Homocysteine is an amino acid that can build up in the blood if there are deficiencies in certain B vitamins (B6, B12, or folate). High levels of homocysteine are associated with an increased risk of heart disease and stroke.
Choline is oxidized to betaine, which is used to re-methylate homocysteine to methionine. Choline deficiency can lead to high homocysteine.
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Methionine is directly converted to homocysteine via several enzymatic steps. Elevated homocysteine is a marker of impaired methionine metabolism.
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