A new study confirms laboratory findings that suggest vitamin E can promote oxidation in the human body under certain conditions -- specifically, in smokers eating a diet high in polyunsaturated fat.

Oxidation is a chemical reaction in the body that can produce harmful molecules that damage tissue. Antioxidants -- such as vitamin E -- are believed to help fight certain illnesses by blunting the effects of oxidation.

In some past studies, vitamin E has not been protective against heart or blood vessel disease caused by atherosclerosis, or hardening of the arteries.

Some data suggest that it actually increases the risk of heart attack and stroke.

To see if vitamin E can function as a pro-oxidant, meaning it promotes oxidation rather than fighting it, researchers assigned 10 people who smoked more than one pack of cigarettes per day to follow a diet high in monounsaturated fat for 3 weeks, then a diet high in polyunsaturated fat for 3 weeks.

People in the study had increased levels of F2-isoprostanes and prostaglandin F2-alpha, chemicals that indicated oxidation was taking place.

Then the researchers added 800 IU vitamin E per day to the polyunsaturated fat diet.

After 3 weeks they found that there was even more oxidation. Mean levels of F2-isoprostanes and prostaglandin F2-alpha increased further.

Arteriosclerosis, Thrombosis and Vascular Biology 2001;21:1029-1033

Dr. Mercola's Comments:

Although the vast majority of people seem to benefit from vitamin E, that certainly is not universally true. Additionally, individuals who have above average levels of long chain fatty acids in their body (carbons greater than 20) usually have some type of acquired metabolic defect in taking vitamin E. This will actually make them worse as the vitamin E is a potent inhibitor of beta oxidation of long chain fats. Unfortunately, the only effective way to find out if you have elevated long chain fatty acids is to perform an $300-$400 serum fatty acid test. The best one is from Johns Hopkins. I do find that most people benefit from vitamin E, and it is one of the few supplements I personally take. Ideally one should have some sort of energetic evaluation to determine if the supplement is useful for their body. Fortunately, this is something that we routinely do in our office. The article is presented to alert you that not all vitamins are good for everyone and they need to be used wisely and with great care and selection. If you do supplement with vitamin E, Living Fuel Omega & E comes with my highest recommendation. These are pure, very high-quality fish oil capsultes that contain both the omega-3 that is so severely lacking in most people's diets AND the full-spectrum vitamin E that is the form of vitamin E you should be taking. Read about Living Fuel Omega 3 & E now. Related Articles: Vitamin E-Who Are You Going to Believe? Vitamin E Supplements May Cause Harm