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Last year, we all knew that ingesting antioxidants like Vitamin E was helpful for minimizing cancer risks. This year?
Hey, look! It's the new consensus! Which is the exact opposite of the old consensus! Michael Crichton noticed, too:
Crichton's point is really about how to decide scientific questions, with particular regard to global warming -- not antioxidants. So is mine. Looking back, I suspect a lot of scientists are going to laugh, just as they have a hundred times before, that we could all have been so stupid. Yet it's the belief that we're "smarter than that" which allows us to make these same mistakes time and time again. Which is the exact opposite of the old consensus! To the media, perhaps. But not to someone actually reading the literature this stuff is based on. In response to oxidative stressors, vitamin E can decrease biomarkers of lipid peroxidation, is itself killed, and requires optimal vitamin C status to function most effectively.source Unfortunately, many journalists covering scientific topics don't actually understand their subject matter. Even a fair number of doctors probably have some trouble making sense of these kinds of things. Posted by: Ryan W. on April 4, 2007 03:23 AM I'd like to add a little more context here; Vitamin C is absorbed using the same sodium mediated channel as gluocose. Elevated glucose, whether in the intestines or in the bloodstream, will inhibit the uptake of Vitamin C. And who has chronically elevated glucose? Why, diabetics, of course! source And it's been shown that ascorbate supplimentation reduces some of the scurvy-like symptoms of diabetes link So the cited study in the OP fits pretty well with the available evidence; Vitamin E is part of a system with Vitamin C, and C regenerates E. Antioxidants can potentially act as pro-oxidants if they're not quenched by water soluable anti-oxidants. Raising your fat-soluable anti-oxidants without also raising your Vitamin C intake is understandably dangerous. Diabetics are vitamin C deficient, due to their condition. So they'll be hardest hit by a raise in Vitamin E without a concurrant raise in Vitamin C or some other water-soluable anti-oxidant. Posted by: Ryan W. on April 4, 2007 03:51 AM I, for one, welcome our new consensus overlords. To misquote the Who, "... same as the old consensus overlords!" Though I think that doesn't fit the meter quite as well. :-)
This also would appear to be like global warming, where the alleged "consensus" dissolves somewhat (more or less, depending on the specific question), and one learns ins and outs of the "computer models" which generally produce the dire predictions (and non-dire ones, too, but you don't hear of those, since they tweak and re-run until the desired direness is obtained -- see Sagan's "nuclear winter" for a classic). But, regarding antioxidants: I suspected as much -- it was clear there was data missing, but, like most people, I don't have the time to dig into it. (Maybe we should have specialized groups of people -- let's call 'em "journalists", perhaps -- who could do that for us, and then write up the results? ;-)) So it seems the issue is with megadoses (of all antioxidants, or just fat-soluable ones? or is there any other kind?) in the absence of adequate vitamin C? Thanks for the clarification, Ryan! Posted by: Tim (Random Observations) on April 4, 2007 12:11 PM Sure thing! Yeah, it'd be nice if journalists were actually required to have scientific backgrounds to write on scientific topics. Their error rate is phenomenol. Um... going off the top of my head, I know that there are some problems with supplimenting with fat soluable antioxidants in conditions where there aren't enough water soluable antioxidants. For example, smokers supplementing with Beta Carotine had problems, essentially because smoking depletes the amount of vitamin C in your blood. On a side note, some artificial forms of fat soluable anti-oxidants are harmful as well. For example, natural vitamin E is D-Tocopherol. The "D" indicates that the molecule has 'handedness.' In the same way that a left handed glove won't fit on your right hand, some organic molecules are 'left handed' or 'right handed' and can have radically different effects, biologically, compared to their twins. The most discussed and possibly most important type of Vitamin E is Alpha tocopherol, though four different kinds of D-tocopherol are found in nature. There are also four different types of d-tocotrienols which are also, for whatever reasons, considered 'vitamin E'. Synthetic Vitamin E, on the other hand, is DL Alpha tocopherol, or a mix of 'left handed' and 'right handed' molecules. Taking in more left handed tocopherol can reduce the amount of the other, useful, forms of vitamin E in your body. Generally speaking, synthetic production of vitamins often produces mixes of D and L configurations for various molecules, while plants and animals tend to produce a single configuration. All our amino acids are of the L