A deficiency of vitamin B12, folate, or vitamin B6 may increase your blood level of homocysteine, an amino acid normally found in your blood. There is evidence that an elevated blood level of homocysteine is an independent risk factor for heart disease and stroke. The evidence suggests that high levels of homocysteine may damage coronary arteries or make it easier for blood clotting cells called platelets to clump together and form a clot. However, there is currently no evidence available to suggest that lowering homocysteine level with vitamins will actually reduce your risk of heart disease. Clinical intervention trials are needed to determine whether supplementation with vitamin B12, folic acid, or vitamin B6 can help protect you against developing coronary heart disease.
The results of more than 80 studies indicate that even moderately elevated levels of homocysteine in the blood increase the risk of cardiovascular diseases, though the mechanism by which homocysteine increases the disease risk remains the subject of a great deal of research. The amount of homocysteine in the blood is regulated by at least three vitamins: folate, vitamin B12, and vitamin B6. Analysis of the results of 12 homocysteine-lowering trials showed folic acid supplementation (0.5-5 mg/day) had the greatest lowering effect on blood homocysteine levels (25 percent decrease); co-supplementation with folic acid and vitamin B12 (mean 0.5 mg/day or 500 mcg/day) provided an additional 7 percent reduction (32 percent decrease) in blood homocysteine concentrations. The results of a sequential supplementation trial in 53 men and women indicated that after folic acid supplementation, vitamin B12 became the major determinant of plasma homocysteine levels. Some evidence indicates that vitamin B12 deficiency is a major cause of elevated homocysteine levels in people over the age of 60. Two studies found blood methylmalonic acid (MMA) levels to be elevated in more than 60 percent of elderly individuals with elevated homocysteine levels. An elevated MMA level in conjunction with elevated homocysteine, in the absence of impaired kidney function, suggests either a vitamin B12 deficiency or a combined B12 and folate deficiency. Thus, it is important to evaluate vitamin B12 status as well as kidney function in older individuals with elevated homocysteine levels prior to initiating homocysteine-lowering therapy.
Although increased intake of folic acid and vitamin B12 has been found to decrease homocysteine levels, it is not presently known whether increasing intake of these vitamins will translate to reductions in risk for cardiovascular diseases. However, several randomized placebo-controlled trials are presently being conducted to determine whether homocysteine lowering through folic acid and other B vitamin supplementation reduces the incidence of cardiovascular diseases. A meta-analysis of data from four of the ongoing trials shows that B vitamin supplementation had no significant effect on risk of coronary heart disease or stroke, but only about 14,000 participants were included in analysis and thus any conclusions are limited. Nevertheless, the completion of ongoing clinical trials should help to answer whether or not supplemental B vitamins lower risk for cardiovascular diseases.
To Your Continued Good Health,
Kim Buchanan
TriVita Business Affiliate 11225081
http://trivitaproduct.info/
http://www.trivitaproduct.info/b12
http://vitamin-b12-supplements.blogspot.com/
Resource: Linus Pauling Institute
Micronutrient Research for Optimum Health
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