Re: Resting metabolic rate and respiratory quotient in human longevity

[Guest guest]

Hi JW:

I am having trouble figuring out the significance of this. Can you

help me out, please?

First, is RQ the ratio of CO2 breathed out to O2 breathed in? Or is

it the ratio of CO2 produced by tissues to the O2 used by tissues?

In other words is it in effect a measure of lung effectiveness? Or

not?

Second, is a high RQ 'good', or is it 'bad' or does it not matter?

Third, what in your view are the principal things we should learn

from this if we want to survive beyond 100?

Or were you hoping we would be able to answer these same questions

for you? ; ^ )))

Thanks.

Rodney.

--- In , " jwwright " <jwwright@e...>

wrote:

> These articles compare " long-lived " (>100) to elderly (75 to 99) and

adults (<50).

> " In multivariate analysis, both RMR and Rq had FFM, WHR, but not

body mass index as significant and independent determinants. "

> " The major finding of our study is that the long-lived female seems

protected from a metabolic age-related decline compared with aged

females. Despite the fact that in the whole group of subjects an age-

related decline in RMR and Rq was found, the analysis restrained to

long-lived subjects showed in this group RMR and Rq greater than that

found in aged subjects. Such a difference might be explained by the

changes in anthropometrics features because long-lived subjects had

lower BMI, FFM, and WHR than aged subjects. "

> Resting metabolic rate and respiratory quotient in human longevity.

> Rizzo MR - J Clin Endocrinol Metab - 01-JAN-2005; 90(1): 409-13

> 15483081 (PubMed)

> Journal of Clinical Endocrinology and Metabolism

> Abstract:

> Significant changes in body composition, body fat distribution, and

resting metabolic rate (RMR) occur with aging. Interestingly, studies

on human longevity pointed out that long-lived subjects are less

prone to the anthropometrics and metabolic derangement normally

observed in the elderly. Indeed, the relationship between energy

expenditure and longevity has been poorly investigated. Thus, energy

expenditure parameters of 28 long-lived subjects were assessed and

compared with those of 26 adults and 27 younger elderly. All subjects

enrolled were female.In the whole population, RMR was negatively

correlated with age (P < 0.05), waist to hip ratio (WHR) (P < 0.001),

fat mass (P < 0.001), and percent body fat (P < 0.03); respiratory

quotient (Rq) displayed an age-related decrease (P < 0.001) and was

negatively correlated with WHR (P < 0.001) and fat-free mass (FFM) (P

< 0.006). In multivariate analysis, both RMR and Rq had FFM, WHR, but

not body mass index as significant and independent determinants.

Splitting the whole study group into subgroups according to age, long-

lived subjects had oxygen volume, carbon dioxide volume, and Rq

significantly higher than aged subjects but lower than adult

subjects. In addition, long-lived subjects had total volume of

expired air and RMR greater than aged subjects but not different from

ones found in adults. In long-lived subjects, Rq was negatively

correlated with percent body fat (P < 0.02), plasma glucose (P <

0.05), free fatty acid (P < 0.05), and WHR (P < 0.05), whereas RMR

was negatively correlated with WHR (P < 0.05). No significant

associations of RMR and Rq with FFM were found. In conclusion, our

data demonstrate that human longevity seems protected toward an age-

related decline. It is likely that the lack of the anthropometrics

derangement may preserve long-lived subjects from the age-related

decrease in energy metabolism.

>

> " Previous studies on human longevity [3] focused their attention on

anthropometrics [3] and endocrine [14] [15] and metabolic [16] [17]

[18] characteristics of long-lived subjects and pointed out that such

a group of subjects are less prone to the anthropometrics and

metabolic derangement normally observed in the elderly. In

particular, human longevity has been shown to be associated with

lower body fat and waist to hip ratio (WHR) and with preserved

insulin action compared with aged subjects. Due to the impact that

anthropometrics features have on energy expenditure, one would also

expect that human longevity is also associated with different energy

expenditure and respiratory quotient (Rq) than ones reported in the

elderly.