configuration, for instance. That's why it's crucial that your Vitamin E, Beta Carotene and certain other vitamins, are from a natural source. I mention this because earlier studies, using both left and right handed fat soluable antioxidants (vitamin E and maybe beta carotine as well) showed people having health problems due to supplementation. If you read an older study on anti-oxidants, make sure to note whether natural or synthetic antioxidants are used. So it seems the issue is with megadoses (of all antioxidants, or just fat-soluable ones? or is there any other kind?) in the absence of adequate vitamin C? Antioxidants can be fat soluable or water soluable. Water soluble anti-oxidants tend to get washed out of the body very quickly (3-4 hours) and megadoses of water soluable vitamins need to be given on a regular schedule through the day because of this. But they're crucial, as you mentioned. Adding in a little Vitamin B complex, about 25% of the USRDA several times daily, seems to help me and is popularly reccomended, though I haven't read up on the biological role of the B vitamins yet. There are a number of water soluble antioxidants. Obviously, if you get them from diet you don't want them oxidized (cooked in the presence of oxygen.) Vitamin C (ascorbate) and Citric acid both come to mind. Ascorbate seems to be one of the best and certainly one of the most studied, and has other useful functions such as being the limiting factor in collagen formation (which a number of diseases deliberately destroy.) While ascorbate's role in collagen formation is often ignored by the alternative medicine crowd, I personally believe that it's hugely important (i.e. not all of ascorbate's benefits are due to it's function as an antioxidant) and could support this point if you want. Incidentally, if you do supplement with Vitamin C you might be better off using mixed acid-neutral ascorbates (ascorbate salts such as magnesium ascorbate, potasium ascorbate, calcium ascorbate, zinc ascorbate) since they're more readily absorbed and too much acidic vitamin C doesn't seem to be healthy. I tried taking megadoses of acidic vitamin C (ascorbic acid) and while it was helpful, I also got small mouth ulcers. Acid-neutral vitamin C doesn't have that problem. There are a lot of claims that bioflavanoids such as hesperidin or rutin 'complex' with vitamin C in the body and somehow improve it's function but I've tried taking these in pill form with C and noticed no improved effect. A person's vitamin C needs vary wildly depending on their health. The current US reccomended daily allowance is based on the amount of Vitamin C required to prevent scurvy. It's pretty low compared to the amount your body can actually use and may actually need. Good health to ya! Posted by: Ryan on April 4, 2007 03:41 PM To put things more simply; Ascorbate salts (acid neutral vitamin C) - good Ascorbic acid - okay in small doses. Bad for megadosing. Beta carotine and Vitamin E - only from natural sources and only with vitamin C. Getting enough ascorbate is more important than getting enough fat soluable anti-oxidants. Fat soluable anti-oxidants can be regenerated by your body as long as you have plenty of Vitamin C. The B vitamins play some role in this process, but I can't remember what, offhand. Posted by: Ryan W. on April 4, 2007 06:25 PM BTW... I don't know whether or not other water soluable anti-oxidants like citric acid or EGCG from green tea (which is touted as a stronger anti-oxidant than Vitamin C) could take the place of Vitamin C for the purpose of regenerating vitamin E or Beta Carotine. It's a good question. I'll look into it in about a week if I have more time then. Posted by: Ryan on April 5, 2007 02:59 PM Their error rate is phenomenol. I don't usually point out spelling errors, but that was just too funny to pass up. :-)
I was begining to get the suspicion that most the supplements people take might not be quite what they're expecting. Sounds like that might have been right in some cases. Are these kinds of details on the label? I don't recall seeing such. I'm impressed by your depth here, Ryan. And you can't get a job in this area these days? Don't mean to pry, just curious. And I've been drinking a bit of green tea lately, so it's interesting that you'd bring that up. Posted by: Tim (Random Observations) on April 6, 2007 12:20 AM All things in moderation. Posted by: rara on April 6, 2007 07:29 PM Are these kinds of details on the label? I don't recall seeing such. Yes, usually they are. The non-natural suppliments will often be labeled as dl-tocopherol in very small print somewhere on the label. I've asked my parents to throw out at least one bottle because of that. Likewise, those vitamins which are from natural sources will say "from natural sources." Since natural E is usually a little bit more expensive than the non-natural kind, it's to the benefit of companies selling it to advertise the fact, and they typically do. I'm impressed by your depth here, Ryan. And you can't get a job in this area these