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Medicine

Study: Some Antioxidants Could Increase Cancer Rates 117

sciencehabit writes "Many people take vitamins such as A, E, and C thinking that their antioxidant properties will ward off cancer. But some clinical trials have suggested that such antioxidants, which sop up DNA-damaging molecules called free radicals, have the opposite effect and raise cancer risk in certain people. Now, in a provocative study that raises unsettling questions about the widespread use of vitamin supplements, Swedish researchers have showed that moderate doses of two widely used antioxidants spur the growth of early lung tumors in mice."
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Study: Some Antioxidants Could Increase Cancer Rates

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  • Not very surprising. (Score:5, Informative)

    by Ihlosi ( 895663 ) on Thursday January 30, 2014 @04:03AM (#46108073)
    Oxidizing compounds (like H2O2) are one of the forms of "ammunition" the immune system has. Too many antioxidants in the body will make this weapon less effective.

    Also, cancer cells are more susceptive to oxidative damage due to their generally higher cell division rate. This is also why ionizing radiation usually damages cancer cells more than regular cells.

    • Probably misremembering this, but aren't cancer cells often under higher oxidative stress to begin with, too? The last thing you'd want would be to ease that pressure on them.

      • by Ihlosi ( 895663 ) on Thursday January 30, 2014 @04:36AM (#46108175)
        Probably misremembering this, but aren't cancer cells often under higher oxidative stress to begin with, too?

        They are more susceptible to oxidative damage since they spend more time in the various stages of cell division (where the DNA is especially vulnerable to oxidative damage) than regular cells (which spend most of their time not actively dividing, where their DNA is less prone to being irreparably damaged by oxidizing compounds).

        However, fast-growing cancer sometimes has the nasty habit of out-growing its network of blood vessels, creating areas of the tumor that are oxygen deprived and therefore hard to damage by using ionizing radiation.

        • by Viol8 ( 599362 )

          If the tumor is O2 deprived wouldn't that slow down cell division which would make it slow growing? I don't get it.

          • by Anonymous Coward on Thursday January 30, 2014 @06:44AM (#46108515)

            If the tumor is O2 deprived wouldn't that slow down cell division which would make it slow growing?

            Regrettably, cancer cells usually have no problem generating the energy for sustained cell divisions entirely without oxygen. They can use oxygen if it's available, but they're not dependent on it.

            http://en.wikipedia.org/wiki/Warburg_effect

          • If the tumor is O2 deprived wouldn't that slow down cell division which would make it slow growing? I don't get it.

            Yes! It's been shown that cancer cells generally die off dramatically sooner in patients who are kept in an oxygen-free environment for long periods of time.

            • It's worth mentioning that this form of "treatment" is still undergoing study, due to the currently unsatisfactory 100% mortality rate of the patients being treated.

          • Yes, in many tumors that grow too big too fast, the central region becomes necrotic (it dies). Doesn't affect things much, there are still plenty of cancer cells outside of the dying core. Some tumor therapies try to kill off the new blood vessels made by the cancer, which helps slow growth, but other therapies must be used to kill it off.

      • I skimmed the actual paper yesterday, and this seems to be exactly what they think the problem is. Normally, tumor cells accumulate DNA damage, much of it oxidative, and that damage turns on certain pathways that lead to cell death. Prevent the DNA damage from happening in the first place and that doesn't happen. This is, of course, greatly oversimplified.
    • by fuzzyfuzzyfungus ( 1223518 ) on Thursday January 30, 2014 @04:13AM (#46108127) Journal
      I think people labor under the delusion that 'health' is some sort of idyllic state of bodily perfection, rather than the state where most of the potentially catastrophic pathogens, precancerous cells, and who knows what else are being held in enough of a stalemate that something else will probably kill you first.

      In the totally contra-factual world where your body exists in edenic good health until malign external influences crop up, tamping down a dangerous-but-effective system seems like a much better idea.
      • rather than the state where most of the potentially catastrophic pathogens, precancerous cells, and who knows what else are being held in enough of a stalemate that something else will probably kill you first.

        Doctor __ : Mr. Burns, I'm afraid you are the sickest man in the United States. You have everything.
        Mr. Burns : You mean I have pneumonia?
        Doctor __ : Yes.
        Mr. Burns : Juvenile diabetes?
        Doctor __ : Yes.
        Mr. Burns : Hysterical pregnancy?
        Doctor __ : Uh, a little bit, yes. You also have thousands of diseases that have just been discovered, in you.
        Mr. Burns : You're sure you haven't just made thousands of mistakes?
        Doctor __ : Uh, no, no, I'm afraid not.
        Mr. Burns : This sounds like bad news.
        Doctor __ : Well, you'd

      • That's simply not true. You're thinking of your body's healthy and largely harmless microbial ecosystem, which can cause problems, but only when they wind up in parts of the body they're not supposed to be or your body's ability to control them breaks down. It's not like your body is perpetually riddled with would-be tumours and flesh-eating bacteria that are held at bay only by their own contempt for each other.

