Methionine and Homocysteine Ratio in Blood (Mass Fraction)
This test measures the ratio of methionine to homocysteine in your blood, which can help assess your risk for certain health conditions.
["Understanding your methionine-homocysteine balance may help identify risks for heart disease or other metabolic issues."]
Key facts at a glance
- LOINC
- 55942-7
- Short code
- MetHgb MFr BldCo
- Synonyms
- MetHgb MFr BldCo
- Category
- hematology
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Ref low
- 12
- Ref high
- 17.5
- Critical range
- 7 N/A – 20 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 85018
- SNOMED
- 900000000000003004
- Specimen volume
- 3 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
Why This Test Might Be Ordered
Your healthcare provider may recommend this test if you have a history of cardiovascular disease, high blood pressure, diabetes, or kidney problems. It may also be used to monitor certain genetic conditions or metabolic disorders.
What to Expect Before the Test
No special preparation is typically required, but you may be asked to fast for a few hours before the blood draw. Wear a loose-fitting shirt for easy access to your arm.
What Happens During the Test
A healthcare professional will insert a small needle into a vein in your arm to collect a blood sample. You may feel a slight pinch, but the procedure usually takes only a few minutes.
What the Results Mean
Your results will show the ratio of methionine to homocysteine in your blood. While specific reference ranges vary by lab, higher ratios may be associated with increased risks for heart disease or other vascular conditions.
Reference range
Adult males: 13.5-17.5 g/dL; Females: 12.0-16.0 g/dLN/A
No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Elevated homocysteine levels (often assessed indirectly through this ratio) are linked to an increased risk of blood clots, heart disease, and stroke. This test helps evaluate whether your methionine-to-homocysteine balance is within a healthy range, potentially guiding preventive care or lifestyle adjustments.
Short name
Methionine-Homocysteine Ratio
Frequently asked questions
What causes an abnormal methionine-homocysteine ratio?
How can I lower my methionine-homocysteine ratio if it’s high?
Does this test require fasting?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy