Posted on 09/21/2007 3:47:19 PM PDT by decimon
CORVALLIS, Ore. – Generations of studies on vitamin E may be largely meaningless, scientists say, because new research has demonstrated that the levels of this micronutrient necessary to reduce oxidative stress are far higher than those that have been commonly used in clinical trials.
In a new study and commentary in Free Radical Biology and Medicine, researchers concluded that the levels of vitamin E necessary to reduce oxidative stress – as measured by accepted biomarkers of lipid peroxidation – are about 1,600 to 3,200 I.U. daily, or four to eight times higher than those used in almost all past clinical trials.
This could help explain the inconsistent results of many vitamin E trials for its value in preventing or treating cardiovascular disease, said Balz Frei, professor and director of the Linus Pauling Institute at Oregon State University, and co-author of the new commentary along with Jeffrey Blumberg, at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University.
“The methodology used in almost all past clinical trials of vitamin E has been fatally flawed,” said Frei, one of the world’s leading experts on antioxidants and disease. “These trials supposedly addressed the hypothesis that reducing oxidative stress could reduce cardiovascular disease. But oxidative stress was never measured in these trials, and therefore we don’t know whether it was actually reduced or not. The hypothesis was never really tested.”
The level of vitamin E that clearly can be shown to reduce oxidative stress, new research is showing, is far higher than the level that could be obtained in any diet, and is also above the “tolerable upper intake level” outlined by the Institute of Medicine, which is 1,000 I.U. a day. OSU researchers are not yet recommending that people should routinely take such high levels, but they do say that controlled clinical trials studying this issue should be aware of the latest findings and seriously consider using much higher vitamin E supplement levels in their studies.
In lab, animal or human studies, there’s evidence that vitamin E can reduce oxidative stress, inhibit formation of atherosclerotic lesions, slow aortic thickening, lower inflammation, and reduce platelet adhesion. Some human studies using lower levels of vitamin E supplements, such as 100 to 400 I.U. a day, have shown benefits in reducing cardiovascular disease risk, and others have not. An underlying assumption was that these levels were more than adequate to reduce oxidative stress, since they far exceeded the “recommended dietary allowance” or RDA for the vitamin, a level adequate to prevent deficiency disease.
“What’s now clear is that the amount of vitamin E than can conclusively be shown to reduce oxidative stress is higher than we realized,” Frei said. “And almost none of the studies done with vitamin E actually measured the beginning level or reduction of oxidative stress.”
Proper studies of vitamin E, researchers say, must be done carefully and take into account the newest findings about this micronutrient. It’s now known that natural forms of the vitamin are far more readily absorbed than synthetic types. It’s also been discovered that supplements taken without a fat-containing meal are largely useless, because in the absence of dietary fat vitamin E is not absorbed.
Some clinical trials may wish to study the long term effect of vitamins on healthy individuals. But if a clinical trial seeks to learn the value of reducing oxidative stress, they should select patients in advance for those who have high, measurable oxidative stress – often people who are older or have a range of heart disease risk factors, such as obesity, poor diet, hypertension or other problems. Cognizance should also be taken of people with health issues that may further increase their vitamin needs, such as smokers.
“A pill count simply isn’t enough to determine the value of vitamin E,” Frei said. “We need to select people for trials properly, make sure they are taking the right form of the vitamin, at the right levels and at the right time, and then verify the metabolic results with laboratory testing.”
“Only when we do these studies right will we answer questions about the value of vitamin E in addressing cardiovascular disease,” he said. “So far we’ve been flying blind.”
A parallel, Frei said, would be presuming to test the value of a statin drug, which lowers cholesterol, without ever measuring cholesterol levels in the test subjects, neither at the beginning nor at the end of the study. Such trials would be ridiculed in the science community.
So far, that’s the way vitamin E has been studied.
The use and intake of vitamins, experts say, has traditionally been thought of in terms of overt deficiency – for example, not enough vitamin C causes scurvy. Much less research has been done on the levels that can help create optimum health. The issue is of special importance with modern populations that have very different diets, activity levels and increased lifespan, and are dying from much different causes – predominantly heart disease and cancer – than people of past generations.
...snip...
Adults should avoid taking vitamin E preparations in amounts of 400 IU or more. Experts should reconsider the stated upper tolerable intake level of vitamin E. Sellers should consider removing vitamin preparations that contain 400 IU or more per dose from stores.
I'll stick with my original comment: "Maybe it's a combination of beneficial vitamins that are...uhh...beneficial."
I agree. Eat the right stuff, and it will help you. Maybe.
