HOMOCYSTEINE, HEART ATTACKS, BIRTH DEFECTS
Report #7222
More than 10% of all heart attacks (1,2) and most cases of a birth defect called spina bifida (3) are caused by a buildup of a chemical called homocysteine.
Spina bifida means that the spinal bones do not close completely around the spinal nerves, causing babies to be born with nerve damage that can interfere with control of their legs, bladder and intestines. These babies are born to mothers who have a genetic defect in which they require more folic acid than normal (3). On the other hand, anyone increases his chances of developing a heart attack when he has low levels of folic acid by not eating enough liver, leafy green vegetables such as spinach and turnip greens and fresh uncooked fruits and vegetables such as asparagus, beets, beans and citrus fruits. Even small elevations of blood levels of homocysteine are associated with increased risk for heart attacks (4,5). 21 percent of North Americans over 60 have high blood levels of homocysteine and these people are three times more likely to suffer heart attacks.
Proteins in your body are made up of 21 building blocks called amino acids. Of the 21, 9 are essential and must come from the food you eat, while the other 12 are non- essential because your body can manufacture them from the essential nine. The non- essential amino acid, cysteine, must be made from the essential amino acid, methionine. The chemical reaction causes methionine to be converted to homocysteine, and then to cysteine. However, your body cannot convert homocysteine to cysteine unless you have enough available vitamins, pyridoxine, B12 and folic acid. A deficiency of any one of these three vitamins blocks the breakdown of homocysteine and causes large amounts to accumulate in your bloodstream. Homocysteine causes heart attacks by punching holes in arteries, starting plaque formation and then causing clots to form in the plaques. Lack of folic acid is more likely than B12 or pyridoxine to be the cause of heart attacks (6).
By Gabe Mirkin, M.D., for CBS Radio News
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acid.) You need at least 400 micrograms of folic acid a day to prevent homocysteine from
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acid, and 2-methylcitric acid. 18) J Lindenbaum, IH Rosenberg, PWF Wilson, SP Stabler, RH Allen. American Journal of
Clinical Nutrition 1994 (July);60(1):12-14. 19) LH Allen, J Casterline. American Journal of Clinical Nutrition
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mg cyanocobalamin. JB Ubbink, A Vandermerwe, WJH Vermaak, R Delport. Clinical Investigator
1993(Dec);71(12): 993-998. 21) homocysteine levels are associated with carotid artery stenosis. NEJM
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Reported 9/16/97; Checked 9/5/05