Vitamin E is a fat soluble vitamin with anti-oxidant properties. Vitamin E is a combination of 8 related tocopherols and tocotrienols. The main one of these is alpha-tocopherol. 1 IU of vitamin E is the biological equivalent of 1mg of dl-alpha-tocopherol acetate. The U.S recommended daily amount for a 25-year old male for Vitamin E is 15 mg/day. Vitamin E is naturally found in almonds, asparagus, avocado, nuts, olives, seeds, spinach, wheat germ and vegetable oils such as canola, corn, sunflower, soybean, and cottonseed.
Vitamin E is used as a supplement for its benefit in many medical conditions.These include diabetes, cancer prevention, Alzheimers’s disease, Parkinson’s disease, premenstrual syndrome, cataracts and to lesson the harmful effects of dialysis, chemotherapy and radiation. It is also commonly used for preventing diseases of the heart and blood vessels, including high blood pressure. However, objective data on the latter benefit is lacking.
Over the last several decades, observational evidence has suggested that taking vitamin E prevents cardiovascular disease. The supporting logic was that vitamin E is an antioxidant and by preventing LDL oxidation, it may retard atherosclerosis. However, prospective clinical trials have not confirmed this benefit and have actually shown increased mortality in people taking this supplement. This information is important as 10%-20% of the adult western population takes multivitamins as supplements on a regular basis.
The most compelling evidence came from the Women’s Health Study. This trial was conducted between 1992 and 2004 in 39,876 healthy women aged 45 years and older. They were randomly assigned to receive 600 IU of Vitamin E or placebo and low-dose aspirin or placebo on alternate days. After a mean follow up for 10.1 years, data showed that vitamin E showed no benefit on the primary end point, major cardiovascular events, and no effect on secondary end points, including stroke and myocardial infarction. The results of this landmark trial were published in the July 6, 2005 issue of the Journal of the American Medical Association.
In another trial (HOPE and HOPE-TOO Trial) published earlier in the same year (Journal of the American Medical Association, March 2005), vitamin E recipients did not have any reduction in heart attacks, stroke or cardiovascular death, when followed for 7 years. There was however, a significantly higher risk of heart failure.
In a study published in the New England Journal of Medicine in 2000, researchers again failed to find any beneficial effects for vitamin E on the incidence of cardiovascular events in 9541 subjects. These patients were aged 55 or older and had known vascular disease or diabetes.
A recent meta-analysis has however significantly raised concern about the safety of vitamin E supplementation. Miller and colleagues combined data from 19 clinical trials involving 135,967 participants aged 47 to 84 years. These patients were at risk for chronic diseases, especially coronary heart disease. In 9 of the 11 trials testing vitamin E in doses of more than 400 IU/day, there was an increase in all-cause mortality. There also appeared to be a progressive increase in mortality if the dose of vitamin E was increased beyond 150 IU/day. This data was published in the Annals of Internal Medicine in November 10, 2004.
How about the benefits of vitamin E for other conditions?
Evidence based data on many common uses of vitamin E remains lacking. Vitamin E has been found to delay the progression of age-related macular degeneration Vitamin E supplementation have also found to have some beneficial effect in Alzheimer’s Disease, amyotrophic lateral sclerosis, and in infants born of HIV positive mothers.
What is the final word?
Forget about Vitamin E supplementation for cardiovascular protection. Although inexpensive and without side effects, it should not be used for this purpose. As a matter of fact, scientific data suggests that its use may be harmful to heart patients. There are other supplements like aspirin and fish oils that have a plethora of compelling scientific evidence supporting their heart protective benefits. Save your vitamin E money and spend it on a healthy diet or other beneficial supplements.
Dr. Shashi K. Agarwal is a Board Certified Internist and Cardiologist with a private practice in New York City and New Jersey. He is also a diplomate of the American Board of Holistic Medicine and the American Academy of Anti-Aging Medicine.