>

> Notwithstanding, the relationship between energy expenditure and

longevity has been poorly investigated. To address such an aim, RMR

and Rq were evaluated in human longevity and compared with those in

adults and aged subjects. "

>

>

>

> 14. Paolisso G, Ammendola S, Del Buono A, Gambardella A, Riondino

M, Tagliamonte MR, Rizzo MR, Carella C, Varricchio M 1997 Serum

levels of insulin like growth factor-1 (IGF-1) and IGF-binding

protein 3 in healthy centenarians: relationship with plasma leptin

and lipid concentration, insulin action and cognitive function. J

Clin Endocrinol Metab 82:2204-2209

>

> " Fat intake was lower in centenarians (48.1 ± 2.1 g/day) than those

in adults (78.9 ± 3.5 g/day; P < 0.001) and aged subjects (63.5 ± 3.9

g/day; P < 0.01). In contrast, daily carbohydrate intake in

centenarians (45 ± 8% equivalent to 46.4 ± 3.4 g/day) was not

different from that in aged subjects (43 ± 4% equivalent to 76.2 ±

3.6 g/day) or adults (47 ± 4% equivalent to 88.6 ± 4.4 g/day) as the

percentage of total energy intake, but was the lowest as an absolute

value ( P < 0.01 for all comparisons). "

>

> TABLE 2 -- Metabolic characteristics of the study groups

> Adults <50 yr (n = 30) P Aged 75-99 yr (n = 30) P Centenians

100 yr (n = 19)

> Triglycerides (mmol/L) 0.9 ± 0.4 <0.05 1.2 ± 0.3 <0.03 1.0 ±

0.5

> FFA (mumol/L) 328 ± 77 <0.05 395 ± 78 <0.01 305 ± 71

> Total cholesterol (mmol/L) 5.8 ± 0.8

> 5.7 ± 0.9

> 5.5 ± 0.8(215) (185-245)

> LDL cholesterol (mmol/L) 3.8 ± 0.7 <0.05 4.6 ± 0.5 <0.01 3.0

± 0.5(115)

> HDL cholesterol (mmol/L) 1.8 ± 0.2 <0.01 0.9 ± 0.3 <0.01 1.8

± 0.3(70)

> WBGD (mumol/kg FFM·min) 34.6 ± 1.1 <0.01 22.4 ± 0.4 <0.01

38.1 ± 1.6

>

>

> THE PLASMA insulin-like growth factor I (IGF-I) concentration has

been shown to decline with advancing age [1] ,[2] , but also to be

influenced by sex steroids [3] , nutritional status [4] , and liver

function [5] . More than 80% of plasma IGF-I circulates bound to IGF-

binding protein-3 (IGFBP-3) and forms a large 150-kDa complex that

cannot leave the circulation [1] ; thus, only the unbound form of IGF-

I is considered to be biologically active [6] .

>

> {BUT: " All subjects were normotensive, were taking no medications,

were not smokers, and had no evidence of metabolic or cardiovascular

disease. ...Subjects with a family history of noninsulin-dependent

diabetes mellitus, obesity [body mass index (BMI), >30], or

hypertension were excluded from the study. No woman was taking

hormone replacement therapy before or during the study. " }

>

>

> 15. tti S, Barbesino G, Caterugli P 1993 Complex alteration of

thyroid function in healthy centenarians. J Clin Endocrinol Metab

77:1130-1134

>

> 16. Paolisso G, Tagliamonte MR, Rizzo MR, Manzella D, Gambardella

A, Varricchio M 1998 Oxidative stress and advancing age: results in

healthy centenarians. JAGS 46:833-838

>

> 17. Paolisso G, Gambardella A, Ammendola S, D'Amore A, Balbi V,

Varricchio M, D'Onofrio F 1996 Glucose tolerance and insulin action

in healthy centenarians. Am J Physiol 270:E890-E896

>

> 18. Paolisso G, Gambardella A, Ammendola S, Tagliamonte MR, Rizzo

MR, Capurso A, Varricchio M 1997 Preserved antilipolytic insulin

action is associated with a less atherogenic plasma lipid profile in

healthy centenarians. J Am Geriatr Soc 45:1504-1509

[Guest guest]

First, I don't know much from these studies, since they "chose" the subjects for certain criteria. How they found >100 yos with no cardiac, hypertension, diabetes, problems, etc? I guess they went looking for a group of healthy centis to find out why they had aged less.

