Re: Alternate day fasting perils

[Guest guest]

Ref Nr 1 is also fun, particularly for history buffs. It's one of

the first, if not the first of McCay's journal articles--the 1930s era

research that is widely credited for making the initial observation that

energy restriction is linked to increased longevity in rodents.

Anyway, as Anson points out, the strain of mouse used in the PNAS article

was chosen on purpose so that weight loss due to calorie restriction could

be parsed away from the timing of feeding, i.e. meal frequency. C57BL/6

are known for their ability to eat (at least) two days rations in one day.

Bottom line: the alternate day fasted animals lost almost no weight but

still benefited from the regimen when challenged with kainic acid, a treatment

which causes neuronal lesions in the same region of the brain that is involved

in human neurodegenerative disease. Thus, there appears to be something

very powerful, at least in terms of neuronal protection, about the timing

and frequency of feeding in addition to overall energy restriction.

At least in this strain of mouse.

For those of us (humans) who are attempting to mimic this approach,

a more immediate concern with alternate day fasting is what appears to

be a gender specific increase in insulin resistance. In a recent

article, (Heilbronn et al., 2005. Obesity Research. 13: 574- 81) Ravussin's

group reported that in addition to increasing the expression of SIRT1

(a good thing), alternate day fasting tended to impair glucose clearance

in women subjects but not men. However, it should be kept in

mind that the subject number for this study was small (16 total; 8 men

and 8 women) and the duration of the study was relatively short (3 weeks).

It is unclear whether or not men would also experience glucose clearance

problems if the duration of IF is longer, or, conversely, if a larger cohort

of women would demonstrate a lack of impairment. At this point it

is just something to keep in mind. Another thing to keep in mind

for those of us practicing either regimen of dietary restriction is that

neither CR or IF have been proven to increase longevity in humans.

The trends look promising, but the actual proof is still to be demonstrated.

Some of us will contribute to proving the theory, one way or the other.

Al Pater wrote:

Hi All,

Below is a paper that may be of interest in detail.

See the below, which is pdf-available.

The discussion of references 2, 7 and 9 appeared to be of interest.

References 2 and 7 are full-text available.

It was surprising that, in the below contained:

"This was a slight misinterpretation of a study in which we showed that,

for C57BL/6

mice, fasting on alternate days and gorging when food is available

mimics caloric

restriction, without any net reduction in caloric intake.2 C57BL/6

mice were not

selected by chance. We knew at the outset that the same regimen in

other strains was

often not beneficial and could even in some circumstances be fatal.3"

Anson RM.

Absolute versus relative caloric intake: clues to the mechanism of

calorie/aging-rate interactions.

Ann N Y Acad Sci. 2004 Jun;1019:427-9. Review.

PMID: 15247058

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve & db=pubmed & dopt=Abstract & list_uids=15247058

.... In April 2003, many news services (including CNN, CBS, News,

and others)

reported that fasting may be good for one's health. This was a slight

misinterpretation of a study in which we showed that, for C57BL/6 mice,

fasting on

alternate days and gorging when food is available mimics caloric restriction,

without any net reduction in caloric intake.2 C57BL/6 mice were not

selected by

chance. We knew at the outset that the same regimen in other strains

was often not

beneficial and could even in some circumstances be fatal.3 The study

was important

not because it showed that an alternate-day fast might promote longevity,

but

because it provided a model that can separate a net reduction in caloric

intake from

the protective effects of CR. By comparing mice fed a limited amount

of food daily

(LD) with those subjected to every-other-day (EOD) feeding, one can

discern which

physiological changes are critical for life extension and which are

not. Changes not

shared by both models are, ipso facto, not necessary for the effect.

The initial event that led to that study occurred at a meeting of the

Gerontological

Society of America in the mid-1990s. Ruth Lipman reported the results

of a study

(subsequently published4) in which rats were fed a calorically supplemented

diet

that included corn oil and sweetened condensed milk. To keep the rats

from becoming

morbidly obese, it was necessary to restrict their access to this food.

They were

limited to an intake that was 8% higher than that of control animals

fed the

standard chow. Intriguingly, the speaker noted during the presentation

that they

"acted restricted," eagerly awaiting food and rapidly consuming it

when provided.

If caloric intake could be dissociated from behavior, could it be dissociated

from

aging rate? The thought seemed far-fetched at first, yet a literature

search

revealed several studies that suggested that the connection was relative

rather than

absolute. Indeed, one indication that this might be so is the well-established

finding that LD feeding, when begun early in life, lowers body weight.