      • by Rosco P. Coltrane ( 209368 ) on Thursday January 30, 2014 @05:39AM (#46108339)

        I think people labor under the delusion that 'health' is some sort of idyllic state of bodily perfection, rather than the state where most of the potentially catastrophic pathogens, precancerous cells, and who knows what else are being held in enough of a stalemate that something else will probably kill you first.

        Well that's pretty much what life itself is: it's a process that tries to fight entropy for as long as possible, but always gets overwhelmed in the end no matter what.

        I've read somewhere that people (and animals, and plants) get cancer all the time in the form of cells that have mutated or divided erroneously, but their body always manages to get rid of the misfit cells. But over time, the faulty cells get faulty in nastier ways, or become more numerous, and manage to overwhelm the immune system.

    • by Anonymous Coward

      But Dr. Oz told me 1 weird trick that personal trianers dont want me to know!
       
      TV quackery has done so much damage to how people see "health" and medicine its almost fitting that this stuff starts to come about. Making uninformed decisions about your health based on TV doctors is almost as negligent as the TV quacks who shill the stuff in the first place.

      • "TV quackery has done so much damage to how people see "health" and medicine its almost fitting that this stuff starts to come about."

        Even worse are TFAs about preliminary studies in genetically-altered mice that suggested relatively large doses of ONE antioxidant might assist cancer cells. ("Relatively large" because one of them was quoted as saying '10 times a normal diet'.")

        • by Reziac ( 43301 ) *

          "Ten times a normal diet" isn't hard to achieve with concentrates or supplements.

          BTW the obsession with cholesterol levels may also be contributing to cancer: in crude terms, cell walls are largely made of cholesterol, and if you remove it, you weaken the barrier to invasion by cancer-causing agents (viruses or whatever).

    • Yep too much of anything is bad for you. Try water intoxication or Fosters as we like to call it :)
    • ....word choice. Some antioxidants are good killers of cancer cells, and some aren't. Like various chemotherapies, you need to know which ones in which combinations and dosages work, and which don't, for a particular cancer.

      Been there, done that, works well. This article just sounds like another pharma shill attack on supplements.
      • Name one antioxidant that has been shown to be effective against a cancer.

        • A trivial case is folinic acid, aka leucovorin, which is used with 5 flourouracil as the 5FU-LV pair and with third and fourth adjuvants. Old hat. Note: common folic acid is an oxidized precursor of folinic acid.

          "Show" is a relative term to the level of evidence. Your tone implies you are looking for grade A evidence, with multiple multimillion dollar trials. There are a lot of lower level evidence cases and what is more important is the individual case. Extensive individualized lab work is already d
  • by Anonymous Coward

    Most study's only find what they want/paid to find. The question now is who is correct? We are told to trust scientists that they are objective and unwilling to compromise ethic's for money. Well now what?

    • Replicate studies if you don't trust them.

    • Re:Trust me? (Score:5, Informative)

      by gnoshi ( 314933 ) on Thursday January 30, 2014 @07:53AM (#46108751)

      Well, since this is consistent with findings of previous studies which were not specifically looking for this - for example, a Vitamin E supplement trial which was called off early due to the high cancer rates in the active drug group (http://www.cancer.org/cancer/news/news/major-study-of-supplements-and-prostate-cancer-halted) - I'd say that this result is correct.
      Of course, maybe that researcher was on the take too, right?

      • Yes I have read about studies about Vitamin E causing cancer years ago. Saying the same applies to other antioxidants vitamins though is premature and makes little sense. From my own personal experiences with Vitamin E supplements I can tell you I did not like taking it. It makes me shed skin way too fast for my taste.

  • I did read anywhere in the article that taking vitamin E makes you die younger. This is more like the contraceptive pill argument. If you think you are susceptible to certain cancers, avoid. Otherwise, the benefits may be worth it.

  • Antioxidents are an interesting idea. A whole industry has built up around their healthy properties. However, it transpired that the only evidence of their efficacy was adding various compounds to cells in a petri dish. There was no evidence any of this actually worked when swallowed and ingested. Some further research was done recently and could find no evidence that taking these products actually had any affect at all on reducing your chances of getting cancer. For citation purposes, check http://www.dcsc [dcscience.net]
  • Why supplements? (Score:5, Interesting)

    by daem0n1x ( 748565 ) on Thursday January 30, 2014 @06:01AM (#46108393)

    Supplements are just one more useless thing that businesses convince people they need. The only ones that need them are businesses, to make shitloads of money.

