With hectic schedules, constant deadlines and a long list of what we are “supposed” to be doing, it is little wonder that Americans are constantly looking for a magic pill that will knock out all of their health concerns in one fell swoop.
For several years, researchers have pointed to B vitamins as a possible solution. One reason for this is homocysteine. Homocysteine is an amino acid that, when elevated, has been linked to pregnancy complications, cognitive impairment and mental disorders, as well as cardiovascular risks. As it turns out, B vitamins — most notably folic acid and vitamins B6 and B12 — have been shown to reduce homocysteine levels.
In fact, researchers have estimated that adding folic acid to foods has prevented some 17,000 deaths due to heart-related issues each year, while including folic acid in combination pills has reduced the risk for both cardiovascular disease and coronary heart disease. 
However, these benefits have not been shown in other cases. For example, when it comes to pre-existing vascular issues, one study found that folic acid does not appear to be beneficial for cardiovascular risk, and others showed using B vitamins to lower homocysteine levels did not prevent stroke.
Based on these conflicting results, a team of researchers performed a meta-analysis to determine the relationship between B vitamins and reduced risk of cardiovascular disease and all-cause mortality in people with existing vascular disease.
Checking the Research
Researchers scanned medical electronic databases for randomized, controlled trials that tested the effectiveness of B vitamins for treating cardiovascular disease (CVD), coronary heart disease (CHD), stroke and/or all-cause mortality. Nineteen studies were included and contained nearly 48,000 participants who ranged in age from 10 to 90 years old.
Researchers found that, in all cases, the B vitamin intervention reduced homocysteine levels. However, they did not note a significant reduction in outcomes for CHD, CVD, cardiovascular death or all-cause mortality. In fact, the only significant protective effect noted was for stroke.
Based on this, researchers concluded, “B vitamin supplementation was associated with a decrease in blood [homocysteine] levels and a significant protective effect on stroke. However, we found no significant benefit or harm of B vitamin supplementation on the risk of CVD, MI [myocardial infarction], CHD, cardiovascular death, or all-cause mortality.”
When it came to the lack of connection noted between B vitamins and the non-stroke conditions, there are several issues worth noting:
1. Testing of people with pre-existing conditions (treatment) versus healthy individuals (prevention).
2. Use of folic acid alone rather than in conjunction with B6 and B12.
3. Populations without folic acid deficiencies may not benefit from taking folic acid supplements.
4. Most studies looked at B vitamins as a secondary prevention measure, while one study specifically found that they exhibit a primary protective effect.
To B or Not To B
On the surface, this analysis seems to negate the effectiveness of B vitamins, but a closer look indicates quite the opposite.
First, all studies included found that B vitamin supplementation — regardless of form or amount — reduced homocysteine levels. Additionally, researchers found a positive association between B vitamin use and reduction in risk of stroke. Those are both reason enough to support the use of B vitamin supplements.
Given this, B vitamins appear to maintain their status as one of the best heart health nutrients. The key is to include the full B complex, as well as at least 400 mcg of folic acid, 50 mg of B6, and 1,000 mcg of B12.
 Bonaa KH et al. Homocysteine lowering and cardiovascular events after acute myocardial infarction. N Engl J Med. 2006;354:1578-88.
 Wald NJ and Law MR. A strategy to reduce cardiovascular disease by more than 80%. BMJ. 2003;326:1419.
 Verhaar MC et al. Folates and cardiovascular disease. Arterioscler Thromb Vasc Biol. 2002;22:6-13.
 Bazzano LA et al. Effect of folic acid supplementation on risk of cardiovascular diseases: a meta-analysis of randomized controlled trials. JAMA. 2006;296:2720-6.
 Toole JF et al. Lowering homocysteine in patients with ischemic stroke to prevent recurrent stroke, myocardial infarctions, and death: the Vitamin Intervention for Stroke Prevention (VISP) randomized controlled trial. JAMA. 2004;291:565-75.
 Huang T et al. Meta-analysis of B vitamin supplementation on plasma homocysteine, cardiovascular and all-cause mortality. Clin Nutr. 2012;1-7.
 Bazzano LA et al.