Fasting Study

[Guest guest]

Fasting Every Other Day Cuts Weight, Ups Crankiness

By Amy Norton

NEW YORK (Reuters Health) - Shunning food every other day may be a feasible way

to slash calories -- if you and those around you don't mind the crankiness that

comes with it, according to researchers.

Their study of 16 nonobese men and women looked at the effects of alternate-day

fasting, an eating plan that interspersed fasting days with " feasting " days that

allowed participants to eat as much as they wanted.

The researchers were interested in whether food deprivation every second day

would be easier on people than counting calories on a daily basis, lead author

Dr. Ravussin told Reuters Health.

They found that the diet plan was indeed " feasible, " at least for the duration

of the 3-week study. Overall, the men and women lost an average of 5 pounds,

while shedding some body fat.

On the other hand, Ravussin said, " most people were not happy " -- a major

problem being the crankiness that erupted on the fasting days and did not abate

over the 3 weeks.

Ravussin and his colleagues at the Pennington Biomedical Research Center in

Baton Rouge, Louisiana, report the findings in the American Journal of Clinical

Nutrition (news - web sites).

Uncovering the most tolerable ways for people to cut calories is not just a

matter of trimming waistlines. A number of studies, Ravussin explained, have now

shown that calorie restriction can extend the lives of everything from yeast and

worms to rodents and, possibly, monkeys.

There are a number of theories on why limiting food might make for a longer,

healthier life. One idea, Ravussin noted, is that slowing the rate of metabolism

reduces the generation of oxygen free radicals, potentially cell-damaging

molecules that are a normal byproduct of the metabolic process.

No one knows if calorie counting can extend human life as it does for some

animals. Ravussin and his colleagues are currently conducting a trial, sponsored

by the National Institutes of Health (news - web sites), which is examining how

long-term dietary restriction affects people's health and longevity.

Studying dietary restriction in people is, of course, far more complicated than

studying it in lab rats. The ongoing trial is investigating how calorie cutting

affects " biomarkers of longevity " in people, such as levels of blood sugar and

insulin, a hormone key in regulating blood sugar.

The trial is testing several methods of dietary restriction -- from pure calorie

cutting to burning extra calories through exercise -- to see which are most

viable.

In the current study, Ravussin's team evaluated the effects of alternate-day

fasting, an approach not included in that trial. They wanted to see if the

eating plan was feasible and whether it influenced biomarkers of longevity, as

well as participants' weight and metabolism.

As mentioned, every other day for 3 weeks the men and women subsisted on

calorie-free beverages and sugarless gum. On the days in between, they ate

whatever they wanted.

According to Ravussin, participants were not able to " make up " for what they

didn't eat on fasting days, and consequently, they generally lost a few pounds

and some fat mass. In addition, their insulin levels declined by an average of

about 57 percent.

However, the researchers also found that many participants said they were

irritable on food-free days, and they did not appear to get used to having an

empty stomach every other day.

Calorie restriction, Ravussin noted, is the only behavior that has so far been

shown to prolong life. " There is a ton of data suggesting that this is the only

way to the 'fountain of youth', if you want, " he said. If the current findings

are any indication, the researcher added, alternate-day fasting may not be the

easiest path to that fountain.

SOURCE: American Journal of Clinical Nutrition, January 2005.

[Guest guest]

Hi All,

It seems that the below indicates that

eating every other day ad lib reduces the

calories that we eat and has all the ear-

marks of CR.

For Figure 2, ß-hydroxybutyrate was approximately 10-fold higher.

Insulin was 3-fold lower and free fatty acids were approximately

4-fold lower.

Nutritional status, dietary intake, and body composition:

Leonie K Heilbronn, R , Corby K , D Anton,

and Ravussin

Alternate-day fasting in nonobese subjects: effects on body weight,

body composition, and energy metabolism

Am J Clin Nutr 2005 81: 69-73.

Background: Prolonged dietary restriction increases the life span

in rodents. Some evidence suggests that alternate-day fasting may

also prolong the life span.

Objective: Our goal was to determine whether alternate-day fasting

is a feasible method of dietary restriction in nonobese humans and

whether it improves known biomarkers of longevity.

Design: Nonobese subjects (8 men and 8 women) fasted every other

day for 22 d. Body weight, body composition, resting metabolic rate

(RMR), respiratory quotient (RQ), temperature, fasting serum glucose,

insulin, free fatty acids, and ghrelin were assessed at baseline and

after 21 d (12-h fast) and 22 d (36-h fast) of alternate-day fasting.

