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Human Study Shows Benefits of Caloric Restriction

Continued from page 1

By Emily Singer

Tuesday, June 06, 2006
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TR: So how do they measure up?

JH: Caloric restriction has greater benefits than exercising, especially on blood pressure and inflammation.

TR: Now you are planning a new trial of caloric restriction?

JH: Yes. The CRONies study was just a cross-section. We don't know what these people were like before they started caloric restriction. In the new study, we will recruit people who are normal to slightly overweight. We'll ask them to eat 25 percent less than they ate before. The idea is to have people do this for two years, but that will be very difficult.

TR: What do you hope to show?

JH: At the end of two years, will these people have undergone the same biological changes as rats and mice on caloric restriction? We won't be able to say they will live longer, but at least we'll be able to see if the same underlying changes are taking place.

We'll also be able to determine the maximal level of caloric restriction. For all we know, CRONies are overdoing it. Maybe you can get the same benefits with a smaller decrease in calories.

TR: One question in aging research is whether scientists can design drugs that mimic the health effects of caloric restriction (see "The Fountain of Health"). Will these studies help that goal?

JH: It will give us information on the types of biomarkers we should be looking for. If a mimetic causes the same biological changes, we can say they're working like caloric restriction.

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Comments
  • Caloric Restriction
    Interesting research.  But it should be noted that such a diet increases the risk of influenza and other infectious diseases at every stage of life.  A parallel statement would be, "People who deliberately amputate both legs are far less prone to foot disease."
    Rate this comment: 12345
    Guest (Steve)
    06/06/2006
    Posts:1
    • Needed fat?
      I am an RN, and wonder if you would have many losses of life due to not being able to survive infection, trauma etc.

      My brother in law just lost eighty pounds during a lung infection complicated by a pocket of asbestos that had to be removed surgically. His doctor said he would have died without the reserve fat. He was not an obese person by normal standards.
      Rate this comment: 12345
      Guest (Ron Wagner)
      06/06/2006
      Posts:1
      • Nobody knows
        We don't even know if CRON can work in humans - or how to impliment it.  The most common theory for those practicing it: The risks of dying/suffering (e.g. from reduced reserve fat) are fewer than the risks from not doing it.  No enlightened CRONie says that it will (beyond all reasonable doubt) make them live longer.  Life is filled with risk.
        Rate this comment: 12345
        Guest (John)
        06/07/2006
        Posts:1
  • exercise
    How do these low calorie types fuel exercise. Do you have to give that up?
    Rate this comment: 12345
    Guest (Steve too)
    06/06/2006
    Posts:1
    • Nope
      CRONies exercise like everyone else: just as they choose to.  Some do zero - some run - some lift weights.  It is not a religion where you have to play by any rules - beyond reducing caloric intake
      Rate this comment: 12345
      Guest (John)
      06/07/2006
      Posts:1
      • Well...
        This is not entirely true.  Intense exercise, long distance running for example, burns lots of calories.  You couldn’t do as much on a severely calorie-restricted diet.  You simply wouldn’t maintain enough calories to live.

        This is why such aerobic exercise is both age-fighting and aging.  It improves muscle tone, cardiovascular fitness, etc.  At the same time, however, the burning of so many calories is a source of the oxidization which CRON seeks to avoid.

        The CRONies are quick to point out that consuming more calories but burning them off through an active lifestyle does not equate to calorie restriction.
        Rate this comment: 12345
        Guest (Mark)
        06/07/2006
        Posts:1
  • quality of life
    What kind of life is it that one leeds for decades. Counting all calories, never truly enjoying a meal. And why this obsession with longevity. I would rather have a fun filled life and only reach 70 than being miserable until I am 120.
    Rate this comment: 12345
    Guest (aymeric)
    06/06/2006
    Posts:1
    • Good point.
      Good point. Especially if you died of an illness at 70 years old, because you didn't have the reserve fat you needed.
      Rate this comment: 12345
      Guest (Ron Wagner)
      06/06/2006
      Posts:1
    • What is yer point?
      In America there is right to pursue happiness.  If people choose that counting calories for 120 years, they have a right to do so.  All CRONies seem to start with the attitude: "I'm going to try it - if I don't like it I can quit.
      Rate this comment: 12345
      Guest (John)
      06/07/2006
      Posts:1
    • wrong point on quality of life
      No, they don't count calories for years. The calorie count only happens in the beginning of the project, for weeks or months at most. Once you get used to the ballpark of what low calories means, it becomes second nature - you do it without thinking about it.

