Semin Vasc Med 2005; 5(2): 110-123
DOI: 10.1055/s-2005-872397
Copyright © 2005 by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001 USA.

Dietary Determinants of Plasma Homocysteine Concentrations

Petra Verhoef1 , 2 , Lisette C.P.G. M. de Groot1
  • 1Division of Human Nutrition, Wageningen University, Nutrition and Health Programme, Wageningen, The Netherlands
  • 2Wageningen Centre for Food Sciences, Nutrition and Health Programme, Wageningen, The Netherlands
Further Information

Publication History

Publication Date:
27 July 2005 (online)

ABSTRACT

Severe hyperhomocysteinemia is typically caused by rare enzymatic defects or by renal failure. In contrast, mild to moderate hyperhomocysteinemia chiefly results from suboptimal status of nutritional factors involved in homocysteine metabolism. Low dietary intake of folate is the most important nutritional cause of elevated homocysteine (tHcy) concentrations. Folic acid is more effective than dietary folate in lowering tHcy concentrations, and a daily dose of 400 μg of folic acid is the minimum daily dose associated with the maximum tHcy-lowering effect (∼20-25% reduction). Mean fasting tHcy concentrations have dropped substantially in populations with mandatory folic acid fortification, and other B-vitamins, such as vitamin B12, are important determinants of tHcy levels in this setting. Vitamins B2 and B6 have little influence on fasting tHcy concentrations, although the former may be relevant in individuals with the MTHFR 677 TT-genotype, and the latter may improve tHcy catabolism in elderly individuals. Betaine and choline can lower fasting tHcy concentrations to a similar extent as folic acid, particularly in the setting of a high intake of methionine. Consumption of tea and coffee increase tHcy concentrations by up to 20%. A high-protein meal also increases tHcy, but these changes are transient, and levels return to normal after an overnight fast. Serine and cystine also influence the methionine-induced postprandial rise in tHcy concentrations. In conclusion, alteration in dietary intake or use of folic acid supplements can substantially lower tHcy concentrations. However, it is not known whether lowering tHcy levels can reduce the risk of cardiovascular disease or cognitive decline or prevent pregnancy complications or osteoporosis.

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1 Throughout this article, “folic acid” refers to the oxidized form of the vitamin, as used in supplements and food fortification, whereas “folate” refers to all vitamers, either in blood, tissue, or food.

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 Dr.
Petra Verhoef

Division of Human Nutrition, Bomenweg 2

6703 HD Wageningen, The Netherlands

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