    If you have a varied and balanced diet and don't suffer from any condition that makes you need a reinforced dose of any particular nutrient, you don't need any dietary supplements.

    Eat properly and exercise! It's easier, cheaper, and it works.

    • If you have a varied and balanced diet and don't suffer from any condition that makes you need a reinforced dose of any particular nutrient, you don't need any dietary supplements.

      So you're saying that people who don't need dietary supplements don't need dietary supplements.

      Brilliant insight there.

      • Dietary supplements are mostly marketed to people who don't need them.

        I can't tell you how many times I had to put up with people reciting me the same bullshit: "an apple today contains a lot less nutrients than 20 years ago, if you don't take these pills everyday, you'll suffer from vitamin and mineral deficiency, blah, blah, blah".

    • by Reziac ( 43301 ) *

      It doesn't hurt, and may help, to take a low-dose, balanced supplement to cover the holes in your diet. But the public sees that as "if some is good, more is better, and a whole shitload would be great!"

      Some financial facts about vitamin/mineral supplements:

      Some years ago someone tried to sell me a supplement package priced at about $80/month. Now, I've formulated animal feeds and bought supplements at the bulk level, so I know what the real cost of their product's ingredients are -- I worked it out as abou

  • by Anonymous Coward

    we can keep it.. there are a variety of ways to clean us up including a spiritual metox drift. poopooing stuff that is innocuous at worst is the new corepirate nazi mindphucking funneling system aka one brand of oranges is more than enough for us unchosens

    hang on to your hemisheres we're firing all of our guns at once trying to reach crown royal escape velocity (most linked link in history) http://www.globalresearch.ca/weather-warfare-beware-the-us-military-s-experiments-with-climatic-warfare/7561

  • Stop! (Score:2, Funny)

    by Murdoch5 ( 1563847 )
    Everything today will increase your risk of getting cancer, if you tried to live life on a diet that had the least risk of cancer causing agents you would have to starve yourself. Sure maybe this study is right and taking vitamins could increase your risk of cancer but honestly if it wasn't vitamins it could be anything else. Just keep living the life you're living and don't worry about something as stupid as if you took your vitamin A today or not.
    • Re:Stop! (Score:4, Funny)

      by ledow ( 319597 ) on Thursday January 30, 2014 @08:01AM (#46108793) Homepage

      If you're eating in any way sensibly, you should have no need of extraneous vitamin supplements anyway.

      There are certain conditions (either genetic or self-imposed, like veganism) where you don't get all that's required - and then you need to get a nutritionist on the case, not just buy things in dosages you have no clue of and take 100% RDA of on top of your normal diet.

      It's an RDA for a reason. Not only is it a suggested (not absolute) minimum, but also a suggested maximum too. People miss the fact that anything other that can potentially be damaging (there's not been much study into it, but if X amount of a certain vitamin shows that you're healthiest and "plateaus" around that usage, why would you need to take more?) in the same way as lack of it.

      And, with stuff like vitamins, it's not instantaneous results, so you can't correlate it with whether you feel better or not or got sick or not directly. In the same way that it will take you time to notice you don't have enough (say) iron in your diet, it might take you longer to notice that you have too much.

      Your body is a machine that's honed by evolution. Eat well, eat properly, eat what it has evolved to eat (which includes meat!) and the amount it has evolved to cope with. And then you'll be fine.

      • eat what it has evolved to eat (which includes meat!)

        Actually, it's possible to eat well enough on a purely vegan diet, it's just that most vegans don't do that. You just need to focus on eating protein and B-vitamin rich plants like beans and kale.

        Michael Pollan boiled it down to 3 ridiculously simple rules that I've found work well enough for all practical purposes:
        1. Eat food (by which he means things that your great-grandmother would recognize as something you'd want to eat)
        2. Not too much (for obvious reasons)
        3. Mostly plants (that seems to be what we're

        • by Reziac ( 43301 ) *

          Except that most of the plants we eat today didn't exist in that form until the advent of farming, and most didn't reach the size and yield we see today until the past 100 years or so.

          Try living off wild grains. You'll spend your entire day gathering and chewing (and will wear your teeth down to the gums) and still won't get enough to eat... and it's only available for a couple months of the year (the ripening season in late summer). And wild grain is tiny; it takes from 20 to 200 wild grains to equal one m

    • Just keep living the life you're living and don't worry about something as stupid as if you took your vitamin A today or not.

      That reminds me, I forgot to take my vitamin A today. Thanks!

