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Canada Medicine Science

Free Radicals May Not Be Cause of Aging 371

An anonymous reader writes "Researchers at McGill University in Montreal have uncovered strong new evidence that that wildly-accepted mitochondrial free radical theory of aging (MFRTA) is wrong. MFRTA suggests that free radicals cause oxidative damage, which in turn leads to the aging process. This new evidence shows that high levels of Reactive Oxidative species are rather a biological signal used to combat aging then the process itself. This goes against claims of major health benefits from consuming foods and particularly supplements that contain antioxidants."
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Free Radicals May Not Be Cause of Aging

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  • Then... (Score:4, Funny)

    by fyngyrz ( 762201 ) on Sunday December 19, 2010 @11:34AM (#34607758) Homepage Journal

    Jailing the radicals was good?

  • I mean, how can anything with the word free right there as part of it's name be bad for you?
    Like, free porn, or free t-shirts and free guns. So obvious.

  • by wisebabo ( 638845 ) on Sunday December 19, 2010 @11:45AM (#34607844) Journal

    If free radicals were responsible for (a large part) of aging then blueberry farmers would routinely live to be more than 100. Blueberries supposedly have the highest amount of anti-oxidants (by weight? volume? serving size?) of any food.

    Too bad, I love blueberries.

    • Actually, the Acai Berries has twice the amount of Anti-oxidants than blueberries.

      • Black coffee, espresso in particular, is also very high in anti-oxidants. Too bad all that coffee wont help...

    • Occam's razor... (Score:5, Insightful)

      by Joce640k ( 829181 ) on Sunday December 19, 2010 @12:16PM (#34608136) Homepage

      If ANY diet made you live significantly longer we'd have noticed by now.

      Same goes for exercise regimes, eg. If running five miles a day made you live longer we'd have noticed.

      We can point to plenty of things that make your life shorter, eg. smoking, eating nothing but junk food, but I'm fairly sure that if you're living a reasonable lifestyle then genetics completely dominates. After that it's probably as much down to happiness as anything else.

      • It is pretty widely understood that a calorie-restricted diet (something like 30% fewer calories than the RDA, for humans) makes *any* animal live significantly longer and with fewer health problems. It's worked for everything it's been tested on. There have been some short-term studies on humans, but I'm not sure if there are any long-term ones.

        But 'eat so much less that you're always hungry' is not an acceptable diet plan. We all just want to eat something *extra*, or take a pill, to fix it. I know I ca
        • This doesn't apply to people that are starving or otherwise malnourished. This is assuming a *balanced* calorie restricted diet. You still need the fats, proteins, carbs, vitamins, minerals. Just fewer calories.
        • Re:Occam's razor... (Score:5, Interesting)

          by Joce640k ( 829181 ) on Sunday December 19, 2010 @01:21PM (#34608638) Homepage

          I don't know all the answers to salorie restriction but it's been known about since 1934. Nearly 80 years is enough time to find out if it works in humans but I'm not aware of any practitioners living extra-long lives (and there's been plenty of people who tried it...)

          If you plot a graph of size vs. lifespan in mammals it forms a fairly straight line. See here [senescence.info]. Humans already live much longer than the graph predicts (we're the dot marked "HS" on that graph) and we're not sure why. Maybe there's a connection. Maybe that's why calorie restriction doesn't work on humans because we're already a long way above the line.

          • by HiThere ( 15173 )

            It's not the sort of diet that you can stick to of your own free will. I'm sure that there have been short term attempts. Long term attempts...I seriously doubt it. (Note that simple starvation won't do. You've got to have properly balanced starvation. And this *does* make you more susceptible to infections and diseases, so it needs to be in healthy circumstances. Can always get warm enough, etc.)

            The limitations on this strategy are severe enough that I really doubt it could be done on/by anyone who w

          • by timothy ( 36799 ) * Works for Slashdot on Sunday December 19, 2010 @03:31PM (#34609598) Journal

            But salorie restriction is very unpopular with girlfriends, wives, heirs, etc ... ;)

            timothy

          • I don't know all the answers to salorie restriction

            (smacks forehead) wow... my boss isn't being cheap... he wants me to live longer.
      • we know of at least one that extends life,on of them is called calorie restriction: http://en.wikipedia.org/wiki/Calorie_restriction#Mortality [wikipedia.org]
        But it seems to be awful to be in starvation everyday for the rest of your long life.

