Niacin, Vitamin B3

I know this information is already about a year out of date but I thought it might be worth republishing (as I just ran into this article and study this last weekend.) At the 2009 meeting of the American Heart Association, a study published in the New England Journal of Medicine showed that niacin (vitamin B3) treatments worked better than the Merck prescription drug Zetia at reducing the size of arterial blockages in the neck. Quoted from the New York Times who covered the story fairly well:


For patients taking a statin to control high cholesterol, adding an old standby drug, niacin, was superior in reducing buildup in the carotid artery to adding Zetia, a newer drug that reduces bad cholesterol, according to a new study.

The small study, with only 208 patients, has attracted outsize attention because the researchers did a head-to-head comparison of niacin and Zetia, which has been heavily marketed.

The Food and Drug Administration approved Zetia in 2002 to lower bad cholesterol, a risk factor for heart disease. But the drug has not yet proved to have a longer-term clinical benefit in reducing heart attacks and deaths. Merck, the maker of the drug, is conducting a clinical trial on that issue involving up to 18,000 patients.

The headline jumps out because a measly vitamin that has been available since humans existed appears to do more for the cardioprotection than Merck’s newest drug. But lets dig a little deeper here and keep a good head about you as we dig in here:


Carotid Artery (the big one shown)

1) The study showed that niacin was more effective solely at preventing plaques from forming in the carotid artery which runs up from the aorta into your neck. While blockages here matter, this artery is much larger than the the coronary arterials. Blockages in the coronaries cause heart attacks by depriving the heart’s ventricles of blood. It would logically follow that other arteries besides the carotid would remain less clogged based on the study but that was not proven here.


2) Zetia did lower LDL cholesterol a significant amount – about 20%. But this reduction has a very interesting side effect: it made the arterial plaque worse. From the NEJM study:

As compared with ezetimibe, niacin had greater efficacy regarding the change in mean carotid intima–media thickness over 14 months (P=0.003), leading to significant reduction of both mean (P=0.001) and maximal carotid intima–media thickness (P≤0.001 for all comparisons). Paradoxically, greater reductions in the LDL cholesterol level in association with ezetimibe were significantly associated with an increase in the carotid intima–media thickness (R=–0.31, P<0.001)

If we translate that bold part into english: Zetia lowered LDL but that made the artery plaque bigger. The scientists did not go into greater detail here and all the study participants had heart disease, so it is hard to draw conclusions here, but this finding may mean Zetia is doing more harm than good. Even more broadly, it brings into question the idea of blanket lowering LDL cholesterol dogma that is the foundation of most heart disease protocols.

3) This study is flawed because it did not use a placebo group and there was no mention of the study being double blinded (that is where neither the patients nor the scientists know whom is receiving which treatment).

4) The form of niacin used in this study was not the OTC Vitamin B3 Niacin but rather an extended release Rx version called Niaspan. So, of course, the kicker from the Times story hits hard:

Niaspan is made by Abbott Laboratories, which financed the study.

Some final thoughts:

The findings are significant but not terribly meaningful – this was a small study that did not have the proper rigor to demonstrably usher in a new paradigm, not to mention the findings conveniently coincide with the pharmaceutical company who funded the study. But it did show Abbott’s Niacin-based drug beats Merck’s Zetia. It would be interesting to see if, instead of using Abbott’s time release formula, there was a side-by-side comparison of what 2X/day niacin supplement, in all its $4.99/bottle-at-walmart-glory, might do next to the $100+/bottle of miracle drug Zetia, and even Abbott’s Niaspan. Some placebo controls would be nice as well.

The irony to this whole story is that regular old niacin can be found in the very products cardiologists tell you stay away from: beer, pork, fish and -above all – chicken. This situation seems just too convenient to be an accident. Just putting an idea out there – maybe the body evolved to use niacin as a natural cholesterol balance against cholesterol heavy foods like beef and chicken, considering the body would find niacin wherever it would find cholesterol in these meat products.

Any thoughts on that?