Symptoms and Signs of Homocysteine Blood Test

Medical Author:
Medically Reviewed on 2/24/2022

Doctor's Notes on Homocysteine Blood Test

Homocysteine is an amino acid. Normal levels in the blood vary between 4-15 micromoles/liter. There are no signs or symptoms of elevated, normal, or low levels. However, high levels have been associated with heart disease, cardiovascular disease, angina, dementia, Alzheimer's disease, miscarriage, premature birth, maternal thrombosis, and osteoporosis. The blood test is used to detect high levels to help diagnose infants and young adults with a family history of the problem and in individuals with medical conditions like stroke or heart attacks with no other risk factors, eye lens dislocations, mental retardation, or Marfan syndrome (genetic connective tissue disorder).

Causes of homocysteine levels (high levels) are influenced by genetics and diet. For example, vitamins B6 and B12 help regulate homocysteine levels while stress and caffeine may raise its level. Genetics may play a role as evidenced by a rare, inherited disease (homocystinuria) where homocysteine is found elevated in the urine of infants leading to eye, bone, and other abnormalities.

What Are the Treatments for High Levels of Homocysteine?

The high levels are caused by diet and/or likely genetics. Treatments are mainly dietary and/or vitamin supplements:

  • Diet increases (vitamin B6, B12, folic acid or folate)
    • Green vegetables
    • Orange juice
    • Beans
    • Avoid high intake of coffee and alcohol
    • Quit smoking
  • Vitamin supplements
    • Over-the-counter daily supplements containing folic acid and vitamin B6, B12
    • Prescription-strength folic acid and vitamin B6, B12

Your doctor may do additional tests to detect any underlying conditions that may contribute to the high levels of homocysteine.

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Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.