        • by base3 ( 539820 )
          Whether a calorie restricted diet would make me live longer or not, I know it would seem like longer!
        • There's no evidence that it works in humans.

          It's been known about for a long time and there have been plenty of practitioners. None have lived exceptionally long lives AFAIK.

          What studies seem to suggest is that the long-term adverse effects of calorie restriction eventually catch up with the benefits and cancel them out. ie. Symptoms of aging are delayed a bit but when they arrive they're much worse.

      • by Kjella ( 173770 )

        We can point to plenty of things that make your life shorter, eg. smoking, eating nothing but junk food, but I'm fairly sure that if you're living a reasonable lifestyle then genetics completely dominates. After that it's probably as much down to happiness as anything else.

        And avoid setting off the chain reaction that'll trip a systemic collapse and kill you. Seriously, I have some elderly in my family that seem to hang on by the thread of their lives but they do it year in and year out as long as a gentle breeze doesn't knock them off their feet. Others have seemed far more healthy, but then they get hit with a bad case of the flu that a 60 year old would recover from, a 40 year old would just be off his feet a few days but an 80 year old starts getting all sorts of other pr

      • by martin-boundary ( 547041 ) on Sunday December 19, 2010 @04:10PM (#34609872)

        If ANY diet made you live significantly longer we'd have noticed by now.

        Two economists are walking down the street. One sees a hundred dollar bill lying on the pavement and bends down to pick it up. "Don't bother," says the other, "if it was real someone would have already picked it up by now."

        • Two economists are walking down the street. They see a hundred dollar bill lying on the pavement. They stand there for a while and watch several bank managers come along, pick it up, inspect it and put it down again.

          One bends down to pick it up. "Don't bother," says the other, "if it was real one of those bankers would have kept it."

    • First of all, there are a huge variety of antioxidatns. It's really stupid to compare catechins, which are hydrosoluble, and curcuminoids, which are liposoluble. Both are antioxidants, but are not comparable.

      Second: this study does not disprove the usefulness of antioxidants for preserving DNA integrity. OTOH, there are studies with evidence that anti-oxidants are effective in this sense.

    • ...then blueberry farmers would routinely live to be more than 100

      Not quite, since what the supermarket calls blueberry is not necessarily what we are talking about. The most commonly sold one is vaccinium corymbosum, which has big fruits, but not a lot of the anthocyanins that are supposed to be good for you (they are white inside, not blue all through).

      Anyway, there is evidence to suggest that aging is related to the shortening of telomeres; this is really a rather old idea, but apparently it has been gaining in strengths recently. In my view, ageing is just one of man

      • by woolio ( 927141 ) on Sunday December 19, 2010 @01:08PM (#34608554) Journal

        Haven't you noticed how people not so many years agou used to look quite old and frail already in their sixties, but now we are no longer surprised to find that people in their seventies are still physically active and mentally alert?

        Yes. Then I realize that old people haven't changed... When I was 10, people in their 40s looked aged, people in their 60s looked very old and frail, and people in their 80s looked like something from a horror movie.

        Now that I'm in my 30s, I find people in their 40s don't look so old. And people in their 60s don't look all that much different with the exception of some white/grey hair and a few more blemishes on their skin.

    • Seems like you need to read the /. post from a few days ago about the link between fertility and cell phones...

    • Too bad, I love blueberries.

      Then eat them! Blueberries are nutritious and delicious. Maybe they won't make you live forever; seriously though - what do people want from a damned fruit!

    • "Too bad, I love blueberries."

      Well,, you don't have to stop eating them. THIS JUST IN: Blueberries in high amounts cause cancer.

  • I don't think I could give up my tomatoes even if they were...