Visual analogue scales were used to assess hunger weekly.

Results: Subjects lost 2.5 ± 0.5% of their initial body weight (P

< 0.001) and 4 ± 1% of their initial fat mass (P < 0.001). Hunger

increased on the first day of fasting and remained elevated (P <

0.001). RMR and RQ did not change significantly from baseline to day

21, but RQ decreased on day 22 (P < 0.001), which resulted in an

average daily increase in fat oxidation of 15 g. Glucose and ghrelin

did not change significantly from baseline with alternate-day

fasting, whereas fasting insulin decreased 57 ± 4% (P < 0.001).

Conclusions: Alternate-day fasting was feasible in nonobese

subjects, and fat oxidation increased. However, hunger on fasting

days did not decrease, perhaps indicating the unlikelihood of

continuing this diet for extended periods of time. Adding one small

meal on a fasting day may make this approach to dietary restriction

more acceptable.

Key Words: Resting metabolic rate • fat oxidation • insulin •

glucose • biomarkers of longevity

INTRODUCTION

Prolonged dietary restriction (DR) is the only proven method of

increasing the life span in rodents, flies, yeast, and worms (1). The

mechanism or mechanisms by which DR increases life span are unclear,

but the effects of DR include reduced metabolic rate, reduced

oxidative damage, altered neuroendocrine signaling, and improved

insulin sensitivity (2). The effect of prolonged DR on the life span

in nonhuman primates is currently being investigated (3-5). Although

conclusive results are years away, many improvements in biomarkers of

longevity, including reduced core temperature, resting metabolic rate

(RMR), dehydroepiandrosterone sulfate, glucose, and insulin, have

already been observed. Prolonged DR also alters the expression of

many genes from skeletal muscle, brain, and liver, including genes

encoding heat shock proteins and uncoupling proteins and genes

involved in oxidative damage (6-8). Recent microarray results in

mouse liver indicate that there is significant overlap of

genes that are up-regulated by short-term starvation and by

prolonged DR (9).

Alternate-day fasting may therefore be an alternative to prolonged

DR as a method of increasing maximal life span. Goodrick et al (10)

found that alternate-day fasting increased median and maximal life

span in C57Bl/6 mice when it was introduced at 1.5 and 6 mo of age

and increased maximal, but not median, life span in A/J mice.

Recently, Anson et al (11) observed that mice fed every other day

consumed the same total energy as did ad libitum fed animals and had

similar body weights but had reduced glucose and insulin

concentrations and increased resistance to endotoxic stress (11).

A pilot study testing the feasibility and effects of long-term DR

on biomarkers of longevity in nonobese humans is currently under

investigation. This randomized clinical trial named CALERIE

(sponsored by the National Institute of Aging) is testing numerous

behavioral strategies and diets (ranging from liquid energy to 20–30%

DR to increased energy expenditure by physical activity) to determine

which of these will prove the most viable in today's " obesogenic "

environment. However, the feasibility and efficacy of alternate-day

fasting is not being investigated. Given the difficulty that

individuals have in estimating energy intake (12-14), alternate-day

fasting may prove to be a less complicated method than prolonged DR

in humans. Indeed, one study investigated the effects of alternate-

day DR for 3 y (15). In that study, the subjects were allowed 1 L of

milk and 2–3 pieces of fruit on their energy-restricted day and 9600

kJ/d on the other day. The control group was fed 9600 kJ/d

every day. The subjects randomly assigned to alternate-day DR spent

less time in the infirmary and had a lower death rate than in the

control group (6 versus 13; NS) (16). The present study was

undertaken to determine the feasibility of alternate-day fasting in

nonobese subjects. In addition, the effects of alternate-day fasting

on body weight, RMR, fat oxidation, and biomarkers of longevity were

investigated.

Subjects

Healthy, nonobese [body mass index (in kg/m2) range: 20.0–30.0] men

(n = 8) and women (n = 8) aged between 23 and 53 y were recruited

(Table 1). The subjects had different levels of physical activity: 7

were sedentary, 3 were moderately active (exercised 1–2 times/wk),

and 6 were quite active (exercised 4–5 times/wk). Competitive

athletes and subjects with type 2 diabetes were excluded. ....

