tested for homocysteine?

Homocysteine testing is recommended in the following cases:

• Cardiovascular risk assessment: Elevated levels are associated with atherosclerosis, stroke, and thrombosis.

• Pregnancy planning: Folate deficiency and hyperhomocysteinemia can lead to miscarriages or fetal malformations.

• Suspicion of vitamin deficiency Group B: Especially for vegetarians or people with gastrointestinal diseases.

• Control of genetic disorders of folate metabolism (e.g., MTHFR gene mutations).

• Neurodegenerative disease risk assessment: Some studies link elevated homocysteine to Alzheimer's and Parkinson's diseases.

Normal homocysteine levels in the blood
Normal values may vary depending on the laboratory, but approximate reference ranges are:

• in adults: 5–15 μmol/L

• in children: 3–10 μmol/L

• in pregnant women: 4–12 μmol/L

Values above 15 μmol/L are considered pathological and may require medical intervention.

How to prepare for the analysis

• You need to take the test. on an empty stomach (at least 8 hours after the last meal).

• The day before the analysis, it is advisable to avoid alcohol, excessive physical exertion, and fatty foods.

• Tell your doctor about all vitamin supplements you take — especially vitamins B6, B9, and B12, as they can affect homocysteine levels.

Why homocysteine levels may be elevated

• Deficiency of folic acid, vitamin B12, B6

• Genetic mutations in folate metabolism enzymes

• Kidney disease

• Some autoimmune diseases

• Smoking, sedentary lifestyle

• Alcohol or coffee abuse

Methods for lowering homocysteine

• A diet rich in folate acid (leafy vegetables, legumes, liver)

• Taking vitamins B6, B9, B12 - under the supervision of a doctor

• Lifestyle changes: stress reduction, physical activity

• Treatment of concomitant pathologies, if detected

Homocysteine levels are not just a number in a test. Changes in them can signal serious problems that are important to detect early. Controlling this indicator helps reduce health risks and prevent future complications.