      As for being miserable???? You guys are NUTS!!! How about being miserable from diabetes and all its complications...and from all the other life style diseases, as well.

      As for mental capacity? Look around, and you'll see a statistical trend - obesity is inversely proportional to IQ.

      I haven't seen  a dumb skinny person, ever.
      Rate this comment: 12345
      Guest (GG)
      06/07/2006
      Posts:1
      • Quality Of Life
        It is a common statement.  "I would rather do X for X years."  One mistake is to see it as simply a longevity issue.  A vegetarian will not only, on average, live longer but be healthy longer.  A fat person's last decade or more will be painful and expensive.  I remember a quote from a vegie doctor, "We want to make it so your first heart attack is your last one as well."
        Rate this comment: 12345
        Guest (Richard)
        06/08/2006
        Posts:1
      • quality of life
        just go to west virginia...plenty of rail thin dumb hicks around...I am just amazed at this obsession with living long
        Rate this comment: 12345
        Guest (aymeric)
        06/08/2006
        Posts:1
      • i have
        "I haven't seen a dumb skinny person,ever."  Ever heard of Paris Hilton?
        Rate this comment: 12345
        Guest (devin)
        06/20/2006
        Posts:1
  • Long Life?
    Actually, my take is that for a certain class of people who perhaps work on very long term projects such as the creation of global literary systems, or projects that require a great deal of time to complete a long life could be both productive and rewarding.  For most people however I tend to think that long life would equal long misery and not be worth the effort.
    Rate this comment: 12345
    Guest (CatoTheElderII)
    06/06/2006
    Posts:1
    • I disagree and agree
      I tend to think most people love life and want it to go on for a long time.  Only a small number of people choose to die.  I agree that most people think CRON would not be worth the effort.  I think that can even be proven - given that so few people choose it
      Rate this comment: 12345
      Guest (John)
      06/07/2006
      Posts:1
  • more factors than just this
    My Granny, born in the early 1900's, ate what ever she wanted and never exercised. In old age she had type 2 diabetes and high blood pressure but she never lost a limb or went senile (she did suffer some strokes at the very end). She died peacefully at 95. Just like global worming there are a ton more factors at play here. There's no magic bullet.
    Rate this comment: 12345
    Guest (bill)
    06/06/2006
    Posts:1
    • Yes!
      Yes, there are a lot of factors at play.  There is no magic bullet or magic anything.  What CRONies believe is that your Granny might have lived even longer and not had died so young, and that she would not have suffered from diabetes or HBP, if she has practiced CRON.  There is no proof of that, just a lot of evidence that suggests it.
      Rate this comment: 12345
      Guest (John)
      06/07/2006
      Posts:1
  • Anorexia?
    I wonder what distinguishes people who severely restrict their caloric intake from people who suffer from anorexia nervosa. I suppose that one group is thinking about health while the other is thinking about appearance. I'm all in favor of seeing what the research tells us. But I fear that this could become a fad, especially among young women.
    Rate this comment: 12345
    Guest (Bob)
    06/07/2006
    Posts:1
    • Did you mean
      Did you mean: What's the difference between "severe" CRONies and those what suffer from AN?  A big difference is that the CRONie knows mal-nutrition is a concern, and thus monitors his/her health, and will adjust their diet accordingly.  AN generally do not do any of these things.  It is a common fear that CRON will lead to AN.  So far there is no evidence of that ever occuring. 
      Rate this comment: 12345
      Guest (John)
      06/07/2006
      Posts:1
  • Mental Capacity
    I have seen multiple reports and several studies about extending lifespan both in humans and other animals, but never any results of caloric restriction on mental abilities of these subjects.  Humans under caloric restriction report feeling cold constantly and often somewhat depressed (not suprising - all they have to do is look in the mirror).  Have mice under CR been tested using mazes and other "brain teasers"?  Given the importance of fat in the brain, I would be surprised if CR had no effect on the various mental activities from coordination to learning and memory.
    Rate this comment: 12345
    Guest (George)
    06/07/2006
    Posts:1
    • Yes
      Yes, mice have been tested. It has nothing to do with fats.  Try neurotransmitters.  We can say that it doesn't have to do with fats because if it has to do with fats, then it ain't caloric restriction.  Rather it would refer to caloric restriction PLUS fat restriction.  The ON part of CRON requires all essential nutrients -including fats are included.  If there ain't enough fat for the brain to work, you ain't eating enough fat.  Of coarse if you are fat, it is OK to believe you should eat more to make sure your brain works.
      Rate this comment: 12345
      Guest (John)
      06/07/2006
      Posts:1
      • Testing CR
        John - could you point us to some studies you refer to on the mental effects...I'm quite interested due to the new reports on Grehlin that indicate increased mental accuity during fasting...Thanks
        Rate this comment: 12345
        Guest (George)
        06/08/2006
        Posts:1
        • Yes
          Rate this comment: 12345
          Guest (John)
          06/08/2006
          Posts:1
    • Mental Effects
      I've been living on ~1600-1800 calories daily average intake.  I'm a genius.  I also suffer from dysthymia, so maybe I'd be more of a genius if I ate "normally" :-)
      Rate this comment: 12345
      Guest (Jonathan Schattke)
      06/07/2006
      Posts:1
  • target calorie intake
    AFAIK, a calorie is actually a measurement of the amount of energy in food. So basically, a restricted calorie diet is like giving your body a smaller battery. If you give your body too small of a battery, you won't be able to function to its full capacity. Give your body too large a battery, and it tries to store the extra energy for use later on, which, in excess, can negatively impact your health.