Study design

The subjects attended the clinical research center on 2 consecutive

days at baseline (days –2 and –1) and on 2 consecutive days after 3

wk of alternate-day fasting following a " feast " day (day 21) and

following a " fast " day (day 22). The subjects had therefore fasted 12

h (overnight) on days –2, –1, and 21 and 36 h on day 22. The subjects

were instructed to avoid exercise, alcohol, and coffee for 24 h

before each visit. ... At baseline and on days 1, 7, 15, and 21

(fasting days), the subjects completed visual analogue scales (VASs)

at 1000, 1200, 1400, and 1600 to assess their feelings of hunger,

fullness, desire to eat, satisfaction, and prospective food

consumption (17). ... the subjects also completed the Eating

Inventory questionnaire, which assessed dietary restraint (the intent

and ability to restrict caloric intake), disinhibition (the tendency

to overeat), and hunger (18). The subjects also completed a nine-item

self-report questionnaire, which was developed for this study,

to assess eating attitudes and behaviors with the use of an 8-point

scale. This questionnaire (Eating Behaviors Questionnaire) assessed

whether the subjects consider themselves " dieters " who watch what

they eat or " big eaters " who tend to eat 1 or 2 large meals per day.

After baseline testing was completed, the subjects fasted from

midnight to the subsequent midnight on alternating days for 22 d. On

each fasting day, the subjects were allowed to consume energy-free

beverages, tea, coffee, and sugar-free gum and were instructed to

keep their water intake high. On each feasting day, the subjects were

instructed to eat whatever they wished and were informed that double

their usual food intake would be required to maintain their usual

body weight. The subjects were provided with calibrated digital

scales (Tanita, Arlington Heights, IL) to record their morning

fasting body weight, urinary sticks to test for the presence of

ketones, and a diet diary to record anything that was consumed on the

fasting day. On day 20, the subjects were required to fast from 1900

so that a 12-h overnight fast would be completed before testing began

the following morning at 0700. They did not break this fast until

after their clinic visit on day 22. ...

RESULTS

The subjects' characteristics by sex are given in Table 1. On the

basis of their self-recorded diet diaries and weight logs (Figure 1),

the subjects complied with the protocol. Urinary ketones were not

useful as a measure of compliance because they were not consistently

detected in all subjects (data not shown). On the basis of daily

regressed body weights, the subjects lost 2.5 ± 0.5% of their initial

body weight. This self-reported weight loss was confirmed by weights

measured in the clinic at baseline and on days 21 and 22 (P < 0.001).

Significant reductions were observed in fat mass (P < 0.001) and fat-

free mass (P < 0.05) after the intervention (Figure 1).

On average, the men considered themselves " big eaters, " and the

women reported that they " watched what they ate. " Percentage weight

loss did not differ significantly between the men and the women, but

weight loss correlated negatively with considering oneself a big

eater after adjustment for sex (r = –0.63, P = 0.04). The dietary

restraint and disinhibition scales of the Eating Inventory

questionnaire did not significantly predict weight loss.

VASs were completed for all days by only 8 of 16 subjects. First,

baseline results were compared with the first day of fasting. As

expected, a significant increase was found in feelings of hunger

(from 37 ± 5 to 56 ± 4 mm; P < 0.001), and a significant decrease was

noted in feelings of fullness (from 43 ± 3 to 23 ± 4 mm; P < 0.001).

However, repeated-measures analysis over time (days 1, 7, 15, and 21)

showed no significant changes in the subjects' perception of hunger,

thirst, desire to eat, or feelings of satisfaction, although feelings

of fullness increased slightly over time (P < 0.05).

Temperature (data not shown) and absolute and relative resting

metabolic rate (adjusted for fat-free mass and fat mass) were not

significantly different from baseline (Table 2). Respiratory quotient

(RQ) was also not significantly different from baseline at day 21;

however, RQ was lower on day 22 (P < 0.001; Table 2). More

specifically, fat oxidation increased from 64 g/24 h at baseline to

101 g/24 h, and carbohydrate oxidation decreased from 175 to 81 g/24

h. The change in RQ from baseline to day 21 was related to weight

loss (r = –0.76, P < 0.001).

The women had significantly lower glucose, insulin, free fatty

acid, triacylglycerol, and LDL-cholesterol concentrations and

significantly higher HDL-cholesterol and ghrelin concentrations than

did the men (P < 0.05). Fasting glucose was not significantly changed

from baseline in the men or the women (Figure 2). Fasting insulin was

lower on day 22 in both the men and the women (P < 0.001), and

fasting ß-hydroxybutyrate and free fatty acid concentrations were

higher on day 22 in both the men and the women (Figure 2; P < 0.001).

Fasting ghrelin was not significantly altered from baseline on day 21

(results not shown) or day 22 (from 1019 ± 128 to 1063 ± 158 pg/mL in

the men and from 1403 ± 63 to 1493 ± 139 pg/mL in the women).

