Supplementation of vitamin B to break down the levels of homocysteine, a naturally occurring amino acid linked to a higher risk of coronary heart disease and stroke, does not have beneficial effects on vascular outcomes, finds a new study.
Experts had theorized that homocysteine levels, influenced by genetics and diet negatively, affect a person's cardiac health by damaging the lining of blood vessels and promoting the formation of blood clots.
Earlier studies had indicated that the vitamins folic acid and vitamin B elevate the risk of cancer. However, the current findings establish that vitamin supplements do not promote tumors and have no adverse effect on the lethal disease.
Dr. Jane M. Armitage, professor of clinical trials and epidemiology at the University of Oxford and a principal author of the study stated, "This is another example of findings from observational studies leading us up the wrong path.
"While there is no doubt about the association between increased homocysteine levels and increased heart-disease risk, our results suggest that this is not a causal association. Lowering homocysteine does not reduce that risk.
“There is probably a third party involved that increases risk of heart disease and increases homocysteine at the same time. So lowering homocysteine should no longer be the focus of our attention.”
Impact of Vitamin B on heart disease assessed
In order to examine the impact of B-vitamin supplementation on heart-disease, stroke, and cancer rates in patients, the researchers conducted the Study of the Effectiveness of Additional Reductions in Cholesterol and Homocysteine (SEARCH).
The scientists enrolled 12,064 heart- attack survivors aged 18 to 80 years in the United Kingdom between 1998 and 2008.
Half the subjects were assigned to a tablet containing 2 milligrams (mg) of folic acid and 1 mg of vitamin B12 daily, while the remaining half were administered a placebo.
All the participants were tracked for around six to eight years.
According to experts, vitamins and other supplements are not a cure or treatment for any disease, but if incorporated into a healthy lifestyle they can cut the risk of several health-related issues and play a vital role in maintaining overall health.
Findings of the study
In the follow-up period, the researchers noted that the vitamins lowered the amount of the amino acid in patients' blood by 28 percent.
However, there was no difference in the rate of heart attacks, strokes, or coronary death between the two groups.
In addition, malignant tumors (excluding non-melanoma skin cancer) were diagnosed in 11.2 percent of the patients who were allocated folic acid plus vitamin B12 as opposed to 10.6 percent patients assigned placebo--the difference being quite insignificant.
Implications of the study
According to experts, vitamins and other supplements are not a cure or treatment for any disease, but if integrated into a healthy lifestyle they can cut the risk of several health problems and play a vital role in maintaining overall health.
The researchers concluded, "Taken together with the previous homocysteine-lowering trials, the results of SEARCH indicate that folic acid supplementation has no significant adverse effects on cancer or other major health outcomes, even if it also produces no beneficial effects on cardiovascular disease.
”In addition, these results highlight the importance of focusing on drug treatments (e.g., aspirin, statins, and antihypertensive therapy) and lifestyle changes (in particular, stopping smoking and avoiding excessive weight gain) that are of proven benefit, rather than lowering homocysteine with folic acid-based vitamin supplements, for the prevention of cardiovascular disease.”
The study has been published in the June issue of the Journal of the American Medical Association (JAMA).