To me it says RMR and Rq were functions of fat free mass, waist/hip ratio but not BMI.

The second article explains that a little more and you need to get the full text of both to understand all the factors.

Whether good or not, the factors of the centis were more like the 50's not like the aged (75-99). So whatever the healthy centi's had at 50, they kept it and a ratio of IGF-1 to IGF-binding protein-3 (IGFBP-3)is considered.

What I was looking for was BMI and "long-lived subjects had lower BMI, FFM, and WHR than aged subjects." as we might expect although not all that low (23-25). But the left out those >30. Maybe they didn't have any centi's >30 so they excluded the them in the other groups.

To me it says RMR and Rq were functions of fat free mass, waist/hip ratio but not BMI.

Also the cholesterol was not all that low (215) for people with reasonable BMI, etc.

The centi's diet was not that clear - 48.1 fat grams, and daily carbohydrate intake in centenarians (45 ± 8% equivalent to 46.4 ± 3.4 g/day)

looks like a higher protein diet.

So the point is the long lived members traveled through the adult 50's and 75-99 groups without losing the thing that keeps them from aging. So how do we keep our IGF-1/IGF-1 BP3 ratio high?

Yes, I was looking for help.

Regards.

----- Original Message -----

From: Rodney

Sent: Thursday, June 23, 2005 4:16 PM

Subject: [ ] Re: Resting metabolic rate and respiratory quotient in human longevity