Systolic and diastolic blood pressure were not significantly altered

by the intervention (data not shown). HDL was elevated from baseline

in the women only (P < 0.001; data not shown), and triacylglycerol

was significantly reduced from baseline in the men only

(P < 0.05; data not shown).

DISCUSSION

Alternate-day fasting may be an alternative to prolonged DR for

increasing the life span (11). In the present study, we report that

alternate-day fasting is feasible for short time periods in nonobese

subjects. One participant reported feeling lightheaded once, and 4

subjects reported constipation. No subjects withdrew during the

study, but many reported feeling irritable on their fasting days,

perhaps indicating the unlikelihood of continuing this diet for

extended periods of time. The results from the VASs suggest that

feelings of fullness may have increased from the first fasting day

over the course of the study, but other subjective states related to

food intake motivation did not habituate, including hunger. This

result contrasts with the results of studies using liquid-based, very-

low-energy diets where hunger diminishes despite a marked energy

deficit (19). Overall, these results suggest that a prolonged

schedule of fasting and feasting would be marred by aversive

subjective states (eg, hunger and irritability), which would likely

limit the ability of most individuals to sustain this eating pattern.

This is the first study, to our knowledge, to test the effects of

alternate-day fasting on body weight and other metabolic variables in

humans. Body weight was clearly reduced from baseline after 3 wk of

alternate-day fasting, indicating that the subjects were unable to

consume enough food on the feasting days to maintain their weight.

This is opposite the results observed in rodents, where mice fed

every other day maintained their body weight and consumed roughly the

same amount of food in 1 d that ad libitum–fed animals consumed over

2 d (11). We hypothesized that the subjects with a self-reported

ability to overeat or eat large amounts of food would maintain their

body weight, and this hypothesis was supported: considering oneself

a " big eater " was negatively associated with weight loss when sex was

controlled for by partial correlation. Whether alternate-day fasting

would lead to weight loss in obese participants remains unclear. The

negative subjective states associated with the

study cast doubt on the ability of individuals to voluntarily engage

in alternate-day fasting for prolonged periods of time. Altering the

clock time that the subjects are asked to fast (eg, from 1900 to

1900) or adding a small meal (10–20% of caloric needs) to the fasting

day may make alternate-day fasting more acceptable in all populations.

Ghrelin is a peptide secreted in the gut that is reduced on

feeding and has been implicated in the regulation of feeding behavior

and energy balance. Obese subjects have lower fasting ghrelin

concentrations than do lean subjects (20) but have impaired

suppression of plasma ghrelin in response to a meal (21).

Furthermore, ghrelin is increased after weight loss in obese subjects

(22, 23), perhaps driving the common phenomenon of weight regain

after weight loss. In the present study, the women had significantly

higher ghrelin concentrations than did the men. This has been

reported previously (24) but is not consistently observed (25) and

may be related to central adiposity. In contrast with the large

increases in reported hunger, plasma ghrelin was unchanged in both

the men and the women, even after 36 h of fasting. Studies in rodents

have found that 24-h fasts increase plasma ghrelin (26). However,

fasting for 72 h did not change plasma ghrelin in lean men (24). The

results of

these fasting studies in humans call into question the role of

ghrelin in the hunger drive and highlight the need for further

research in this area.

A hallmark of rodent studies of longevity is reduced fasting

glucose and insulin concentrations and increased insulin sensitivity

in dietary-restricted animals (27). Reduced fasting insulin has also

been associated with increased longevity in humans (27). In the

present study, insulin was reduced after a fast day, suggesting

improved insulin sensitivity. However, plasma free fatty acids were

also elevated after fasting; these elevated concentrations may impair

insulin-mediated glucose disposal and the suppression of hepatic

glucose production (28). We also found that alternate-day fasting did

not significantly change fasting glucose or insulin from baseline

after a 12-h fast. This is in contrast with results in mice, in which

glucose and insulin concentrations were lower after 14-h fasts than

in ad libitum fed–mice or mice fed energy-restricted diets. Thus,

humans may need to fast for longer than 12 h for this effect to be

observed. Alternatively, this could be due to the already

low glucose concentrations of our population or that 3 wk of

alternate-day fasting was insufficient to produce this response. The

study design may also have affected these results, because the

subjects anecdotally reported eating even more than usual on day 20

(knowing they were about to enter a longer than usual fast day).