days? Don't mean to pry, just curious. Thanks. :) To be honest, I've never much tried. My goal had been to work in biotech. I'm good with concepts but, frankly, terrible with labwork. Touch the pipette full of ether and it volatilizes and sprays your contents on the counter top. Gram stains should be purple or pink but the way I heat fixed them, they turned out black. And so on. Computers seemed a useful avenue to get into the industry without having to touch any test tubes. I'd wanted to take an extra year of college but my dad was insistant that I should just jump into the workforce (back during the tech boom) even though I had very few skills. I should just learn on the job. I managed to pick up a little bit about database design and high level scripting languages, particularly actionscript, but the one class I took in Java didn't make me feel comfortable that I knew enough to do productive work in that area. I'm still tremendously interested in health-related topics and infectious diseases. I did some volunteer and paid work for the local arboretum back in Illinois including an internship with a taxonomist, and I'm pretty decent in terms of my understanding of herbal medicine. Maybe I could get a job related to that. I'm not sure it would pay as much as computer work would. Maybe I should look again, since I have a better skillset than I did in the past. My dad's suggested it on more than one occasion. I did send out a resume to Abbott labs after college, and one or two other places. But i didn't do the test-tube cleaning jobs while in college that would get me into a lab and have that experience to back me up, so I assume that that hurt me. And also I was tremendously more persistant in regards to my tech career. After all, biotech is certainly going to be reliant on computers. But I really have no idea where I'll end up. And to be honest, I tend to be rather unfocused. Regarding green tea - Green tea leaves have one of the highest concentrations of oxalic acid, which some have speculated is bad in large quantities. 10% of kidney stones are formed of oxylates, or oxalic acid which becomes an insoluable oxylate in the kidneys and cannot be excreted. (though it's debated whether some other type of predisposition might have a greater impact here than raw oxylate intake) Ascorbate, despite it's tremendous benefits, seems to have the odd effect of increasing the body's oxalic acid uptake, which may be a bad thing. One interesting tidbit where the practices of a culture actually have an intersting health benefit; when I was in China milk tea was a common drink. And the calcium in the milk should react with the oxalic acid in the heated tea, forming calcium oxylate, which is insoluable and which your body would not absorb. It's always interesting when a culture develops what seems like a solution to a problem most people in the culture didn't even know existed. Maybe it's just a coincidence. I don't know. Cheers, Ryan Posted by: Ryan W on April 7, 2007 04:06 PM btw. Ascorbate, Vitamin E and SOD (superoxide dismutase, which is made from small quantities of selenium) work synergistically. I was unsure how other antioxidants like green tea extract affected these. Most experiments seem to say that green tea has no effect on those antioxidants. One study found a slightly elevated level of vitamin E due to green tea extract. Plasma concentrations of lipids, ascorbate, alpha-tocopherol, and lipid peroxides did not change before and after the experiment in either group, but beta-carotene was higher in the tea group link
So as healthy as green tea is, it doesn't seem to be a substitute for the ascorbate, vitamin E, SOD triangle. Posted by: Ryan W. on April 13, 2007 08:02 AM So as healthy as green tea is, it doesn't seem to be a substitute for the ascorbate, vitamin E, SOD triangle... Which does... um, what again? And where does one obtain SOD? Posted by: Tim (Random Observations) on April 13, 2007 11:32 AM Which does... um, what again? Sorry. I'll try and be clearer. Vitamin C and vitamin E work together. It's bad to have lots of vitamin E without enough Vitamin C to protect it. That's what the research in your original post showed, except the reporter didn't seem to quite understand it. I was trying to figure out how effective green tea was at doing one of vitamin C's jobs, namely; protecting vitamin E. It turns out green tea is not good for that particular function. So while green tea is healthy, you still might need vitamin C suppliments if; since all these things lower the level of vitamin C in your blood. The links I dug up show that green tea, for all its benefits, works an antioxidant in a So no matter how much green tea you drink, you'll still need vitamin C as an antioxidant. Vitamin C is more than just an antioxidant, of course. It has other funcitons as well. But I'm trying to keep things simple by focusing on Vitamin C's role of protecting vitamin E. Regarding Superoxide Dismutase (SOD) a powerful antioxidant; here's some cites which hopefully will answer your question.