Hi JW:I am having trouble figuring out the significance of this. Can you help me out, please?First, is RQ the ratio of CO2 breathed out to O2 breathed in? Or is it the ratio of CO2 produced by tissues to the O2 used by tissues? In other words is it in effect a measure of lung effectiveness? Or not?Second, is a high RQ 'good', or is it 'bad' or does it not matter?Third, what in your view are the principal things we should learn from this if we want to survive beyond 100?Or were you hoping we would be able to answer these same questions for you? ; ^ )))Thanks.Rodney.> These articles compare "long-lived"(>100) to elderly (75 to 99) and adults (<50). > "In multivariate analysis, both RMR and Rq had FFM, WHR, but not body mass index as significant and independent determinants."> "The major finding of our study is that the long-lived female seems protected from a metabolic age-related decline compared with aged females. Despite the fact that in the whole group of subjects an age-related decline in RMR and Rq was found, the analysis restrained to long-lived subjects showed in this group RMR and Rq greater than that found in aged subjects. Such a difference might be explained by the changes in anthropometrics features because long-lived subjects had lower BMI, FFM, and WHR than aged subjects."> Resting metabolic rate and respiratory quotient in human longevity.> Rizzo MR - J Clin Endocrinol Metab - 01-JAN-2005; 90(1): 409-13> 15483081 (PubMed)> Journal of Clinical Endocrinology and Metabolism> Abstract:> Significant changes in body composition, body fat distribution, and resting metabolic rate (RMR) occur with aging. Interestingly, studies on human longevity pointed out that long-lived subjects are less prone to the anthropometrics and metabolic derangement normally observed in the elderly. Indeed, the relationship between energy expenditure and longevity has been poorly investigated. Thus, energy expenditure parameters of 28 long-lived subjects were assessed and compared with those of 26 adults and 27 younger elderly. All subjects enrolled were female.In the whole population, RMR was negatively correlated with age (P < 0.05), waist to hip ratio (WHR) (P < 0.001), fat mass (P < 0.001), and percent body fat (P < 0.03); respiratory quotient (Rq) displayed an age-related decrease (P < 0.001) and was negatively correlated with WHR (P < 0.001) and fat-free mass (FFM) (P < 0.006). In multivariate analysis, both RMR and Rq had FFM, WHR, but not body mass index as significant and independent determinants. Splitting the whole study group into subgroups according to age, long-lived subjects had oxygen volume, carbon dioxide volume, and Rq significantly higher than aged subjects but lower than adult subjects. In addition, long-lived subjects had total volume of expired air and RMR greater than aged subjects but not different from ones found in adults. In long-lived subjects, Rq was negatively correlated with percent body fat (P < 0.02), plasma glucose (P < 0.05), free fatty acid (P < 0.05), and WHR (P < 0.05), whereas RMR was negatively correlated with WHR (P < 0.05). No significant associations of RMR and Rq with FFM were found. In conclusion, our data demonstrate that human longevity seems protected toward an age-related decline. It is likely that the lack of the anthropometrics derangement may preserve long-lived subjects from the age-related decrease in energy metabolism.> > "Previous studies on human longevity [3] focused their attention on anthropometrics [3] and endocrine [14] [15] and metabolic [16] [17] [18] characteristics of long-lived subjects and pointed out that such a group of subjects are less prone to the anthropometrics and metabolic derangement normally observed in the elderly. In particular, human longevity has been shown to be associated with lower body fat and waist to hip ratio (WHR) and with preserved insulin action compared with aged subjects. Due to the impact that anthropometrics features have on energy expenditure, one would also expect that human longevity is also associated with different energy expenditure and respiratory quotient (Rq) than ones reported in the elderly.> > Notwithstanding, the relationship between energy expenditure and longevity has been poorly investigated. To address such an aim, RMR and Rq were evaluated in human longevity and compared with those in adults and aged subjects."> > > > 14. Paolisso G, Ammendola S, Del Buono A, Gambardella A, Riondino M, Tagliamonte MR, Rizzo MR, Carella C, Varricchio M 1997 Serum levels of insulin like growth factor-1 (IGF-1) and IGF-binding protein 3 in healthy centenarians: relationship with plasma leptin and lipid concentration, insulin action and cognitive function. J Clin Endocrinol Metab 82:2204-2209 > > "Fat intake was lower in centenarians (48.1 ± 2.1 g/day) than those in adults (78.9 ± 3.5 g/day; P < 0.001) and aged subjects (63.5 ± 3.9 g/day; P < 0.01). In contrast, daily carbohydrate intake in centenarians (45 ± 8% equivalent to 46.4 ± 3.4 g/day) was not different from that in aged subjects (43 ± 4% equivalent to 76.2 ± 3.6 g/day) or adults (47 ± 4% equivalent to 88.6 ± 4.4 g/day) as the percentage of total energy intake, but was the lowest as an absolute value ( P < 0.01 for all comparisons)."> > TABLE 2 -- Metabolic characteristics of the study groups > Adults <50 yr (n = 30) P Aged 75-99 yr (n = 30) P Centenians 100 yr (n = 19) > Triglycerides (mmol/L) 0.9 ± 0.4 <0.05 1.2 ± 0.3 <0.03 1.0 ± 0.5 > FFA (mumol/L) 328 ± 77 <0.05 395 ± 78 <0.01 305 ± 71 > Total cholesterol (mmol/L) 5.8 ± 0.8 > 5.7 ± 0.9 > 5.5 ± 0.8(215) (185-245) > LDL cholesterol (mmol/L) 3.8 ± 0.7 <0.05 4.6 ± 0.5 <0.01 3.0 ± 0.5(115) > HDL cholesterol (mmol/L) 1.8 ± 0.2 <0.01 0.9 ± 0.3 <0.01 1.8 ± 0.3(70) > WBGD (mumol/kg FFM·min) 34.6 ± 1.1 <0.01 22.4 ± 0.4 <0.01 38.1 ± 1.6 > > > THE PLASMA insulin-like growth factor I (IGF-I) concentration has been shown to decline with advancing age [1] ,[2] , but also to be influenced by sex steroids [3] , nutritional status [4] , and liver function [5] . More than 80% of plasma IGF-I circulates bound to IGF-binding protein-3 (IGFBP-3) and forms a large 150-kDa complex that cannot leave the circulation [1] ; thus, only the unbound form of IGF-I is considered to be biologically active [6] . > > {BUT: "All subjects were normotensive, were taking no medications, were not smokers, and had no evidence of metabolic or cardiovascular disease. ...Subjects with a family history of noninsulin-dependent diabetes mellitus, obesity [body mass index (BMI), >30], or hypertension were excluded from the study. No woman was taking hormone replacement therapy before or during the study. "}> > > 15. tti S, Barbesino G, Caterugli P 1993 Complex alteration of thyroid function in healthy centenarians. J Clin Endocrinol Metab 77:1130-1134 > > 16. Paolisso G, Tagliamonte MR, Rizzo MR, Manzella D, Gambardella A, Varricchio M 1998 Oxidative stress and advancing age: results in healthy centenarians. JAGS 46:833-838 > > 17. Paolisso G, Gambardella A, Ammendola S, D'Amore A, Balbi V, Varricchio M, D'Onofrio F 1996 Glucose tolerance and insulin action in healthy centenarians. Am J Physiol 270:E890-E896 > > 18. Paolisso G, Gambardella A, Ammendola S, Tagliamonte MR, Rizzo MR, Capurso A, Varricchio M 1997 Preserved antilipolytic insulin action is associated with a less atherogenic plasma lipid profile in healthy centenarians. J Am Geriatr Soc 45:1504-1509