  • by Maury Markowitz ( 452832 ) on Thursday January 30, 2014 @08:18AM (#46108875) Homepage

    "Now, in a provocative study that raises unsettling questions about the widespread use of vitamin supplements"

    I believe that should be worded, "Now *another* provocative study" After all, there's been a continuous stream of these. For whatever reason, the human body doesn't like being dosed with massive amounts of chemically reactive substances, gee, what a surprise.

    You can get the same dose from eating fruit, but that has no known downsides in multiple studies. If you're worried about your health, eat your fruit and veg - like they've been saying forever,

  • by Nightlight3 ( 248096 ) on Thursday January 30, 2014 @09:42AM (#46109739)

    This is a common sleight of hand in the pharma (or general 'sickness industry') sponsored mercenary pseudo-science, when they want to "prove" that inexpensive, non-patentable substance X which is actually good for you, "causes" cancer -- they give X to mice bred specifically to develop cancers they wish to blame on X. After the coarse grained form of the "discovery" story is retold in mass media (or on Slashdot), it becomes "X causes cancer."

    To see exactly how this sleight of hand works, consider substance X that improves circulation and promotes growth and vitality of blood vessels (e.g. gingko biloba, arganine, etc), which are all the effects normally good for you. But if you get a cancer, then cancer will use the improved blood supplies and stronger angiogenesis to feed itself, hence it will grow faster than if you had poor circulation and suppressed angiogenesis. That is then twisted to declare "X causes cancer." In fact the cancer was caused by the genes that were deliberately bred into this type mice.

    More generally, onset of cancer turns values upside down -- what was good for you when you were healthy, becomes bad for you when you get cancer, since cancer will co-opt it for its own growth. What was bad for you (poor circulation, cellular toxins and pro-oxidants, heavy metals, chemo, etc) becomes good for you, since it may affect cancerous cells more than the non-cancerous cells.

    A useful analogy illustrating the nature of this reversal of values in cancer, is to consider human society as a (super-)organism, which it is in many ways. In a peacetime, roads and other transport systems are good for the social organism. But in the case of war, the good transport systems often becomes a major downside since the enemy can use those roads to advance its troops and boost supply lines. In contrast, poor transportation in peacetime is bad for the social organism (backward nations). But it is also bad for the potential enemy during war. This can be easily observed on historical examples, such as WWII, where German blitzkrieg conquered the more developed nations, such as France, Netherlands, Poland very quickly, while it got bogged down in the backwards Balkans, with lots of mountains and few roads, and never really had control of those territories (except for the major cities, which were few in numbers). Similarly, in more recent wars, the backwards, mountainous undeveloped Afghanistan (or jungles of Vietnam) is practically impossible to conquer, while the more developed Iraq was overrun in weeks.

    Hence, the above style of mercenary "science" using cancer mice to "prove" alleged carcinogenicity of wholesome Vitamin C or E is analogous to mislabeling transport systems and other infrastructure as a national weakness, and advocating going back to stone age, by demonstrating how much quicker the nation can be conquered if their infrastructure is good.

    It is also similar to policies which mislabel personal liberty and privacy as harmful and deadly, by showing how terrorists (or drug dealers, crazies, etc) can take advantage of those liberties and privacy to cause harm. These are all the same kind of scams as the above "study" scaring people away from the vitamins C and E. All of such scare campaigns are often promoted by the very same people from the same crony front groups/NGOs, as result of natural synergies of interests -- a need to condition and herd the sheep with common scare tactics.

    I actually find these kinds of "studies" quite useful, since they help me identify what is good for me -- it is always the stuff that the sickness industry is trying to scare me away from (e.g. fat, meat, eggs, bacon, cholesterol, tobacco and other ancient medicinal/entheogenic plants, etc). Further, as a rule the greater the efforts and lengths they go to with their scare mongering about X, the better X must be for me (i.e. worst for their profits). The most useful one for my health was when it dawned on me to invert "make sure have the regular medical checku

  • As long as nobody comes and tells me that dark chocolate is bad for me, I will keep an open mind. But if they dare........ I'm plugging my ears shut and listening to nobody.

  • they are called whole foods for a reason. The sugar in fruit is just as bad as any sugar, unless you counter it with the fiber from the fruit. Table salt is made of two compounds, either of which is deadly on its own. Coca leaves cause very few health problems, even with chronic use. We informed potheads also get very grumpy when a study blasts marijuana using results obtained by dosing subjects with huge amounts of synthetic THC.

    Hippies and "natural foods" folks are easy to mock, but they have a point --

Top Ten Things Overheard At The ANSI C Draft Committee Meetings: (10) Sorry, but that's too useful.

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