RMR was not significantly changed after 3 wk of alternate-day

fasting. The effects of 36-h fasts on RMR have not been previously

reported. Horton and Hill (29) observed no differences in metabolic

rate (measured for 12 h in a metabolic chamber after a mixed meal)

between overnight or 3-d fasts. We did observe that subjects oxidized

more fat on day 22 as evidenced by a reduction in RQ from 0.85 to

0.79. However, RQ was not altered on day 21. This suggests that there

were no sustained increases in fat oxidation on fed days. Caution

must be exercised when interpreting this result, because the subjects

did not consume standardized diets and RQ is heavily dependent on fat

intake and energy balance. However, it is more likely that we

underestimated fat oxidation, because the subjects were coming out of

positive energy balance and because overall fat oxidation was

increased by an average of 15 g/d. Furthermore, because weight loss

is positively correlated with increased fat oxidation,

the results suggest that the subjects with a greater ability to

oxidize fat lost more weight. Alternatively, it could be argued that

the subjects who had a greater caloric deficit had increased fat

oxidation.

In conclusion, alternate-day fasting is feasible in nonobese

subjects for short time periods, although unlike rodents, the

subjects were unable to maintain their body weight. Furthermore, fat

oxidation was increased and translated into fat mass loss. Hunger on

fasting days did not habituate over the course of the study, which

perhaps indicates the unlikelihood of subjects continuing on this

diet for extended periods of time. Whether alternate-day fasting

would promote weight loss in an obese population is uncertain.

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TABLE 1 Baseline characteristics of the participants by sex1

Men (n = 8) Women (n = 8)

-------------------------------

Age (y) 34 ± 3 30 ± 1

Weight (kg) 80.6 ± 4.4 59.7 ± 1.72

BMI (kg/m2) 25.2 ± 1.1 22.6 ± 0.6

Fat mass (%) 22 ± 2 25 ± 1

Cholesterol (mmol/L) 4.9 ± 0.4 4.7 ± 0.2

HDL (mmol/L) 1.0 ± 0.1 1.8 ± 0.12

Triacylglycerols (mmol/L) 2.5 ± 0.6 1.1 ± 0.12

Systolic blood pressure (mm Hg) 116 ± 2 104 ± 32

Diastolic blood pressure (mm Hg) 75 ± 3 68 ± 2

1 All values are ± SEM.

2 Significantly different from men, P < 0.01 (one-factor ANOVA).

TABLE 2 Resting metabolic rate (RMR), respiratory quotient (RQ),

and fat and carbohydrate oxidation measured at baseline and after a

fed day (day 21) and a fast day (day 22)1

Baseline Day 21 Day 22

--------------------------------------------------

RMR (kJ/d) 6675 ± 283 6292 ± 268 6329 ± 260

RQ 0.85 ± 0.01 0.86 ± 0.02 0.79 ± 0.012

Fat oxidation (g/24 h)3 64 ± 8 54 ± 10 101 ± 92

Carbohydrate oxidation (g/24 h)3 175 ± 17 184 ± 24 81 ± 162

1 All values are ± SEM. Two consecutive days at baseline were

averaged for analysis.

2 Significantly different from baseline, P < 0.001 (one-factor

repeated-measures ANOVA).

3 Calculated by assuming that protein oxidation was 15% of RMR.

Cheers, Al Pater.

--- In , " Jeff Novick " <jnovick@p...>

wrote:

> Fasting Every Other Day Cuts Weight, Ups Crankiness

>

>

> By Amy Norton

>

> NEW YORK (Reuters Health) - Shunning food every other day may be a

feasible way to slash calories -- if you and those around you don't

mind the crankiness that comes with it, according to researchers.

>

> Their study of 16 nonobese men and women looked at the effects of

alternate-day fasting, an eating plan that interspersed fasting days

with " feasting " days that allowed participants to eat as much as they

wanted.

>

> The researchers were interested in whether food deprivation every

second day would be easier on people than counting calories on a

daily basis, lead author Dr. Ravussin told Reuters Health.

>

> They found that the diet plan was indeed " feasible, " at least for

the duration of the 3-week study. Overall, the men and women lost an

average of 5 pounds, while shedding some body fat.

>

> On the other hand, Ravussin said, " most people were not happy " -- a

major problem being the crankiness that erupted on the fasting days

and did not abate over the 3 weeks.

>

> Ravussin and his colleagues at the Pennington Biomedical Research

Center in Baton Rouge, Louisiana, report the findings in the American

Journal of Clinical Nutrition (news - web sites).