[Guest guest]

Perhaps diet is key. Higher animal protein, at any rate, results in higher IGF-1.

On 6/23/05, jwwright <jwwright@...> wrote:

First, I don't know much from these studies, since they " chose " the subjects for certain criteria. How they found >100 yos with no cardiac, hypertension, diabetes, problems, etc? I guess they went looking for a group of healthy centis to find out why they had aged less.

To me it says RMR and Rq were functions of fat free mass, waist/hip ratio but not BMI.

The second article explains that a little more and you need to get the full text of both to understand all the factors.

Whether good or not, the factors of the centis were more like the 50's not like the aged (75-99). So whatever the healthy centi's had at 50, they kept it and a ratio of IGF-1 to IGF-binding protein-3 (IGFBP-3)is considered.

What I was looking for was BMI and " long-lived subjects had lower BMI, FFM, and WHR than aged subjects. " as we might expect although not all that low (23-25). But the left out those >30. Maybe they didn't have any centi's >30 so they excluded the them in the other groups.

To me it says RMR and Rq were functions of fat free mass, waist/hip ratio but not BMI.

Also the cholesterol was not all that low (215) for people with reasonable BMI, etc.

The centi's diet was not that clear - 48.1 fat grams, and daily carbohydrate intake in centenarians (45 ± 8% equivalent to 46.4 ± 3.4 g/day)

looks like a higher protein diet.

So the point is the long lived members traveled through the adult 50's and 75-99 groups without losing the thing that keeps them from aging. So how do we keep our IGF-1/IGF-1 BP3 ratio high?

Yes, I was looking for help.

Regards.

----- Original Message -----

From: Rodney

Sent: Thursday, June 23, 2005 4:16 PM

Subject: [ ] Re: Resting metabolic rate and respiratory quotient in human longevity

Hi JW:I am having trouble figuring out the significance of this. Can you help me out, please?First, is RQ the ratio of CO2 breathed out to O2 breathed in? Or is it the ratio of CO2 produced by tissues to the O2 used by tissues? In other words is it in effect a measure of lung effectiveness? Or not?Second, is a high RQ 'good', or is it 'bad' or does it not matter?

Third, what in your view are the principal things we should learn from this if we want to survive beyond 100?Or were you hoping we would be able to answer these same questions for you? ; ^ )))

Thanks.Rodney.> These articles compare " long-lived " (>100) to elderly (75 to 99) and adults (<50). > " In multivariate analysis, both RMR and Rq had FFM, WHR, but not

body mass index as significant and independent determinants. " > " The major finding of our study is that the long-lived female seems protected from a metabolic age-related decline compared with aged

females. Despite the fact that in the whole group of subjects an age-related decline in RMR and Rq was found, the analysis restrained to long-lived subjects showed in this group RMR and Rq greater than that found in aged subjects. Such a difference might be explained by the changes in anthropometrics features because long-lived subjects had lower BMI, FFM, and WHR than aged subjects. " > Resting metabolic rate and respiratory quotient in human longevity.> Rizzo MR - J Clin Endocrinol Metab - 01-JAN-2005; 90(1): 409-13