As a result,

the actual amount of food consumed per gram body weight is often higher

in

restricted animals than in ad libitum (AL) controls.5,6

Other lines of evidence also exist. In a dramatic test of the effect

of excess

calories on the rate of aging, rats were trained to wade in a room-temperature,

shoulder-high pool for several hours a day. As a result, extra energy

was required

to maintain body temperature. Rats in the experimental group in this

study ate, on

average, 44% more than their dry counterparts. Life span, however,

was not

shortened. (Indeed, the trend was in the opposite direction for both

average and

maximal life span.)7

Another line of evidence is found in the effects of dietary restriction

on ob?/?

mice in comparison with congenic controls. One group reported that

ob?/? mice fed AL

consumed 4.2 g of food per day; AL controls consumed 3.0 g per day.

CR mice of both

genotypes were LD fed at 2.0 g per day. This is equivalent to a 52%

restriction for

the ob?/? mice and to a 33% restriction for the wild-type mice. Despite

a high level

of body fat, the longest-lived mice were in the restricted ob?/? group.

While not

conclusive, the trend supports the thought that it was the relative

restriction

level rather than the absolute intake that determined longevity.8

The most direct (but rather obscure) study addressing this issue was

published in

1987.9 In that report, EOD feeding was found to increase life span

in C57BL/6J mice

by 56%, while LD feeding (50% of AL intake) increased it by only 36%.

In contrast,

body weight was decreased by less than 10% in the youngest mice of

the EOD group,

but by nearly 50% in the LD group. In both groups, these numbers decreased

with age.

The topic of the study was body weight and aging interactions, and

thus the question

of food intake was not addressed.

The value of these studies is that they provide us with models that

may be used to

study the mechanism by which caloric intake modulates the aging rate.

Holloszy and

showed that there is an increase in AL intake in response to

environmental

conditions that require increased energy expenditure to maintain body

temperature,

without an acceleration in aging rate.7 The effect of CR in combination

with this

treatment is potentially informative. on et al. showed that mice

lacking

leptin are extremely responsive to CR.8 Their findings suggest that

ob?/? mice may

even be "restricted" at intake levels that are AL for the ob+/+ mouse.

This model

could be useful in studying many factors that have been proposed to

play a

mechanistic role in the calorie/aging-rate interaction. Perhaps the

greatest promise

is offered by comparisons of EOD feeding and LD feeding, two commonly

used CR

paradigms. Ingram and Reynolds showed that, in one strain of mice,

both paradigms

result in life extension, despite dramatically different effects on

body weight.9 In

a follow-up to that study, it was demonstrated that the different effects

on body

weight were caused by differences in net caloric intake: in the EOD

fed mice, net

intake approached AL levels.2 Each of these systems offers innumerable

opportunities

for contrast and comparison, and promises to allow us to eliminate

variables that

change coincidentally, not causally, with the alterations in aging

rate.

1. McCay, C.M., M.F. Crowell & L.A. Maynard. 1935. The effects of

retarded growth

upon the length of life span and upon the ultimate body size. J. Nutr.

10: 63-79.

2. Anson, R.M. et al. 2003. Intermittent fasting dissociates beneficial

effects of

dietary restriction on glucose metabolism and neuronal resistance to

injury from

calorie intake. Proc. Natl. Acad. Sci. USA 100: 6216-6220.

http://www.pnas.org.qe2a-proxy.mun.ca/cgi/content/abstract/100/10/6216?ijkey=bdd2d007ee3c2057670f444d79779385f8e0237b & keytype2=tf_ipsecsha

3. Goodrick, C.L. et al. 1990. Effects of intermittent feeding upon

body weight and

lifespan in inbred mice: interaction of genotype and age. Mech. Ageing

Dev. 55:

69-87.

4. Lipman, R.D. et al. 1998. Effects of caloric restriction or augmentation

in adult

rats: longevity and lesion biomarkers of aging. Aging (Milano) 10:

463-470.

5. Masoro, E.J., B.P. Yu & H.A. Bertrand. 1982. Action of food restriction

in

delaying the aging process. Proc. Natl. Acad. Sci. USA 79: 4239-4241.[Abstract]

6. Hubert, M.F. et al. 2000. The effects of diet, ad libitum feeding,

and moderate

and severe dietary restriction on body weight, survival, clinical pathology

parameters, and cause of death in control Sprague-Dawley rats. Toxicol.