  • What would happen if they actually "cured aging". Would our system work if all the sudden people lived to 200 or 500 or... I would almost think, like that STNG episode where they all had to die at 60, maybe you would have to cap it a 100 or 150. If I could live to 100 as healthy as I am now (at 43) I would think that would be a pretty good life.
    • That is an excellent point, and one I have thought about on more than one occasion, but for different reasons. What would happen to social welfare and retirement pensions when the average person was drawing on them for 100 years, instead of 10 years? Would you have to forego Social Security payments if you "took the cure for aging"? Would only rich people be able to afford it, and then create an oppressive voting block over time in a democracy? Would you eventually just get bored with life even while yo

      • There would be tons of secondary problems come out of 'solving' the problem of aging too. For example a woman is born with all the eggs she will ovulate. Currently that's not an issue in most people as we tend to have kids around 20 or so years old, but as women push back childbirth in to the later part of their lives all kinds of issues start cropping up. Again, these issues can be over come with enough science, but as we all know that doesn't come cheap and will benefit the rich the most.

        Also, I remember

      • If most people would be able to stay reasonably healthy and with normal functional capacity for 500 years on average, then there is no reason or possibility for retirement at 60 - eternal life would naturally mean eternal work to sustain yourself, of course.

    • It would be one thing if you were healthy, 35, and live to 200 or 500. You would work and be productive. Birth control would be no more of a concern than it is now ( imo earth is already past the carrying capacity so it's just a question of critical failure in 35 years or 75 years.) Obviously, you'd need a strong tie between the immortality treatment and birth control (vasectomies for men, not sure what for women-everything we have now is invasive except iud/pill and those don't work for everyone)

      OTH, if

  • More proof my all beer diet is going to make me live forever.

  • by Toe, The ( 545098 ) on Sunday December 19, 2010 @12:03PM (#34608030)

    More generally, scientists should not confuse cause and effect. Or even more generally: correlation for causation. That's just bad science.

    And yet, it seems to be rather prevalent. Especially in the questionable science of nutrition, where any slightly new idea can lead to a fortune in book sales, diet plans, drug development, etc.

    • Well to be fair, confusing cause and effect is terrifically easy in science, as is confusing correlation and causation. For the most part, science can only discover correlation, and assigning causation requires a sort of intellectual leap.

      And all the fad diets and the industries built around them-- the problem there isn't "bad science". It's really a couple of bad things that happen regardless of how good the science is. First, you have bad news reporting. A single study comes out that suggests some sm

    • More generally, scientists should not confuse cause and effect. Or even more generally: correlation for causation. That's just bad science.

      And yet, it seems to be rather prevalent. Especially in the questionable science of nutrition, where any slightly new idea can lead to a fortune in book sales, diet plans, drug development, etc.

      Has a scientist ever told you to eat more antioxidants so you'd live longer? My gut tells me scientists are smarter than the people you actually hear this stuff from.
      It's one thing to say X seems to have effect on Y in your body, and another to say doing X will make you live longer.

      CA:
      It's like blaming mechanics for the notion that changing your oil more frequently makes your car last longer. If you actually ask one, they'd tell you plainly, more frequently != more betterer...

  • ...Noam Chomsky *isn't* making me get older?

  • Free radicals don't cause aging, staring at Perl code does. Drives you to drink and makes you lose hair, too.
  • by St.Creed ( 853824 ) on Sunday December 19, 2010 @12:25PM (#34608214)

    As shown by this research: http://www.nature.com/news/2010/101128/full/news.2010.635.html [nature.com]

    Rather straightforward, isn't it? Why *does* a cell die, anyway? As long as it can grow and replicate, it shouldn't. Except for the telomere TTL-signal. Once we intervene in that, I think aging could be reduced or slowed drastically. I doubt there is much risk of cancer: cancer is when cells don't respond to normal apoptosis signals and keep growing. While removing the TTL-signal could be risky, I'm confident that cells with only the Time To Live removed could still respond normally to other signals. And while cancer *may* be lethal, aging is *always* lethal.

    • by mangu ( 126918 )

      I doubt there is much risk of cancer: cancer is when cells don't respond to normal apoptosis signals and keep growing.

      You don't need to remove the TTL, just reset it every fifty years or so.