SOD 1 but not SOD 2 expression was enhanced 2–4-fold in selenium supplemented cell cultureslink http://en.wikipedia.org/wiki/Superoxide_dismutase"> SOD wiki link SOD is probably destroyed by the digestive process if taken directly as a suppliment. Posted by: Ryan W. on April 13, 2007 03:00 PM Vitamin E and Superoxide Dismutase seem to work together with vitamin E increasing the activity of SOD. Posted by: Ryan W. on April 13, 2007 03:07 PM Just got this. Thought I'd post. I didn't know much about Selenium supplimentation and this seems to warn against it since it's too easy to overdose. Seems better to stick with ascorbate (which doesn't cause lasting problems, even if you get way too much). Dear Dr. Mirkin: Should I take selenium supplements? Posted by: Ryan W. on August 9, 2007 08:57 PM Thank you, Ryan! I'll have to check my multi-vitamins for selenium levels. Well, or should if I ever decide to start taking them consistently. Posted by: Tim (Random Observations) on August 10, 2007 11:46 AM I got some new information and wanted to follow up here regarding vitamin E and heart attacks. Previously, I had only considered vitamin E as an antioxidant and not looked into its other effects. I need to do a little more research on this topic since the studies I can find don't differentiate between natural and artificial vitamin E, which is critical. However I wanted to post before I forgot. It seems that Vitamin E might be a Vitamin K antagonist of some kind. Vitamin K antagonists seem to have a rather paradoxical effect, so it's not surprising that a large portion of the medical community seems confused about them. In the short term, they thin the blood. However Vitamin K, particularly K2 (menaquinones) from bacteria as opposed to plant sourced K1, seems crucial to preventing arterial calcification in the mid to long term. So the long term effect of anything that interferess with vitamin K is to promote arterial calcification and the calcification of soft tissue leading to more heart attacks, despite the fact that in the short term it can successfully treat them. This applies, also, to a variety of other drugs still considered blood thinners such as warfarin, aspirin and other salyciliates. Also, the current trend towards vitamin D (better called "hormone D") supplementation would lead towards arterial calcification and calcification of soft tissue if the person taking it didn't have enough vitamin K2. The predominant medical view seems to be that hormone D promotes healthy bones. But without vitamin K, the extra calcium from hormone D leads to calcification of tissue rather than stronger bones. Fortunately, it seems like menaquinone (Vitamin K from certain bacteria) does a great job of not just preventing but actually reversing arterial calcification. I'll try to source this better later. Posted by: Ryan W. on August 12, 2008 02:30 AM hmm... it turns out that natural alpha tocopherol can, in fact, interfere with Vitamin K metabolism. Very interesting. Sorry for my much earlier posting then. There had been a whole rash of studies showing various negative effects from antioxidants when artificial varieties were used. The problems disappeared when natural antioxidants were used. And I assumed the OP was part of that deluge. But maybe Vit. E's effects could be explained by its interactions with Vit. K. A while ago, Dr. Andrew Weil was touting Turmeric as a life-extending product. With the Japanese diet high in Menaquinone from their fermeted foods, that might work. But without the particular fermented foods the Japanese eat, it could do more harm to people than good. It's strange how many supplements touted for life extension, including those which reduce mortality for several years out, can also lead to arterial calcification.
Warfarin-induced artery calcification is accelerated by growth and vitamin D. The following from link Vitamin K in the treatment and prevention of osteoporosis and arterial calcification. from link Arterial calcification, a process of hardening of the arteries, may be inhibited and even reversed with supplementation with high-dose vitamin K, suggests an animal study. The following from link Dietary Intake of Menaquinone Is Associated with a Reduced Risk of Coronary Heart Disease: The Rotterdam Study The following from link The coumadin in Turmeric is anti-inflammatory, anti-viral, anti-bacterial, anti-oxidant as well as having other properties. Posted by: Ryan W. on August 12, 2008 04:50 PM There had been a whole rash of studies showing various negative effects from antioxidants when artificial varieties were used. Reminds me of the findings regarding "hormone replacement therapy" in women. It was supposed to be awful. Only what was being tested was an artificial version of estrogen, with a different behavior, not the real thing. (If there *have* been studies on real estrogen, let me know. Otherwise...) Now women, medical professionals, and journalists have been thoroughly indoctrinated to believe it's a bad idea, and the real thing may not be tried. Posted by: Tim (Random Observations) on August 13, 2008 07:52 PM Only what was being tested was an artificial version of estrogen, with a different behavior, not the real thing. Interesting. Do you remember if this was in reference to Premarin? That's natural "conjugated" estrogen (Estrone) from pregnant mares urine (thus 'Premarin,' though why they'd use a trade name that emphasized such an origin is beyond me) They've used that for a while. People seem to have the impression that it was overproscribed a few years back. Or are you referring to something different? I'll keep an eye out. Posted by: Ryan W. on August 14, 2008 05:59 PM Hmm. Came across this;
The site was very much against PemPro and Provera (artificial progesterone) and lukewarm to negative on Premarin. Written in 2006, it comments about a lack of large scale studies at that time; .Why haven’t there been large studies of bio-identical estrogens and progesterone? The reason is: bio-identical hormones occur naturally in the human female and cannot be patented. There is no economic motivation for the large pharmaceutical companies to finance a study using bio-identical estrogens and progesterone. We hope a study will be done someday. Posted by: Ryan W. on August 22, 2008 09:58 AM Add your two cents...
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I, for one, welcome our new consensus overlords.
Unfortunately, what people don't understand is that reality can not be voted upon. This is the same kind of sick and twisted logic that went into The Jesus Seminar. "If we experts all cast votes, maybe we can figure out what is true!" Unfortunately, what you'd probably find is that upon sampling the consensus of the experts on a given issue throughout history, you'd find a wavy, insane line.
And, to sum it up in one word: Phrenology.
Posted by: Michael Zappe on April 3, 2007 10:17 PM