Sci. 58:

195-207.

7. Holloszy, J.O. & E.K. . 1986. Longevity of cold-exposed

rats: a reevaluation

of the "rate-of-living theory." J. Appl. Physiol. 61: 1656-1660.

http://jap.physiology.org.qe2a-proxy.mun.ca/cgi/content/abstract/61/5/1656?ijkey=e5a0fe8ac6688f1c6393e53a4cda9178848fabc3 & keytype2=tf_ipsecsha

http://jap.physiology.org.qe2a-proxy.mun.ca/cgi/reprint/61/5/1656?ijkey=e5a0fe8ac6688f1c6393e53a4cda9178848fabc3

8. on, D.E., J.R. Archer & C.M. Astle. 1984. Effects of food

restriction on

aging: separation of food intake and adiposity. Proc. Natl. Acad. Sci.

USA 81:

1835-1838.

9. Ingram, D.K. & M.A. Reynolds. 1987. The relationship of body

weight to longevity

within laboratory rodent species. In Evolution of Longevity in Animals,

pp. 247-282.

Plenum. New York.

Al Pater, PhD; email: old542000@...

Stay connected, organized, and protected. Take the tour:

http://tour.mail./mailtour.html

[Guest guest]

Hi,

About a year ago I remember reading a similar article about

alternate day fasting. I thought it would be too disruptive for my

lifestyle. However, in an attempt to improve my digestion, as

recommended in a book I read, I reduced my overall eating time from

approximately 6:30 am -10:30 pm to 8:00 am- 4:00. I try to get all

my nutrition in an eight hour period. Well, not eating before going

to bed certainly improved my digestion. But also, when I had a

blood test done in 3/08 my fasting glucose improved and my insulin

was low (first insulin test).

Does anyone know of any research along this way of eating? After

reading Lee Shurie's website, it got me thinking about the way my

eating has evolved.

Connie

--- In , Al Pater <old542000@y...>

wrote:

> Hi All,

>

> Below is a paper that may be of interest in detail.

>

> See the below, which is pdf-available.

>

> The discussion of references 2, 7 and 9 appeared to be of interest.

>

> References 2 and 7 are full-text available.

>

> It was surprising that, in the below contained:

>

> " This was a slight misinterpretation of a study in which we showed

that, for C57BL/6

> mice, fasting on alternate days and gorging when food is available

mimics caloric

> restriction, without any net reduction in caloric intake.2 C57BL/6

mice were not

> selected by chance. We knew at the outset that the same regimen in

other strains was

> often not beneficial and could even in some circumstances be

fatal.3 "

>

> Anson RM.

> Absolute versus relative caloric intake: clues to the mechanism of

> calorie/aging-rate interactions.

> Ann N Y Acad Sci. 2004 Jun;1019:427-9. Review.

> PMID: 15247058

>

> http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?

cmd=Retrieve & db=pubmed & dopt=Abstract & list_uids=15247058

>

> ... In April 2003, many news services (including CNN, CBS,

News, and others)

> reported that fasting may be good for one's health. This was a

slight

> misinterpretation of a study in which we showed that, for C57BL/6

mice, fasting on

> alternate days and gorging when food is available mimics caloric

restriction,

> without any net reduction in caloric intake.2 C57BL/6 mice were

not selected by

> chance. We knew at the outset that the same regimen in other

strains was often not

> beneficial and could even in some circumstances be fatal.3 The

study was important

> not because it showed that an alternate-day fast might promote

longevity, but

> because it provided a model that can separate a net reduction in

caloric intake from

> the protective effects of CR. By comparing mice fed a limited

amount of food daily

> (LD) with those subjected to every-other-day (EOD) feeding, one

can discern which

> physiological changes are critical for life extension and which

are not. Changes not

> shared by both models are, ipso facto, not necessary for the

effect.

>

> The initial event that led to that study occurred at a meeting of

the Gerontological

> Society of America in the mid-1990s. Ruth Lipman reported the

results of a study

> (subsequently published4) in which rats were fed a calorically

supplemented diet

> that included corn oil and sweetened condensed milk. To keep the

rats from becoming

> morbidly obese, it was necessary to restrict their access to this

food. They were

> limited to an intake that was 8% higher than that of control

animals fed the

> standard chow. Intriguingly, the speaker noted during the

presentation that they

> " acted restricted, " eagerly awaiting food and rapidly consuming it

when provided.