      A drug that restores the telomeres in each cell could be applied when needed, and then the telomeres would be shortened again at each cell division in the normal way.

      • by base3 ( 539820 )
        And would have the advantage of having to be bought every fifty years or so. I welcome our immortal pharmaceutical overlords :).
      • by realxmp ( 518717 ) on Sunday December 19, 2010 @02:41PM (#34609218)

        You don't need to remove the TTL, just reset it every fifty years or so.

        A drug that restores the telomeres in each cell could be applied when needed, and then the telomeres would be shortened again at each cell division in the normal way.

        There exists such a chemical, it's an enzyme it's called telomerase and it is actually active in a significant proportion of cells in the body. Either way the situation is far more nucanced than just the telomeres.

  • by Goaway ( 82658 )

    Hey! Scientists! Stop ruining nonsensical old X-Files episodes!

  • "Researchers at McGill University in Montreal have uncovered strong new evidence that that wildly-accepted mitochondrial free radical theory of aging (MFRTA) is wrong.

    Next you'll be telling us midiclorians aren't responsible for our force powers either!

  • by kbolino ( 920292 ) on Sunday December 19, 2010 @12:53PM (#34608442)

    What makes a theory "wildly accepted"? Does it mean there are a bunch of scientists who gather spontaneously at impromptu bonfires and ululate their heathen belief in a carnal fashion?

  • coughs, colds, fever, and yes, even Cancer. Scientists (mostly on payrolls) claimed all of the above. Part of it was a correlation == causation. Another part was executives telling them what to say.
    Now, we have scientists that had found a correlation between aging and radicals. So, they used stats rather than hard proof to claim it. Why? Because SO MANY are in a hurry to be at the top of the heap.
    Are radicals associated with aging? It would appear to be. Are radicals the cause of aging? Well, that needs t
  • TFA doesn't say how these worms were genetically modified.
  • by fishexe ( 168879 ) on Sunday December 19, 2010 @02:03PM (#34608928) Homepage
    from TFA:

    'If you ask most people on the street what causes aging, many would say free radicals, but it's a complex story.'
    —Dr. Siegfried Hekimi, McGill University

    I'm pretty sure if you asked most people on the street what causes aging, a handful would say free radicals, while most would say time or God. Then if you followed up by asking them, "Don't you think it could be free radicals?" their answer would be "WTF are free radicals?"

  • Free Full Article (Score:5, Informative)

    by reverseengineer ( 580922 ) on Sunday December 19, 2010 @02:18PM (#34609062)
    The relevant journal article is available for free right now here [springerlink.com].

    One thing that should be pointed out is that this article is in the January 2010 issue, and was initially published online in September 2009, so this isn't breaking news, though it looks like research may have continued in the same lab following this paper- there's no reference t paraquat in the paper, for instance. Another, which is touched on in the news article is that the scientists involved do not dispute that reactive oxygen species can have deleterious effects on living organisms- just that aging is not a process of mitochondria being injured by ROS. Their conclusion spells it out:

    It is difficult to doubt that mitochondria play a key role in the aging process [67, 68]. However, although it is well documented that irreversible oxidative damage accumulates during aging [69], it seems that the MFRTA’s core statement that postulates that aging is triggered by the detrimental action of ROS produced during normal metabolism is simply wrong. It is not yet clear whether aging has a single cause or whether such a notion is misguided. In any case, the correlation between the presence of oxidative damage and the aged phenotype simply does not imply causation. Oxidative stress might be the consequence of aging, if aging indeed has some discrete cause, or causes, distinct from oxidative stress [40]. Alternatively, oxidative stress might result from the failure of one particular maintenance system of the organism and thus participate in causing aging, but no more, as is often proposed in multicausal or unifying theories of aging [3–6]. Therefore, there is no reason to believe that it could not be beneficial to health to counteract the deleterious effects induced by ROS, at least in pathological situations. However, any intervention will nonetheless have to be very critically evaluated as clearly revealed by the antioxidant supplementation trials and in light of the increasing number of studies showing the crucial roles of ROS in cellular signaling.

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