I've written before on homocysteine and its reported link to heart attack risk. Many population studies have shown that slightly elevated blood levels of homocysteine were linked to an increased risk of heart attacks and strokes.
These results lead many doctors to measure homocysteine levels and to prescribe supplements of folic acid, which is known to lower homocysteine levels.
In my earlier entry, I wrote about the results of the Norwegian NORVIT trial presented at a meeting in Stockholm, which found that lowering homocysteine levels with folic acid supplements did not reduce the risk of heart attacks or strokes.
I said at that time that the question was not fully answered because full details of the study had not been published and that additional trials were needed to verify the findings.
Two recent published studies - the details of the NORVIT trial and the findings of a second, somewhat larger study - have now put to rest any notion that folic acid supplements will prevent cardiovascular disease.
The new study, called HOPE-2, randomly assigned 5,522 patients with known coronary heart disease or diabetes either to a placebo or to large doses of folic acid plus two other B vitamins. During a five-year follow-up, homocysteine levels fell by about 25 percent, but there was no associated significant reduction in heart attacks or deaths from cardiovascular disease.
The vitamin-treated group did have fewer strokes than those on placebo, but they also required significantly more hospitalizations for unstable angina. Participants taking folic acid in the NORVIT trial did not have fewer strokes.
In my opinion, these results indicate it's now time for doctors to stop prescribing folic acid supplements as a preventive measure against heart disease and for patients to stop taking them. Folic acid is still indicated for some pregnancies and other conditions, however.