>

> If caloric intake could be dissociated from behavior, could it be

dissociated from

> aging rate? The thought seemed far-fetched at first, yet a

literature search

> revealed several studies that suggested that the connection was

relative rather than

> absolute. Indeed, one indication that this might be so is the well-

established

> finding that LD feeding, when begun early in life, lowers body

weight. As a result,

> the actual amount of food consumed per gram body weight is often

higher in

> restricted animals than in ad libitum (AL) controls.5,6

>

> Other lines of evidence also exist. In a dramatic test of the

effect of excess

> calories on the rate of aging, rats were trained to wade in a room-

temperature,

> shoulder-high pool for several hours a day. As a result, extra

energy was required

> to maintain body temperature. Rats in the experimental group in

this study ate, on

> average, 44% more than their dry counterparts. Life span, however,

was not

> shortened. (Indeed, the trend was in the opposite direction for

both average and

> maximal life span.)7

>

> Another line of evidence is found in the effects of dietary

restriction on ob–/–

> mice in comparison with congenic controls. One group reported that

ob–/– mice fed AL

> consumed 4.2 g of food per day; AL controls consumed 3.0 g per

day. CR mice of both

> genotypes were LD fed at 2.0 g per day. This is equivalent to a

52% restriction for

> the ob–/– mice and to a 33% restriction for the wild-type mice.

Despite a high level

> of body fat, the longest-lived mice were in the restricted ob–/–

group. While not

> conclusive, the trend supports the thought that it was the

relative restriction

> level rather than the absolute intake that determined longevity.8

>

> The most direct (but rather obscure) study addressing this issue

was published in

> 1987.9 In that report, EOD feeding was found to increase life span

in C57BL/6J mice

> by 56%, while LD feeding (50% of AL intake) increased it by only

36%. In contrast,

> body weight was decreased by less than 10% in the youngest mice of

the EOD group,

> but by nearly 50% in the LD group. In both groups, these numbers

decreased with age.

> The topic of the study was body weight and aging interactions, and

thus the question

> of food intake was not addressed.

>

> The value of these studies is that they provide us with models

that may be used to

> study the mechanism by which caloric intake modulates the aging

rate. Holloszy and

> showed that there is an increase in AL intake in response to

environmental

> conditions that require increased energy expenditure to maintain

body temperature,

> without an acceleration in aging rate.7 The effect of CR in

combination with this

> treatment is potentially informative. on et al. showed that

mice lacking

> leptin are extremely responsive to CR.8 Their findings suggest

that ob–/– mice may

> even be " restricted " at intake levels that are AL for the ob+/+

mouse. This model

> could be useful in studying many factors that have been proposed

to play a

> mechanistic role in the calorie/aging-rate interaction. Perhaps

the greatest promise

> is offered by comparisons of EOD feeding and LD feeding, two

commonly used CR

> paradigms. Ingram and Reynolds showed that, in one strain of mice,

both paradigms

> result in life extension, despite dramatically different effects

on body weight.9 In

> a follow-up to that study, it was demonstrated that the different

effects on body

> weight were caused by differences in net caloric intake: in the

EOD fed mice, net

> intake approached AL levels.2 Each of these systems offers

innumerable opportunities

> for contrast and comparison, and promises to allow us to eliminate

variables that

> change coincidentally, not causally, with the alterations in aging

rate.

>

> 1. McCay, C.M., M.F. Crowell & L.A. Maynard. 1935. The effects of

retarded growth

> upon the length of life span and upon the ultimate body size. J.

Nutr. 10: 63-79.

>

> 2. Anson, R.M. et al. 2003. Intermittent fasting dissociates

beneficial effects of

> dietary restriction on glucose metabolism and neuronal resistance

to injury from

> calorie intake. Proc. Natl. Acad. Sci. USA 100: 6216-6220.

>

> http://www.pnas.org.qe2a-

proxy.mun.ca/cgi/content/abstract/100/10/6216?

ijkey=bdd2d007ee3c2057670f444d79779385f8e0237b & keytype2=tf_ipsecsha

>

> 3. Goodrick, C.L. et al. 1990. Effects of intermittent feeding

upon body weight and

> lifespan in inbred mice: interaction of genotype and age. Mech.

Ageing Dev. 55:

> 69-87.

