(LifeWire) - You take a daily multivitamin to ensure proper nutrient intake. You're hooked on green tea. Now you're wondering if taking vitamins can lower your cholesterol levels.
Arguments for supplementation tend to be anecdotal, historical or both, but not scientifically rigorous. Placebo-controlled, double-blind studies, the gold standard of western science, are in short supply. Studies cost millions; vitamins and minerals cannot, generally speaking, be patented, and thus reap profit for those who fund the studies.
Vitamins for Cholesterol
When it comes to vitamins for cholesterol reduction, so far, the evidence that does exist is largely negative.
This evidence comes with the exception of niacin, more specifically nicotinic acid, which lowers "bad cholesterol" (LDL) and raises the "good cholesterol" (HDL). But even here the news is not all good: Talk to your doctor before trying niacin.
The Good and the Bad
Here's why you should consult with your doctor before taking niacin:
But the bad news is that the American Heart Association (AHA) says niacin has side effects -- some quite serious. Skin flushing, stomach irritation, dizziness, headache, skin rashes, elevated blood glucose and even liver damage can come with the niacin/statin combination. Higher blood glucose is a special worry for those with diabetes, although newer formulations of the supplement seem to be safe if combined with "good glycemic control."
An evidence-based literature review (by Uptodate.com) indicated possible complications have been found from taking niacin. One is gouty arthritis, and in subjects treated with vasodilators (niacin) who have elevated plasma homocysteine levels, they had dangerously low blood pressure. This "may negate its [niacin's] favorable effects on the lipid profile in certain subsets of patients," according to the review.
Nonprescription niacin products present their own problems. Ones marked "no-flush" may not be able to lower cholesterol. "Sustained-release" products have the potential to do serious liver damage. Plain old "immediate -release" niacin often causes skin flushing and other annoying side effects.
Benefits of Antioxidants?
What about the benefits of taking antioxidants in general to lower cholesterol and the risk of CVD? The AHA's position is that the data do not support the use of vitamin or mineral supplements. "Scientific evidence does not suggest that consuming antioxidant vitamins can eliminate the need to reduce blood pressure, lower blood cholesterol or stop smoking cigarettes," the association says.
One piece of evidence that the association cites is the Women's Antioxidant and Folic Acid Cardiovascular Study (WAFACS). Findings reported at the AHA's Scientific Sessions in 2006 found neither benefit nor harm from using vitamins C, E, B6, B12, folic acid or beta-carotene to lower cholesterol and reduce the risk of CVD. The women in this study were health professionals over 40 years of age who were considered to be at high risk for CVD, because of either a history of the disease or three or more risk factors, including high blood pressure, high cholesterol levels, diabetes and/or smoking.
Vitamin E Versus CVD
Interestingly, that study found that women who had already had CVD and who took supplemental vitamin E had a "significant reduction in cardiovascular events." The researchers recommended this be studied further.
The authors of a 2007 study published in the Archives of Internal Medicine on the antioxidant part of the Women's Antioxidant Cardiovascular Study noted, "Single antioxidants may not reflect the complex vitamins and nutrients found in foods, which may explain the discrepancies between most intervention trials and studies of fruits and vegetables."
With the exception of nicotinic acid, vitamins and minerals seems to yield no cholesterol benefit, according to current scientific evidence, but a diet of food does when it is high in vitamins and minerals. The AHA recommends a diet loaded with fruits, vegetables, whole grains and nuts -- all sources of heart-healthy antioxidants and other nutrients.
The American Journal of Cardiology published a study in 2003 found that lifestyle changes -- such as exercise and a diet focused on whole grains and produce -- can result in significant improvements in plasma lipids, blood pressure and body weight.
As always, consult a physician for more information on cholesterol reduction.
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