>

> Uncovering the most tolerable ways for people to cut calories is

not just a matter of trimming waistlines. A number of studies,

Ravussin explained, have now shown that calorie restriction can

extend the lives of everything from yeast and worms to rodents and,

possibly, monkeys.

>

> There are a number of theories on why limiting food might make for

a longer, healthier life. One idea, Ravussin noted, is that slowing

the rate of metabolism reduces the generation of oxygen free

radicals, potentially cell-damaging molecules that are a normal

byproduct of the metabolic process.

>

> No one knows if calorie counting can extend human life as it does

for some animals. Ravussin and his colleagues are currently

conducting a trial, sponsored by the National Institutes of Health

(news - web sites), which is examining how long-term dietary

restriction affects people's health and longevity.

>

> Studying dietary restriction in people is, of course, far more

complicated than studying it in lab rats. The ongoing trial is

investigating how calorie cutting affects " biomarkers of longevity "

in people, such as levels of blood sugar and insulin, a hormone key

in regulating blood sugar.

>

> The trial is testing several methods of dietary restriction -- from

pure calorie cutting to burning extra calories through exercise -- to

see which are most viable.

>

> In the current study, Ravussin's team evaluated the effects of

alternate-day fasting, an approach not included in that trial. They

wanted to see if the eating plan was feasible and whether it

influenced biomarkers of longevity, as well as participants' weight

and metabolism.

>

> As mentioned, every other day for 3 weeks the men and women

subsisted on calorie-free beverages and sugarless gum. On the days in

between, they ate whatever they wanted.

>

> According to Ravussin, participants were not able to " make up " for

what they didn't eat on fasting days, and consequently, they

generally lost a few pounds and some fat mass. In addition, their

insulin levels declined by an average of about 57 percent.

>

> However, the researchers also found that many participants said

they were irritable on food-free days, and they did not appear to get

used to having an empty stomach every other day.

>

> Calorie restriction, Ravussin noted, is the only behavior that has

so far been shown to prolong life. " There is a ton of data suggesting

that this is the only way to the 'fountain of youth', if you want, "

he said. If the current findings are any indication, the researcher

added, alternate-day fasting may not be the easiest path to that

fountain.

>

> SOURCE: American Journal of Clinical Nutrition, January 2005.

[Guest guest]

Hi Al:

Gosh those women were a lot healthier than the males! Much lower

BMI; much better lipids; and BP of 104/68? All BEFORE the study

started.

It will be interesting to compare these results with those of

Mattson's study due out later in the year looking at people eating

one meal only each day, in the early evening.

Finally, we are beginning to see studies that are looking at meal

frequency. It would be nicer, of course, if they were done on people

who were already calorically restricted.

Since the benefits of restriction are now beyond dispute, if we wish

to determine the way to prolong maximal lifespan the most, logically

the control groups should be restricted individuals, and the

experimental groups some variation in the method of implementation of

restriction, imo.

Rodney.

> > Fasting Every Other Day Cuts Weight, Ups Crankiness

> >

> >

> > By Amy Norton

> >

> > NEW YORK (Reuters Health) - Shunning food every other day may be

a

> feasible way to slash calories -- if you and those around you don't

> mind the crankiness that comes with it, according to researchers.

> >

> > Their study of 16 nonobese men and women looked at the effects of

> alternate-day fasting, an eating plan that interspersed fasting

days

> with " feasting " days that allowed participants to eat as much as

they

> wanted.

> > SOURCE: American Journal of Clinical Nutrition, January 2005.

[Guest guest]

Hi Al:

I doubt that eating every other day will not be a widely successful

method of restriction. My reason is that eating huge meals every

other day will prevent any shrinkage in stomach capacity. Whereas

eating small amounts daily may well result in a smaller stomach size.

I have no evidence of this beyond my own experience. Shrinkage in

stomach capacity is simply the best explanation I can come up with to

explain why I find restriction a lot easier after a couple of months

of efforts. As previously explained.

Rodney.

> > > Fasting Every Other Day Cuts Weight, Ups Crankiness

> > >

> > >

> > > By Amy Norton

> > >

> > > NEW YORK (Reuters Health) - Shunning food every other day may

be

> a

> > feasible way to slash calories -- if you and those around you

don't

> > mind the crankiness that comes with it, according to researchers.

> > >

> > > Their study of 16 nonobese men and women looked at the effects

of

> > alternate-day fasting, an eating plan that interspersed fasting

> days

> > with " feasting " days that allowed participants to eat as much as

> they

> > wanted.

>

> > > SOURCE: American Journal of Clinical Nutrition, January 2005.

