Vitamin E and Heart Disease Risk
Because of the cost of pharmaceuticals and the desire of most individuals to avoid medications if possible and rely on more natural and lifestyle changes, there has been a burgeoning health food and homeopathic medication market that Americans spend billions of dollars on annually.
The well publicized news about the withdrawal of previously Food and Drug Administration approved drugs like Vioxx, Baycol, Rezulin, Posicor and others because of previously unrecognized toxicity has only fueled the growth of “natural” treatments. However, it now appears that a staple of the self-help therapies, vitamin E, may not work as hoped. It could even be deleterious. There's a larger message here that the public should take away from all of this, and it's NOT the mantra of the paranoid: trust no one. But I will get to that message soon enough.
Last week at the annual scientific session of the American Heart Association in New Orleans and concurrently published in a prestigious peer-reviewed medical journal, a careful combined analysis of 19 international studies involving vitamin E which included 136,000 individuals (mostly over age 60) was analyzed for evidence of benefit. Alarmingly, these investigators from Johns Hopkins University found that high dose vitamin E was associated with a ten percent increase in mortality compared to those on low dose vitamin E. High dose was defined as 400 international units or more, which is a dose commonly used by my patients who choose to take vitamin supplements. The vitamin E dose in multivitamins are much lower and have not been shown to be harmful.
Vitamin E has become popular because of the flurry of information surrounding the purported damaging effects of oxidation in the body. Oxidative injury chemically means the stripping off of electrons from molecules that make these molecules much more reactive and potentially damaging to surrounding tissues. Vitamin E, amongst others, is a potent anti-oxidant and has been touted as being protective against the effects of aging, heart disease, cancer and other conditions. The anti-oxidant effect of vitamin E has been amply demonstrated, and in limited clinical studies, has been shown to be possibly beneficial.
Regular readers of this column, and certainly my patients, know that I am an advocate of evidence-based medicine, usually predicated on the results of blinded randomized clinical trials. Several of these columns, including the recent one on the safety data of Vioxx, detail how clinical trials are used to gather information of benefit or harm. Indeed, the Ventura Heart Institute is active in such scientific endeavors and I have lectured on the results of these studies for years. A few years ago, a clinical trial with the acronym HATS suggested that vitamin E blunted the benefit from statins. This was a small study involving not even two hundred patients, but the data were quite compelling. I began to suggest to my patients that vitamin E was not as helpful as the observational data intimated it may be, and that those on statins should consider stopping it.
Because the HATS trial was small, the results were viewed as only preliminary data. Subsequently, data from larger clinical trials with the acronym HOPE trial and the Heart Protection Study also had antioxidant vitamin treatments and showed no benefit. Because these trials involved tens of thousands of patients, the antioxidant story was felt to be finished. What is different about this recent study is the suggestion that large dose vitamin E may actually be harmful. Data on another antioxidant vitamin, beta-carotene, was similar in prior studies and actually seemed to increase the risk of certain cancers.
It is unknown on how megadoses of vitamin E may be harmful, though some speculate that such large doses may deregulate the body's natural antioxidant checks and balances. And what makes vitamin E and beta-carotene potentially worse than large doses of vitamin C is that water-soluble vitamin C washes out of the body through the kidneys if it can't be used. Fat-soluble vitamins E and beta-carotene accumulate in your fat storage tissues, conceivably to toxic concentrations.
Vitamins, by definition, are vital for life. There are 13 essential vitamins the human body cannot make and must take in from the diet. However, it would now seem that natural sources of vitamin E are likely the best. Green, leafy vegetables, nuts and vegetable oils tend to be excellent sources of vitamin E.
The health food industry trade associations (lobbyists) and undoubtedly the vitamin store chains are already gearing up to criticize and minimize the results of these new data. It would seem that all they need to do is show objective, randomized clinical trial data of outcome benefit, against the now wealth of data showing at best, no benefit, and at worst, potential harm. Until then, like in business and politics, the Watergate Rule applies: follow the money.