> 15483081 (PubMed)> Journal of Clinical Endocrinology and Metabolism> Abstract:> Significant changes in body composition, body fat distribution, and resting metabolic rate (RMR) occur with aging. Interestingly, studies on human longevity pointed out that long-lived subjects are less prone to the anthropometrics and metabolic derangement normally observed in the elderly. Indeed, the relationship between energy expenditure and longevity has been poorly investigated. Thus, energy expenditure parameters of 28 long-lived subjects were assessed and compared with those of 26 adults and 27 younger elderly. All subjects enrolled were

female.In the whole population, RMR was negatively correlated with age (P < 0.05), waist to hip ratio (WHR) (P < 0.001), fat mass (P < 0.001), and percent body fat (P < 0.03); respiratory quotient (Rq) displayed an age-related decrease (P < 0.001) and was negatively correlated with WHR (P < 0.001) and fat-free mass (FFM) (P < 0.006). In multivariate analysis, both RMR and Rq had FFM, WHR, but not body mass index as significant and independent determinants. Splitting the whole study group into subgroups according to age, long-lived subjects had oxygen volume, carbon dioxide volume, and Rq significantly higher than aged subjects but lower than adult subjects. In addition, long-lived subjects had total volume of expired air and RMR greater than aged subjects but not different from ones found in adults. In long-lived subjects, Rq was negatively correlated with percent body fat (P < 0.02), plasma glucose (P <

0.05), free fatty acid (P < 0.05), and WHR (P < 0.05), whereas RMR was negatively correlated with WHR (P < 0.05). No significant associations of RMR and Rq with FFM were found. In conclusion, our data demonstrate that human longevity seems protected toward an age-

related decline. It is likely that the lack of the anthropometrics derangement may preserve long-lived subjects from the age-related decrease in energy metabolism.> > " Previous studies on human longevity [3] focused their attention on anthropometrics [3] and endocrine [14] [15] and metabolic [16] [17] [18] characteristics of long-lived subjects and pointed out that such a group of subjects are less prone to the anthropometrics and metabolic derangement normally observed in the elderly. In particular, human longevity has been shown to be associated with lower body fat and waist to hip ratio (WHR) and with preserved insulin action compared with aged subjects. Due to the impact that anthropometrics features have on energy expenditure, one would also expect that human longevity is also associated with different energy expenditure and respiratory quotient (Rq) than ones reported in the elderly.> > Notwithstanding, the relationship between energy expenditure and longevity has been poorly investigated. To address such an aim, RMR and Rq were evaluated in human longevity and compared with those in adults and aged subjects. " > > > > 14. Paolisso G, Ammendola S, Del Buono A, Gambardella A, Riondino M, Tagliamonte MR, Rizzo MR, Carella C, Varricchio M 1997 Serum levels of insulin like growth factor-1 (IGF-1) and IGF-binding protein 3 in healthy centenarians: relationship with plasma leptin and lipid concentration, insulin action and cognitive function. J Clin Endocrinol Metab 82:2204-2209 > > " Fat intake was lower in centenarians (48.1 ± 2.1 g/day) than those in adults (78.9 ± 3.5 g/day; P < 0.001) and aged subjects (63.5 ± 3.9 g/day; P < 0.01). In contrast, daily carbohydrate intake in centenarians (45 ± 8% equivalent to 46.4 ± 3.4 g/day) was not different from that in aged subjects (43 ± 4% equivalent to 76.2 ± 3.6 g/day) or adults (47 ± 4% equivalent to 88.6 ± 4.4 g/day) as the percentage of total energy intake, but was the lowest as an absolute value ( P < 0.01 for all comparisons). " > > TABLE 2 -- Metabolic characteristics of the study groups > Adults <50 yr (n = 30) P Aged 75-99 yr (n = 30) P Centenians 100 yr (n = 19) > Triglycerides (mmol/L) 0.9 ± 0.4 <0.05 1.2 ± 0.3 <0.03 1.0 ± 0.5 > FFA (mumol/L) 328 ± 77 <

