Siamak T. Nabili, MD, MPH
Dr. Nabili received his undergraduate degree from the University of California, San Diego (UCSD), majoring in chemistry and biochemistry. He then completed his graduate degree at the University of California, Los Angeles (UCLA). His graduate training included a specialized fellowship in public health where his research focused on environmental health and health-care delivery and management.
William C. Shiel Jr., MD, FACP, FACR
Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
In this Article
- What is homocysteine?
- Why is it important to monitor homocysteine levels?
- What are the possible symptoms or features of elevated homocysteine levels?
- What is considered a high level for homocysteine?
- What causes elevated homocysteine levels?
- Can elevated homocysteine levels be genetic?
- Can nutritional problems cause elevated homocysteine levels?
- How common is hyperhomocysteinemia?
- How can homocysteine levels be lowered?
- How many vitamins should I take to lower my homocysteine level?
- Does lowering homocysteine levels prevent heart attacks and strokes?
- What should I do to prevent heart attacks and strokes?
- Who should undergo testing for homocysteine blood levels?
What should I do to prevent heart attacks and strokes?
Losing excess weight, exercising regularly, controlling diabetes and high blood pressure, lowering the bad LDL cholesterol, and stopping cigarette smoking are crucial steps in preventing heart attacks and strokes. The association between homocysteine levels and atherosclerosis is generally weaker compared to the known risk factors of diabetes, high blood pressure (hypertension), high cholesterol level, and cigarette smoking.
It is recommended that healthy adults eat more fresh fruits and vegetable, eat less saturated fat and cholesterol, and take one multivitamin daily. One multivitamin will supply 400 mcg (microgram or one-one thousandth of a gram)/day of folic acid in addition to vitamins B6, B12, and other important vitamins.
Who should undergo testing for homocysteine blood levels?
Some doctors screen for elevated homocysteine levels in patients with early onset of blood clot formation, heart attacks, strokes, or other symptoms related to atherosclerosis, especially if these patients do not have typical risk factors, such as smoking cigarettes, diabetes, high blood pressure, or high LDL cholesterol levels.
Currently, there are no official recommendations as to who should undergo testing for homocysteine blood levels. Before more scientific data become available from the currently ongoing studies, many experts do not recommend a screening test for blood homocysteine levels, even in patients with unexplained blood clot formation. In addition, the consensus recommendation is against treating elevated homocysteine levels with vitamins to prevent heart disease.
There is also no consensus as to the optimal dose of folic acid and other B vitamins for the treatment of elevated blood homocysteine levels. (For example, treatment of patients with high homocysteine levels may require higher doses of folic acid and other B vitamins than the amounts contained in a multivitamin.) Therefore, a decision regarding testing should be individualized after consulting with your doctor.
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Previous contributing author: Dennis Lee, M.D.
Last Editorial Review: 8/8/2008
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