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Calorie restrictive eating for longer life? The story we didn’t hear in the news

junkfoodscience.blogspot.com

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Re: Calorie restrictive eating for longer life? The story we didn’t hear in the news

#41

Post by Periodic »

ellyagg wrote: post #34
sunburnt wrote: post #10

The article in Science concludes with this: "Weindruch and his collaborators plan to continue monitoring the remaining monkeys, which could stretch the study's length past 3 decades. "If we reach the 40-year-old life span, the study could continue for another 15 years," Weindruch said." The NY Times article says: “Ultimately the results seem pretty inconclusive at this point,” Dr. Austad said. “I don’t know why they…

I don't see how prudent it is. What can I do with that information, given the rest of the results of the study? I don't have anything against diabetes, cancer or heart/brain disease per se. It's not as if, when I die from an infection or pneumonia, I'll congratulate myself that it wasn't cancer! I guess what I'm trying to say is that, if you consider it "prudent to note the reduced rate of diabetes, cancer, and heart…

It's that all-cause mortality factor.

Sure, it may be reducing the causes of some diseases, but if it isn't improving the overall life span of the monkeys or their quality of life it has very limited application.

Perhaps it will turn out that those with a restricted diet who make it through the first 30 years make it through the next 40 as long as they don't fall and break their osteoperotic bones or get exposed to a disease.

As it currently stands, the study is showing no difference. Sitting around for another 25 years on the hope that the trend might change sounds a bit like unfounded faith to me.

Re: Calorie restrictive eating for longer life? The story we didn’t hear in the news

#42

Post by Periodic »

ellyagg wrote: post #36
geuis wrote: post #5

I take issue with much of what was said in this article. Many, if not all of the examples the author refers to are explicit in there statements and not being vague. Additionally, the results of the studies are available for review and carefully explain the reasons why some deaths were not inluded in the results. The author is picking apart chosen pieces of text and apparently has not read the actual study results.

What are you talking about? He linked to the study and priced it out for you, but he didn't read it? The article compared the actual findings of the study with what was reported in the media and press releases. I don't care how careful they were in explaining why they vacated many of the deaths; if you're trying to show that monkeys live longer on calorie restricted diets, you can't do that. At least, you can't if yo…

More importantly, you can't let the media go and publish that you found something when you didn't.

That, particularly, is what makes this junk science. The data isn't necessarily incorrect or contaminated, but we have to be careful not to over-generalize the findings.

There are too many factors not accounted for in this study to apply it to general use in humans. My favorite example is that laboratory colonies are isolated from many pathogens, and thus they exclude disease interaction. In most studies this is desired, but in a whole-life study like this it cannot be ignored if it will be applied to people out in the wild.

This study can only be used to think about this specific effect on aging in isolation and look for mechanisms which we can then test in the general population.

Re: Calorie restrictive eating for longer life? The story we didn’t hear in the news

#43

Post by Periodic »

davi wrote: post #14
geuis wrote: post #5

I take issue with much of what was said in this article. Many, if not all of the examples the author refers to are explicit in there statements and not being vague. Additionally, the results of the studies are available for review and carefully explain the reasons why some deaths were not inluded in the results. The author is picking apart chosen pieces of text and apparently has not read the actual study results.

Agreed. I stopped reading when the author got into a snit because "Control animals were fed 20% more than their average daily intake". It seems clear from context that that was to allow the animals to eat as much as they wanted, the animals were not force-fed 20% more. They're given extra food in case they feel extra hungry that day. It's standard in caloric restriction experiments to feed one group of animals ad lib…

On food availability: many animals, such as mice and dogs, are less able to restrain their own diet and will overeat if allowed to do so. This would lead to the control group overeating, not eating only the number of calories they need, and increasing their chance of obesity-related death. I think a better study might have given the control group the expected number of calories they would require, then significantly restricted the test group.

This study also did not support that calorie restriction increases lifespan, like you do. No study has been able to do that yet. All the studies have been able to do is show that laboratory animals can live longer with a restricted calorie diet. There are many variables controlled for in those studies which are not controlled for in the general human population.

Do you get more exercise than simply sitting in your bedroom all day? If so you do not match the studies. Do you interact with people outside your home or do people ever come into your home? If so you do not match the studies. Were you bred for laboratory study? If not you do not match the studies.

No one has show that calorie restrictive diets have worked in humans yet. Evidence is the best studies, like this one, have not been able to show a statistically significant difference in life span.

Re: Calorie restrictive eating for longer life? The story we didn’t hear in the news

#44

Post by Periodic »

Confusion wrote: post #6
JacobAldridge wrote: post #2

Basically, rhesus monkeys on a restricted calorie diet only lived longer if you remove "non-aging related deaths" . But some of those deaths (eg, dying under anesthesia during a blood test) could have links to their diet, so removing them is just withdrawing non-supporting evidence to prove your (pharma-funded) hypothesis. In other news, riding your bike to work is considered safer than driving a car ... once we remo…

could have links to their diet Replace that with could have been caused by aliens to see how ridiculous that sort of claim is. There is no reason to suppose that dying under anesthesia is related to the diet. Also your analogy doesn't make any sense. Perhaps if they removed bikers that died in traffic accidents while not riding a bike . And then you could argue 'bikers behave differently in traffic, so perhaps biking…

I think his point would be best supported by the note that the study has not found a statistically significant difference in mortality between the restricted and unrestricted diets. It found that aging-related causes of death (cancer and heart disease) were reduced by a factor of three. This implies that the calorie restricted monkeys had higher-than-control rates of mortality due to non-aging effects, such as anesthesia and disease.