[Guest guest]

Corrected .................... (a 'not' deleted)

> Hi Al:

>

> I doubt that eating every other day will be a widely successful

> method of restriction. My reason is that eating huge meals every

> other day will prevent any shrinkage in stomach capacity. Whereas

> eating small amounts daily may well result in a smaller stomach

size.

>

> I have no evidence of this beyond my own experience. Shrinkage in

> stomach capacity is simply the best explanation I can come up with

to

> explain why I find restriction a lot easier after a couple of

months

> of efforts. As previously explained.

>

> Rodney.

[Guest guest]

Dude, stomachs don't really shrink....

On Wed, 02 Feb 2005 20:56:36 -0000, Rodney <perspect1111@...> wrote:

>

>

> Corrected .................... (a 'not' deleted)

>

> > Hi Al:

> >

> > I doubt that eating every other day will be a widely successful

> > method of restriction. My reason is that eating huge meals every

> > other day will prevent any shrinkage in stomach capacity. Whereas

> > eating small amounts daily may well result in a smaller stomach

> size.

> >

> > I have no evidence of this beyond my own experience. Shrinkage in

> > stomach capacity is simply the best explanation I can come up with

> to

> > explain why I find restriction a lot easier after a couple of

> months

> > of efforts. As previously explained.

> >

> > Rodney.

>

>

>

>

[Guest guest]

Hi :

Well you ought to know. But I am really surprised to hear that. So

many other parts of the body adapt to accomodate the workload put on

them - muscles, brain (function, probably not size), lungs, heart,

skeleton even, why would the stomach be different?

Endurance athletes especially experience an upward adjustment as a

result of training - muscles, lungs, heart. Body builders are

probably the best example of the way muscle adapts to workload. And

as soon as they stop the workload the extra muscle disappears pretty

quickly. Many sources I have seen claim exercise prompts the

skeleton to maintain bone mass, usually this is noted as a way to

prevent bone loss in osteoporosis. Obese people, it is said, never

get osteoporosis because of the large loads the bones have to carry,

and accordingly adapt to. I have even seen bone grow on the end of a

metal orthopaedic rod because it somehow figured it needed to be

there - more than an inch from the nearest other bone mass! Amazing

adaptation, to me.

In terms of downward adjustment I have very recently been told that

the muscles in my right arm, not being used the next few weeks, will

atrophy to the extent they will need months of physiotherapy to get

them back into half decent shape. Astronauts have similar atrophy

problems with both muscle and bone, because of reduced demands on

them in weightlessness.

Is the stomach different in not adapting to shifts in demand? I am

thinking of the people who eat such huge quantities daily that they

are able to maintain, and even increase, their weight above 1000

pounds in a few cases. How could a regular-sized stomach handle such

volumes of food? Is the stomach the only part of our LBM that does

not get trimmed down in size as people who are transitioning to CRON

lose LBM as well as fat?

If you are sure about this then there must be some other reason why I

have noticed many times over the years that my appetite diminishes

appreciably only after a couple of months trying to restrict but

having difficulty because of hunger.

Interesting issue, either way.

Rodney.

> Dude, stomachs don't really shrink....

>

>

> On Wed, 02 Feb 2005 20:56:36 -0000, Rodney <perspect1111@y...>

wrote:

> >

> >

> > Corrected .................... (a 'not' deleted)

> >

> > > Hi Al:

> > >

> > > I doubt that eating every other day will be a widely successful

> > > method of restriction. My reason is that eating huge meals

every

> > > other day will prevent any shrinkage in stomach capacity.

Whereas

> > > eating small amounts daily may well result in a smaller stomach

> > size.

> > >

> > > I have no evidence of this beyond my own experience. Shrinkage

in

> > > stomach capacity is simply the best explanation I can come up

with

> > to

> > > explain why I find restriction a lot easier after a couple of

> > months

> > > of efforts. As previously explained.

> > >

> > > Rodney.

> >

> >

> >

> >

[Guest guest]

Just did the calculation for calories expended by a male, aged 45,

weighing 1000 pounds, spending 10 hours resting, 10 hours 'very

light' activity and 4 hours 'light' activity.

In very round numbers we are talking about 10,000 calories a day.

Hmmmmm.

Rodney.

> > >

> > >

> > > Corrected .................... (a 'not' deleted)

> > >

> > > > Hi Al:

> > > >

> > > > I doubt that eating every other day will be a widely

successful

> > > > method of restriction. My reason is that eating huge meals

> every

> > > > other day will prevent any shrinkage in stomach capacity.

