“The non-aging-related causes of death included monkeys who died while taking blood samples under anesthesia, from injuries or from infections, such as gastritis and endometriosis. These causes may not be aging-related as defined by the researchers, but they could realistically be adverse effects of prolonged calorie restrictions on the animals’ health, their immune system, ability to handle stress, physical agility, cognition or behavior.”
and would also work well with the musings about variability and duration:
“From an evolutionary standpoint, he explained, mice who subsist on less food for a few years is analogous, in terms of natural selection, to humans who survive 20-year famines. But nature seldom demands that humans endure such conditions.
Similar conclusions were reached by Dr. Aubrey D.N.J. de Grey with the Department of Genetics at the University of Cambridge, UK. Species have widely evolved to be able to adapt to transient periods of starvation. “What has been generally overlooked is that the extent of the evolutionary pressure to maintain adaptability to a given duration of starvation varies with the frequency of that duration,” he said.”
(Our ancestors most certainly did have to survive frequent daily shortfalls. Feast or famine.)
Where do you get that I thought I was wrong about CR? I’d like to lose weight but I had been aware for a while that the state of evidence on caloric restriction doing the purported job of extending lifespan in mammals was bad.
The last thing I remember hearing from you about it was that it looked promising, but that the cognitive side effects made it impractical, so you’d settled on just taking the risk (which would, with that set of beliefs and values, be right in some ways, and wrong in others, and more right than wrong). But, for some reason the search bar doesn’t turn up any relevant conversations for “calorie restriction Eliezer” or “caloric restriction Eliezer”, so I couldn’t actually check my memory. Sorry about that.
I’m not seeing anything at all on that site regarding scientific evidence that CR works, except links to news articles (meh) and uncited assertions that studies have been done that came to that conclusion—the latter of which, in light of the issues raised in the article I linked to, I want to know more about before I try to decide whether they’re useful or not. Overall, both the site and the wiki seem to be much more focused on how to do CR than on making any kind of case that CR is a good idea; I don’t think we’re asking the same question, if you consider that site to give good answers.
Sorry, I thought the meaning of “a good idea” would be clear in context. I meant “likely to increase a user’s chance of having a longer lifespan than they would otherwise”.
If that’s the best resource there is, taking CR at all seriously sounds like privileging the hypothesis to me.
If that’s the best resource there is, taking CR at all seriously sounds like privileging the hypothesis to me.
It may be wrong but I don’t think the flaw is that of privileging the hypothesis. If CR actually does work in, say, rats then thinking it may work in humans is at least a worthwhile hypothesis. The essay you found suggests that the evidence for the hypothesis is looking kinda shaky.
Noteworthy: CR is not a particular interest of mine, and I haven’t researched it.
If there are good, solid studies of CR in rats, why doesn’t that site seem to have, or link to, information about them? If that’s the site for CR, and given that it has a publicly editable (yes, I checked) wiki, I’d expect that someone would have added that information, and it’s not there: I searched for both “study” and “studies” in the wiki; nothing about rat studies—or any other animal studies, except a mention of monkey studies—showed up.
They have a reference to a mouse study on the front page of the site:
Weindruch R, et al. (1986). “The retardation of aging in mice by dietary restriction: longevity, cancer, immunity and lifetime energy intake.” Journal of Nutrition, April, 116(4), pages 641-54.
For the evidence from the rat studies, perhaps start with this review article:
“The evidence that bears on the question of the applicability of CR to humans then, is at present indirect. There is nonetheless a great deal of such indirect evidence, enough that we can say with an extremely high degree of confidence that CR will work in humans.”
It turns out that Eliezer might not have been as wrong as he thought he was about passing on calorie restriction.
Well, there’s still intermittent fasting.
IF would get around
and would also work well with the musings about variability and duration:
(Our ancestors most certainly did have to survive frequent daily shortfalls. Feast or famine.)
Where do you get that I thought I was wrong about CR? I’d like to lose weight but I had been aware for a while that the state of evidence on caloric restriction doing the purported job of extending lifespan in mammals was bad.
...huh.
The last thing I remember hearing from you about it was that it looked promising, but that the cognitive side effects made it impractical, so you’d settled on just taking the risk (which would, with that set of beliefs and values, be right in some ways, and wrong in others, and more right than wrong). But, for some reason the search bar doesn’t turn up any relevant conversations for “calorie restriction Eliezer” or “caloric restriction Eliezer”, so I couldn’t actually check my memory. Sorry about that.
That’s a dopey article. My council is to not get your diet advice from there.
“Dopey”?
Suggest a better one?
http://www.crsociety.org/ is the best web resource relating to dietary energy restriction that I am aware of.
I’m not seeing anything at all on that site regarding scientific evidence that CR works, except links to news articles (meh) and uncited assertions that studies have been done that came to that conclusion—the latter of which, in light of the issues raised in the article I linked to, I want to know more about before I try to decide whether they’re useful or not. Overall, both the site and the wiki seem to be much more focused on how to do CR than on making any kind of case that CR is a good idea; I don’t think we’re asking the same question, if you consider that site to give good answers.
That site is the biggest and most comprehensive resource on the topic available on the internet, AFAIK.
Looking at what you say you are looking for, I don’t think we’re asking the same question either. The diet is not “a good idea”—e.g. see:
http://cr.timtyler.org/disadvantages/
Rather, it is a tool—and whether or not it is for you depends on what your aims in life are.
Sorry, I thought the meaning of “a good idea” would be clear in context. I meant “likely to increase a user’s chance of having a longer lifespan than they would otherwise”.
If that’s the best resource there is, taking CR at all seriously sounds like privileging the hypothesis to me.
It may be wrong but I don’t think the flaw is that of privileging the hypothesis. If CR actually does work in, say, rats then thinking it may work in humans is at least a worthwhile hypothesis. The essay you found suggests that the evidence for the hypothesis is looking kinda shaky.
Noteworthy: CR is not a particular interest of mine, and I haven’t researched it.
If there are good, solid studies of CR in rats, why doesn’t that site seem to have, or link to, information about them? If that’s the site for CR, and given that it has a publicly editable (yes, I checked) wiki, I’d expect that someone would have added that information, and it’s not there: I searched for both “study” and “studies” in the wiki; nothing about rat studies—or any other animal studies, except a mention of monkey studies—showed up.
A google site search does turn up this, though.
Don’t bother with the site’s wiki.
They have a reference to a mouse study on the front page of the site:
Weindruch R, et al. (1986). “The retardation of aging in mice by dietary restriction: longevity, cancer, immunity and lifetime energy intake.” Journal of Nutrition, April, 116(4), pages 641-54.
For the evidence from the rat studies, perhaps start with this review article:
Overview of caloric restriction and ageing.
http://www.crsociety.org/archive/read.php?2,172427,172427
I think most in the field agree on that. e.g.:
“”I’m positive that caloric restriction will work in humans to extend median life span,” Fontana says.”
http://pubs.acs.org/cen/science/87/8731sci2.html
A summary from the site wiki:
“The evidence that bears on the question of the applicability of CR to humans then, is at present indirect. There is nonetheless a great deal of such indirect evidence, enough that we can say with an extremely high degree of confidence that CR will work in humans.”
http://en.wiki.calorierestriction.org/index.php/Will_CR_Work_in_Humans%3F
Off the top of your head do you know what CR has been shown to work on thus far?
One of TT’s links says CR works in “mice, hamsters, dogs, fish, invertebrate animals, and yeast.”