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What is homocysteine?

A high level of homocysteine has been linked to heart disease.

Homocysteine is an amino acid (a building block of protein) found in the bloodstream. Research has shown a link between high levels of homocysteine and an increased risk of coronary artery disease.

What does it do?

According to the American Academy of Family Physicians (AAFP), high levels of homocysteine may:

  • Damage blood vessel linings, leading to blockages.
  • Make blood more likely to form clots, which can block blood flow.

Should I be tested?

According to the AAFP, most people who have high levels of homocysteine don't get enough B vitamins. Paying close attention to your intake of folic acid, vitamin B6 and vitamin B12 can help return homocysteine to normal levels.

Citrus fruits, tomatoes, vegetables and grain products are good sources of folate, according to the American Heart Association (AHA).

What about supplements?

The AHA generally does not recommend taking folic acid or B vitamin supplements to reduce the risk of heart disease or stroke. Instead, the AHA recommends that everyone eat a balanced diet rich in fruits and vegetables.

If a healthy diet isn't lowering your levels, your doctor might recommend a supplement, according to the AAFP.

Reviewed 3/1/2024

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