>

> 4. Lipman, R.D. et al. 1998. Effects of caloric restriction or

augmentation in adult

> rats: longevity and lesion biomarkers of aging. Aging (Milano) 10:

463-470.

>

> 5. Masoro, E.J., B.P. Yu & H.A. Bertrand. 1982. Action of food

restriction in

> delaying the aging process. Proc. Natl. Acad. Sci. USA 79: 4239-

4241.[Abstract]

>

> 6. Hubert, M.F. et al. 2000. The effects of diet, ad libitum

feeding, and moderate

> and severe dietary restriction on body weight, survival, clinical

pathology

> parameters, and cause of death in control Sprague-Dawley rats.

Toxicol. Sci. 58:

> 195-207.

>

> 7. Holloszy, J.O. & E.K. . 1986. Longevity of cold-exposed

rats: a reevaluation

> of the " rate-of-living theory. " J. Appl. Physiol. 61: 1656-1660.

>

> http://jap.physiology.org.qe2a-

proxy.mun.ca/cgi/content/abstract/61/5/1656?

ijkey=e5a0fe8ac6688f1c6393e53a4cda9178848fabc3 & keytype2=tf_ipsecsha

>

> http://jap.physiology.org.qe2a-proxy.mun.ca/cgi/reprint/61/5/1656?

ijkey=e5a0fe8ac6688f1c6393e53a4cda9178848fabc3

>

> 8. on, D.E., J.R. Archer & C.M. Astle. 1984. Effects of food

restriction on

> aging: separation of food intake and adiposity. Proc. Natl. Acad.

Sci. USA 81:

> 1835-1838.

>

> 9. Ingram, D.K. & M.A. Reynolds. 1987. The relationship of body

weight to longevity

> within laboratory rodent species. In Evolution of Longevity in

Animals, pp. 247-282.

> Plenum. New York.

>

> Al Pater, PhD; email: old542000@y...

>

>

>

>

> Stay connected, organized, and protected. Take the tour:

> http://tour.mail./mailtour.html

[Guest guest]

Hi Connieann:

There is a very important study due out soon (next few months, I

think) that is comparing humans eating three meals a day with those

eating only once per day in the early evening. My impression is that

this will give the first really good evidence about the effects of

short term fasting.

This will be very much worth while watching out for, imo.

Rodney.

> > Hi All,

> >

> > Below is a paper that may be of interest in detail.

> >

> > See the below, which is pdf-available.

> >

> > The discussion of references 2, 7 and 9 appeared to be of

interest.

> >

> > References 2 and 7 are full-text available.

> >

> > It was surprising that, in the below contained:

> >

> > " This was a slight misinterpretation of a study in which we

showed

> that, for C57BL/6

> > mice, fasting on alternate days and gorging when food is

available

> mimics caloric

> > restriction, without any net reduction in caloric intake.2

C57BL/6

> mice were not

> > selected by chance. We knew at the outset that the same regimen

in

> other strains was

> > often not beneficial and could even in some circumstances be

> fatal.3 "

> >

> > Anson RM.

> > Absolute versus relative caloric intake: clues to the mechanism of

> > calorie/aging-rate interactions.

> > Ann N Y Acad Sci. 2004 Jun;1019:427-9. Review.

> > PMID: 15247058

> >

> > http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?

> cmd=Retrieve & db=pubmed & dopt=Abstract & list_uids=15247058

> >

> > ... In April 2003, many news services (including CNN, CBS,

> News, and others)

> > reported that fasting may be good for one's health. This was a

> slight

> > misinterpretation of a study in which we showed that, for C57BL/6

> mice, fasting on

> > alternate days and gorging when food is available mimics caloric

> restriction,

> > without any net reduction in caloric intake.2 C57BL/6 mice were

> not selected by

> > chance. We knew at the outset that the same regimen in other

> strains was often not

> > beneficial and could even in some circumstances be fatal.3 The

> study was important

> > not because it showed that an alternate-day fast might promote

> longevity, but

> > because it provided a model that can separate a net reduction in

> caloric intake from

> > the protective effects of CR. By comparing mice fed a limited

> amount of food daily

> > (LD) with those subjected to every-other-day (EOD) feeding, one

> can discern which

> > physiological changes are critical for life extension and which

> are not. Changes not

> > shared by both models are, ipso facto, not necessary for the

> effect.