But don’t eat the wrong stuff. It could hurt you, probably.
First it’s good for you, then it’s not! What’s a person to do?
I don’t even want to take my Calcium/Mag/Vit D because I heard that you should put one in vinegar and it it doesn’t dissolve, it might not dissolve in your system. I did it and the pill just sat there...24 hours and it looked just the same as when I placed it there.
So-—do I get my $$’s worth? Sounds like in a few years they always change their minds.
And most of all...be decisive. :-)
Well...if you’re curious enough then you could start looking for evidence of the pill not having dissolved.
Everytime I take vitamin E regularly, after about four or five days, I feel like sh*t. Draggy, crappy, sluggish ... I stop taking the vitamin E, and I go back to normal.
Never have figured it out.
A recent article stated that 90% of all over the counter vitamins available in the USA are imported from China, Hmmmm......
The study, conducted by Boris P. Fecalhead, PhD, MD, BFD, instilled 2 1/2 gallons of distilled water through nasal gastric tubes directly into the stomachs of the white mice daily. Virtually all of the white mice died within hours or days of the onset of the treatment.
Dr. Fecalhead stated that this was conclusive evidence that distilled water should never be taken internally and should be banned from all supermarket shelves, in order to protect consumers. While admitting that there could be some difficulty in translating the study and dosages to humans, he felt that the high mortality resulting from the use of distilled water should be taken seriously and warned that until more studies are done, distilled water should be banned by the FDA and warning labels should be required advising of the danger when taken internally.
Dr. Fecalhead said he has applied for a 14 million dollar grant from the government to do further research on this subject. His previous research was done with similar methodology- direct intravenous infusions of 180 proof alcohol directly into the superior vena cava of mice. He stated that his study virtually proved that alcohol should be removed from any human usage as again virtually all of the mice died within hours of the onset of the experiment.
Dr. Fecalhead received his degree in medicine from the University of Grenada in 1927, and is director emeritus and honorary Sheethead and Chairman of the School of Feelgood Research and Woodworking at the Al Gore Community College in Granville, Tenn. He received his PhD from Jose's College of Deep Thought and Taco Stand, in Costa Lotta, Mexico after writing his dissertation on "Socialism, Liberalism and Other Rectal Cranial Inversions" (with the table of contents and index, it was four double spaced pages in length, but made everyone in the department feel good).
I have a faint memory trace of a study showing that 800 units of E were destructive to some folks for I forget the reason. You recall that study?
Well, it is handy for helping you to grasp new concepts.
;-)
Everytime I take vitamin E regularly, after about four or five days, I feel like sh*t. Draggy, crappy, sluggish ... I stop taking the vitamin E, and I go back to normal.
I take B-100, C, Beta Carotene and E. If I forget for a few days I get joint pain.
I’ve never felt the effects you experienced when I take E.
First it’s good for you, then it’s not! What’s a person to do?
I don’t even want to take my Calcium/Mag/Vit D because I heard that you should put one in vinegar and it it doesn’t dissolve, it might not dissolve in your system. I did it and the pill just sat there...24 hours and it looked just the same as when I placed it there.
The HCl acid in your stomach is much stronger than the acetic acid in vinegar. However, the point is a good one - minerals like Ca and Mg come in various forms (compounds) and some are absorbed more readily than others. For those minerals, I try to stick with the citrates rather than oxides or carbonates.
So-—do I get my $$’s worth?
You probably did. The cheap forms are usually oxides. It's like anything else; you have to do some homework, sometimes a lot to homework; and automatically opting for the cheap product, as we are all inclined to do, is often not the best path to take.
My run on high E doses (only 1400IU) resulted in extended stays on the can. High E produces a remarkably viscous and resilient stool.
Even though I was knocking down my reading list, I stopped simply for that reason.
I think you are right on this.
I have been taking 800 iu of vitamin E for over 20 years (raised it to 1400 several years ago) I am healthy thus far so I don't have any ill effects from it so I assume I have good effects from taking it. I do take it with 1000 mgs of Vitamin C so I believe they work together to do well.
I'll be 77 in November and I don't look it or act like it so I believe all the supplements I take have helped me over the years. Like I said, I don't have any problems so its difficult to tell what is helping me and if they are doing what they are advertised to do. I know I am not going to stop taking them.
In case I forget, Happy Birthday! :-)
Like I said, I don't have any problems so its difficult to tell what is helping me and if they are doing what they are advertised to do.
That's being realistic. You can't know if the supplements are helping but there is no sign they are hurting.
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