0.05 395 ± 78 <0.01 305 ± 71 > Total cholesterol (mmol/L) 5.8 ± 0.8 > 5.7 ± 0.9 > 5.5 ± 0.8(215) (185-245) > LDL cholesterol (mmol/L) 3.8 ± 0.7 <0.05 4.6 ± 0.5 <0.01

3.0 ± 0.5(115) > HDL cholesterol (mmol/L) 1.8 ± 0.2 <0.01 0.9 ± 0.3 <0.01 1.8 ± 0.3(70) > WBGD (mumol/kg FFM·min) 34.6 ± 1.1 <0.01 22.4 ± 0.4 <0.01 38.1 ± 1.6 >

> > THE PLASMA insulin-like growth factor I (IGF-I) concentration has been shown to decline with advancing age [1] ,[2] , but also to be influenced by sex steroids [3] , nutritional status [4] , and liver function [5] . More than 80% of plasma IGF-I circulates bound to IGF-binding protein-3 (IGFBP-3) and forms a large 150-kDa complex that cannot leave the circulation [1] ; thus, only the unbound form of IGF-

I is considered to be biologically active [6] . > > {BUT: " All subjects were normotensive, were taking no medications, were not smokers, and had no evidence of metabolic or cardiovascular disease. ...Subjects with a family history of noninsulin-dependent diabetes mellitus, obesity [body mass index (BMI), >30], or hypertension were excluded from the study. No woman was taking hormone replacement therapy before or during the study. " }> >

> 15. tti S, Barbesino G, Caterugli P 1993 Complex alteration of thyroid function in healthy centenarians. J Clin Endocrinol Metab 77:1130-1134 > > 16. Paolisso G, Tagliamonte MR, Rizzo MR, Manzella D, Gambardella A, Varricchio M 1998 Oxidative stress and advancing age: results in healthy centenarians. JAGS 46:833-838 > > 17. Paolisso G, Gambardella A, Ammendola S, D'Amore A, Balbi V, Varricchio M, D'Onofrio F 1996 Glucose tolerance and insulin action in healthy centenarians. Am J Physiol 270:E890-E896 > > 18. Paolisso G, Gambardella A, Ammendola S, Tagliamonte MR, Rizzo MR, Capurso A, Varricchio M 1997 Preserved antilipolytic insulin action is associated with a less atherogenic plasma lipid profile in healthy centenarians. J Am Geriatr Soc 45:1504-1509

[Guest guest]

All,

Here's what I gleaned from the article:

First, there's a pretty good definition of RQ and what it means here:

http://www.tiem.utk.edu/~gross/bioed/webmodules/respiratoryquotient.html

RQ can be used to determine your metabolic rate. It can also be used

somewhat to glean diet, although I haven't figured out yet how to

relate RQ to diet. Apparently metabolizing fats creates a higher RQ

than metabolizing carbs.

From the article: RMR, WHR, fat mass (FM), and %BF all decrease as

people get older.

RQ also decreases with age. So as we get older, our metabolic rate

slows down, we lose fat and girth, which probably includes LBM.

RQ is inversely proportional to WHR and is negatively correlated with

FFM as well. (So the smaller you are the higher your RQ).

This is for all subjects, so far.

For long lived subjects-- they have relatively higher RMR and RQ than

normal elderly subjects. So their metabolism has slowed down less.

They also have lower BMI, lower WHR, and lower FFM -- all indicative

of CR in my opinion.

So does this mean they eat relatively more fat than carbs? That

sounds backwards. I may be interpreting it incorrectly.

Diane

> Hi JW:

>

> I am having trouble figuring out the significance of this. Can you

> help me out, please?

>

> First, is RQ the ratio of CO2 breathed out to O2 breathed in? Or is

> it the ratio of CO2 produced by tissues to the O2 used by tissues?

> In other words is it in effect a measure of lung effectiveness? Or

> not?

>

> Second, is a high RQ 'good', or is it 'bad' or does it not matter?

>

> Third, what in your view are the principal things we should learn

> from this if we want to survive beyond 100?

>

> Or were you hoping we would be able to answer these same questions

> for you? ; ^ )))

>

> Thanks.