> >

> > The initial event that led to that study occurred at a meeting of

> the Gerontological

> > Society of America in the mid-1990s. Ruth Lipman reported the

> results of a study

> > (subsequently published4) in which rats were fed a calorically

> supplemented diet

> > that included corn oil and sweetened condensed milk. To keep the

> rats from becoming

> > morbidly obese, it was necessary to restrict their access to this

> food. They were

> > limited to an intake that was 8% higher than that of control

> animals fed the

> > standard chow. Intriguingly, the speaker noted during the

> presentation that they

> > " acted restricted, " eagerly awaiting food and rapidly consuming

it

> when provided.

> >

> > If caloric intake could be dissociated from behavior, could it be

> dissociated from

> > aging rate? The thought seemed far-fetched at first, yet a

> literature search

> > revealed several studies that suggested that the connection was

> relative rather than

> > absolute. Indeed, one indication that this might be so is the

well-

> established

> > finding that LD feeding, when begun early in life, lowers body

> weight. As a result,

> > the actual amount of food consumed per gram body weight is often

> higher in

> > restricted animals than in ad libitum (AL) controls.5,6

> >

> > Other lines of evidence also exist. In a dramatic test of the

> effect of excess

> > calories on the rate of aging, rats were trained to wade in a

room-

> temperature,

> > shoulder-high pool for several hours a day. As a result, extra

> energy was required

> > to maintain body temperature. Rats in the experimental group in

> this study ate, on

> > average, 44% more than their dry counterparts. Life span,

however,

> was not

> > shortened. (Indeed, the trend was in the opposite direction for

> both average and

> > maximal life span.)7

> >

> > Another line of evidence is found in the effects of dietary

> restriction on ob–/–

> > mice in comparison with congenic controls. One group reported

that

> ob–/– mice fed AL

> > consumed 4.2 g of food per day; AL controls consumed 3.0 g per

> day. CR mice of both

> > genotypes were LD fed at 2.0 g per day. This is equivalent to a

> 52% restriction for

> > the ob–/– mice and to a 33% restriction for the wild-type mice.

> Despite a high level

> > of body fat, the longest-lived mice were in the restricted ob–/–

> group. While not

> > conclusive, the trend supports the thought that it was the

> relative restriction

> > level rather than the absolute intake that determined longevity.8

> >

> > The most direct (but rather obscure) study addressing this issue

> was published in

> > 1987.9 In that report, EOD feeding was found to increase life

span

> in C57BL/6J mice

> > by 56%, while LD feeding (50% of AL intake) increased it by only

> 36%. In contrast,

> > body weight was decreased by less than 10% in the youngest mice

of

> the EOD group,

> > but by nearly 50% in the LD group. In both groups, these numbers

> decreased with age.

> > The topic of the study was body weight and aging interactions,

and

> thus the question

> > of food intake was not addressed.

> >

> > The value of these studies is that they provide us with models

> that may be used to

> > study the mechanism by which caloric intake modulates the aging

> rate. Holloszy and

> > showed that there is an increase in AL intake in response

to

> environmental

> > conditions that require increased energy expenditure to maintain

> body temperature,

> > without an acceleration in aging rate.7 The effect of CR in

> combination with this

> > treatment is potentially informative. on et al. showed that

> mice lacking

> > leptin are extremely responsive to CR.8 Their findings suggest

> that ob–/– mice may

> > even be " restricted " at intake levels that are AL for the ob+/+

> mouse. This model

> > could be useful in studying many factors that have been proposed

> to play a

> > mechanistic role in the calorie/aging-rate interaction. Perhaps

> the greatest promise

> > is offered by comparisons of EOD feeding and LD feeding, two

> commonly used CR

> > paradigms. Ingram and Reynolds showed that, in one strain of

mice,

> both paradigms

> > result in life extension, despite dramatically different effects

> on body weight.9 In

> > a follow-up to that study, it was demonstrated that the different

> effects on body

> > weight were caused by differences in net caloric intake: in the

> EOD fed mice, net

> > intake approached AL levels.2 Each of these systems offers

> innumerable opportunities

> > for contrast and comparison, and promises to allow us to

eliminate

> variables that

> > change coincidentally, not causally, with the alterations in

aging

> rate.

> >

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> > Al Pater, PhD; email: old542000@y...

> >

> >

> >

> >

> > Stay connected, organized, and protected. Take the tour:

> > http://tour.mail./mailtour.html