    Instead of simply reducing calories, I think it's more important for someone to find their target calorie intake.
    Rate this comment: 12345
    Guest (brunascle)
    06/07/2006
    Posts:1
    • And there's the rub!
      How does someone find their target calorie intake?  That's the $64,000 question.  CRONies are doing the best to find what target works best for them
      Rate this comment: 12345
      Guest (John)
      06/07/2006
      Posts:1
      • Re: And there's the rub!
        Exactly, it's very hard. The best someone could do is guess and check.

        I think the main conclusion of the study is that a calorie-focused diet is very healthy, which i totally agree with. Most of us (Americans) probably have a target intake that's lower than our normal diet. But a "calorie-restricted" rather than "calorie-focused" label might give the false impression that the less you eat, the healthier you are.
        Rate this comment: 12345
        Guest (brunascle)
        06/07/2006
        Posts:1
  • CRON And Gastric Pacemaker
    I wonder if combining a gastric pacemaker with CRON would make it easier to tolerate?
    Rate this comment: 12345
    Guest (Richard)
    06/08/2006
    Posts:1
  • A healthier, not longer, life
    All this talk of longevity tends to obscure one of the most important factors for most CRONies: a healthier life.  We seek to die of old age, not disease.
    Rate this comment: 12345
    Guest (Derek Edwards)
    06/11/2006
    Posts:1
  • None of the above
    All you genius's have forgotten one key to perfection in all things Carnal and Spiritual - Balance ! Be able to say that I am in balance.
    I do not tip anyway but stay in the middle.
    Rate this comment: 12345
    Guest (Marco)
    06/14/2006
    Posts:1
  • Another perspective
    I'm guessing that a lot of respondents are 20- and 30-somethings.  I'm 58, and I've been abstinent from recreational drugs, alcohol, and red meat for over 20 years.  Nevertheless, I have been diagnosed with Progressive Supranuclear Palsy, a condition which will likely end my life within the next decade.  Because free radicals are implicated in this poorly understood disease, and since they are a byproduct of food metabolism, I'm looking into CRON as a way of managing my disease and lengthening my life.  I don't want to live to a hundred but it would be nice to see 80 without a feeding tube.  I'd also like to accompany my partner, 11 years my junior, a bit further along on his journey.  I'm not trying to cheat the Grim Reaper, just deliver a feint or two before I give up the fight.

    Stay healthy all of you, love life and one another.
    Rate this comment: 12345

    boston02129
    05/11/2007
    Posts:1
    Avg Rating:
    3/5
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