Re: Calorie restrictive eating for longer life? The story we didn’t hear in the news

#45

Post by Sikander »

eru wrote: post #20
JulianMorrison wrote: post #16

I've heard a talk recently by a guy who works with scientists who do calorie restriction experiments. What he said is an eye-opener. The animals look healthier but they don't live longer. They don't seem to die of age, but they do just drop dead one day, not always from any obvious cause at all - although they seem particularly susceptible to infections. His hypothesis was that calorie restriction works by forcing th…

Slack and crud?

He meant Slax and Crux! These two linux distros will kill us ALL! :)

Re: Calorie restrictive eating for longer life? The story we didn’t hear in the news

#46

Post by Periodic »

edw519 wrote: post #13

One of the few negative things about the growth of the internet is how much people rely on it for health information. Sometimes I think they'd be better off flipping a coin.

In general I'd support that we have medical professionals to make these decisions for us. I would prefer to have someone I trust, is well educated on the subject, and keeps up with the literature who can point me in the right direction. One result of the specialization in our society and our inability to stay on top of every subject that affects our lives, is that no one can make a truly informed claim on every life decision.

Sadly, many health practitioners are less motivated by science and more motivated by process. They stop educating themselves after they have finished their residency equivalent. Once they are in charge of medical decisions they are bombarded with marketing, which has the goal of selling products, not necessarily with helping anyone.

At this point, I don't know who to trust for medical advice.

Re: Calorie restrictive eating for longer life? The story we didn’t hear in the news

#47

Post by JulianMorrison »

sailormoon wrote: post #38
cdr wrote: post #24

Earlier quoted context omitted.

What a wonderful... anecdote.

Why the downvotes? It's absolutely true. "I heard something" is not a proper argument, and the claim that CR has no effect on lifetime is at odds with everything I've heard on the matter. One of my friends (Chemistry PhD) is crazy about the subject, has read all the studies and he's very excited about the insight CR discoveries may bring. So .. harsh but fair. Anecdotes are worthless. Source please. And cdr should be…

It would be a terrible way to write an academic paper - which I'm not doing, I'm just mentioning the content of a related talk I'd heard. Please avail yourself of the primary sources.

Re: Calorie restrictive eating for longer life? The story we didn’t hear in the news

#48

Post by anamax »

Confusion wrote: post #27
anamax wrote: post #23

Earlier quoted context omitted.

> There is no reason to suppose that dying under anesthesia is related to the diet. If monkeys in one group were more likely to die under anesthesia than monkeys in a different group, I'd suspect that something is going on. (Being unimaginative, I'd exclude the possibility that dying under anesthesia causes a low calorie diet.)

If two monkeys in one group died under anesthesia, that doesn't constitute ground to conclude they were more likely to die: it is simply not statistically significant. Hence you may subtract them from the age related deaths.

> If two monkeys in one group died under anesthesia, that doesn't constitute ground to conclude they were more likely to die

I didn't say that two monkeys constituted statistical significance.

> Hence you may subtract them from the age related deaths.

You can subtract them because they're not statistically significant, but you can't conclude that there isn't something going on, which is what "there's no reason to suppose" means.

Suppose that odds of death due to anesthesia is really low (which it is) but that calorie restriction increased it by 10x (which we don't know either way). 10x a really small number is small enough that this study can't observe the effect because it doesn't kill enough monkeys. And yet, that 10x can easily cause two deaths in one pool while the other has 0.

Re: Calorie restrictive eating for longer life? The story we didn’t hear in the news

#49

Post by fingergunslngr »

This is pure speculative thought, but I feel the crux of the problem may be in the tests to determine the caloric load of foods/drinks - they literally just set it on fire, with the fundamental reason being, this is more or less how our body draws energy from what we consume. I could be wrong, but I feel as though my insides constitute something much more intricate and complicated than a furnace. As I see it, the problem lies in our methods of determining the respective energy potential/composition of a given food - the problem may be with the standard of measure, not a method of dietary restriction.

Re: Calorie restrictive eating for longer life? The story we didn’t hear in the news

#50

Post by jongraehl »

sailormoon wrote: post #40

I do not know what I am talking about when it comes to this topic. Neither, it seems, do most others here. We are intelligent laymen, but laymen all the same. So what do we do in order to intelligently judge this blog post? Well, first, let's consider what we know about the contenders. On one side, a number of respected professional scientists conducting a very expensive multi-decade study and publishing the results…

I was entertained by your fact-finding mission. I only skimmed the original diatribe.

Still, the fact that deaths were removed from the data at all (exactly in favor of the pet hypothesis of the researchers) because they "didn't count" is extremely suspicious, even if it may prove justified (by other confirming studies).

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