> Whereas

> > > > eating small amounts daily may well result in a smaller

stomach

> > > size.

> > > >

> > > > I have no evidence of this beyond my own experience.

Shrinkage

> in

> > > > stomach capacity is simply the best explanation I can come up

> with

> > > to

> > > > explain why I find restriction a lot easier after a couple of

> > > months

> > > > of efforts. As previously explained.

> > > >

> > > > Rodney.

> > >

> > >

> > >

> > >

[Guest guest]

Well, your stomach size and length of intestines are pretty static,

regardless of " exercise " or caloric or volumetric intake:

Nutr Rev. 1994 Jan;52(1):1-10. Related Articles, Links

The role of the gut in regulating food intake in man.

Read N, French S, Cunningham K.

Center for Human Nutrition, Northern General Hospital, Sheffield, UK.

In addition to various psychosocial and metabolic factors, food

intake is also influenced by gastrointestinal mechanisms that trigger

both the initiation and termination of eating behaviors. Although

gastric distension is one of the most obvious signs of " fullness " and

clearly plays a role in controlling food intake, its effects are only

temporary and are distinct from the feelings of satiety generally

associated with a meal. Such postprandial sensations appear to be

related to the activation of intestinal chemoreceptors. Other evidence

indicates that the release of cholecystokinin and perhaps other

transmitters as well may contribute to satiety. Although the stomach

probably does not expand or shrink in response to different levels of

food intake, nutrient receptors in the small intestine probably do

adapt to changes in food intake. Intestinal adaptation also occurs in

response to thyroid hormone, insulin, and cortisol as well as to

obesity, pregnancy, and illness, which all may have an important

bearing on changes in eating behavior in these situations.

Publication Types:

* Review

* Review, Tutorial

PMID: 8139794 [PubMed - indexed for MEDLINE]

On Thu, 03 Feb 2005 00:58:31 -0000, Rodney <perspect1111@...> wrote:

>

>

> Hi :

>

> Well you ought to know. But I am really surprised to hear that. So

> many other parts of the body adapt to accomodate the workload put on

> them - muscles, brain (function, probably not size), lungs, heart,

> skeleton even, why would the stomach be different?

>

> Endurance athletes especially experience an upward adjustment as a

> result of training - muscles, lungs, heart. Body builders are

> probably the best example of the way muscle adapts to workload. And

> as soon as they stop the workload the extra muscle disappears pretty

> quickly. Many sources I have seen claim exercise prompts the

> skeleton to maintain bone mass, usually this is noted as a way to

> prevent bone loss in osteoporosis. Obese people, it is said, never

> get osteoporosis because of the large loads the bones have to carry,

> and accordingly adapt to. I have even seen bone grow on the end of a

> metal orthopaedic rod because it somehow figured it needed to be

> there - more than an inch from the nearest other bone mass! Amazing

> adaptation, to me.

>

> In terms of downward adjustment I have very recently been told that

> the muscles in my right arm, not being used the next few weeks, will

> atrophy to the extent they will need months of physiotherapy to get

> them back into half decent shape. Astronauts have similar atrophy

> problems with both muscle and bone, because of reduced demands on

> them in weightlessness.

>

> Is the stomach different in not adapting to shifts in demand? I am

> thinking of the people who eat such huge quantities daily that they

> are able to maintain, and even increase, their weight above 1000

> pounds in a few cases. How could a regular-sized stomach handle such

> volumes of food? Is the stomach the only part of our LBM that does

> not get trimmed down in size as people who are transitioning to CRON

> lose LBM as well as fat?

>

> If you are sure about this then there must be some other reason why I

> have noticed many times over the years that my appetite diminishes

> appreciably only after a couple of months trying to restrict but

> having difficulty because of hunger.

>

> Interesting issue, either way.

>

> Rodney.

>

>

> > >

> > >

> > > Corrected .................... (a 'not' deleted)

> > >

> > > > Hi Al:

> > > >

> > > > I doubt that eating every other day will be a widely successful

> > > > method of restriction. My reason is that eating huge meals

> every

> > > > other day will prevent any shrinkage in stomach capacity.

> Whereas

> > > > eating small amounts daily may well result in a smaller stomach

> > > size.

> > > >

> > > > I have no evidence of this beyond my own experience. Shrinkage

> in

> > > > stomach capacity is simply the best explanation I can come up

> with

> > > to

> > > > explain why I find restriction a lot easier after a couple of

> > > months

> > > > of efforts. As previously explained.

> > > >

> > > > Rodney.

> > >

> > >

> > >

> > >