Your Health

Homocysteine and Heart Disease

Back to Previous Page

What Is Homocysteine?

HCA image for aging hearts Homocysteine is an amino acid formed in the body from another amino acid called methionine. Certain B vitamins are needed to breakdown these amino acids. The vitamins include vitamin B6, vitamin B12, and folate. A deficiency of any one of these vitamins, most particularly folate, can lead to an elevation in blood levels of homocysteine.

Does Homocysteine Increase the Risk of Heart Attack?

Levels of homocysteine increase with age, and elevation is more common in men and postmenopausal women. Although some studies have found and association with high homocysteine levels and heart disease, whether or not homocysteine is a risk factor for heart disease remains controversial.
Very high levels of homocysteine were first found to be a problem in the 1960s, when people with an inheritable defect of an enzyme responsible for the metabolism of homocysteine were suffering from heart attacks and strokes before the age of 30. In the 1970s, researchers began to study the effects of lifestyle factors, such as dietary folate and smoking, in people who developed elevated homocysteine levels. During the last two decades, a connection between mild to moderate elevations of homocysteine and heart disease has shown up in some, but not all studies. And organizations like the American Heart Association (AHA) do not currently identify high homocysteine levels as a major risk factor for cardiovascular disease.
If you have not yet been tested, do not be surprised if your doctor is somewhat reluctant to measure your homocysteine level. If other risk factors for heart disease are already present, knowing that your homocysteine level is elevated may not change your treatment. However, according to the AHA, getting screened for homocysteine levels may be useful if you have a personal or family history of cardiovascular disease and do not have the common risk factors, like smoking, high blood pressure, high cholesterol.

What If You Have Elevated Homocysteine Levels?

Homocysteine levels are reduced when intake of folate, vitamin B6, and vitamin B12 is increased. However, studies have not shown that taking these vitamins can prevent or treat cardiovascular disease.
The AHA suggests that people at high risk should make sure they are getting enough folate, vitamin B6, and B12 in their diet. Your doctor can give you specific recommendations about the appropriate dosages for you. Here are the general recommendations for daily intake of folate, vitamin B6, and B12:
  • Folate
    • Males and females aged 14 and older—400 micrograms (mcg)
  • Vitamin B6
    • Males aged 19-50 years—1.3 milligrams (mg)
    • Males aged 51 years and older—1.7 mg
    • Females aged 19-50 years—1.3 mg
    • Females aged 51 years and older—1.5 mg
  • Vitamin B12
    • Males and females aged 14 years and older—2.4 micrograms
Here are a few examples of foods that are high in these vitamins:
  • Folate—citrus fruits, fortified breakfast cereal, vegetables
  • Vitamin B6—fortified breakfast cereal, bananas, baked potatoes with skin
  • Vitamin B12—fortidied breakfast cereal, fish, meat, poultry, and dairy products
If you are concerned about your risk factors for heart disease or if you would like to take supplements, talk to your doctor. The two of you can decide what the best approach would be based on your health and diet.

RESOURCES

American Heart Association http://www.americanheart.org/

National Heart, Lung, and Blood Institute http://www.nhlbi.nih.gov/

References

Coronary Artery Disease: High Homocysteine Level: How It Affects Your Blood Vessels. American Academy of Family Physicians Family Doctor website. Available at: http://familydoctor.org/familydoctor/en/diseases-conditions/coronary-artery-disease/causes-risk-factors/high-homocysteine-level-how-it-affects-your-blood-vessels.html. Updated July 2010. Accessed December 14, 2012.

Homocysteine and cardiovascular disease. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed/what.php. Updated November 2, 2012. Accessed December 14, 2012.

Homocysteine, folic acid, and cardiovascular disease. American Heart Association website. Available at: http://www.heart.org/HEARTORG/GettingHealthy/NutritionCenter/Homocysteine-Folic-Acid-and-Cardiovascular-Disease%5FUCM%5F305997%5FArticle.jsp. Updated January 20, 2012. Accessed December 14, 2012.

Eikelboom JW, Lonn E, Genest J Jr, et al. Homocysteine and cardiovascular disease: a critical review of the epidemiologic evidence. Ann Intern Med.1999 Sep 7;131:363-375.

Hankey GJ, Eikelboom JW. Homocysteine and vascular disease. Lancet. 1999;354:407-413.

Liem A, Reynierse-Buitenwerf GH, Zwinderman AH, Jukema JW, van Veldhuisen DJ. Secondary prevention with folic acid: Effects on clinical outcomes. J Am Coll Cardiol. 2003;41:2105–2113.

Moustapha A, Robinson K. Homocysteine: an emerging age-related cardiovascular risk factor. Geriatrics .1999;41:49-51.

Pyridoxine. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed/what.php. Updated May 16, 2011. Accessed December 17, 2012.

Schnyder G, Roffi M, Flammer Y, Pin R, Hess OM. Effect of homocysteine-lowering therapy with folic acid, vitamin B12, and vitamin B6 on clinical outcome after percutaneous coronary intervention: the Swiss Heart study: a randomized controlled trial. JAMA. 2002;288:973–979.

Stein JH, McBride PE. Hyperhomocysteinemia and Athrosclerotic Vascular Disease: Pathophysiology, Screening, and Treatment. Arch Intern Med. 1998;158(12):1301-1306.

Vitamin B12. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed/what.php. Updated December 14, 2011. Accessed December 17, 2012.

Revision Information

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

Copyright © EBSCO Publishing
All rights reserved.