Re: Re: Resting metabolic rate and respiratory quotient in human longevity - BMI vs CR

[Guest guest]

Doug Shrecky's website set me off on the BMI vs CR issue.

"Caloric Restriction Does not Slow Ageing in Humans"

http://www.geocities.com/longevityrpt/lr65.htm#Caloric%20Restriction%20Does%20not%20Slow%20Ageing%20in%20Humans

I wondered about:

"Lower BMI is associated with reduced mortality in young and middle-aged humans. If caloric restriction retards the rate of aging and extends maximum life span in humans one must expect that a lower BMI would be significantly associated with reduced mortality in aged humans. If such an significant association is not found then caloric intake is not operative in modifying the rate of aging in humans and life spans beyond 120 will not be possible by reducing caloric intake."

{BMI is related to mortality. Mortality increases above a certain level of BMI.

CR is related to lifespan. We think we can lengthen lifespan using CR.

It has not been shown we can lengthen lifespan by lowering BMI. Actually a "U" curve.

And we also know that lowering blood pressure down to 120/80 lowers mortality, but it doesn't lengthen lifespan if we lower it further.

ref:

bmj thin folks:

Table 2 Number of deaths and death rate ratios (95% CI) by BMI category among all subjects

Cause of death

<18

18<20

20<22 (ref)

22<24

24<26

26<28

28+

All causes

2.07

1.24

1

1.12

1.29

1.15

1.28

Circulatory diseases

2.48

1.12

1

1.16

1.39

1.56

2.12

Ischaemic heart disease

2.49

0.99

1

1.36

1.28

1.84

2.29

All other causes

2.63

1.87

1

1.38

1.1

1.57

0.66

All malignant neoplasms

1

1.11

1

0.97

1.23

0.66

0.81

Respiratory diseases

3.69

1.22

1

1.13

1.47

0.66

0.43

Cerebrovascular disease

3.47

1.66

1

1.52

1.5

1.41

1.93

USA:

http://content.nejm.org/cgi/content/full/341/15/1097?ijkey=7675ea21ba89b60efafb3ab723a4c23bff195fe4

"The optimal body-mass index for longevity fell between 20.5 and 24.9 for men and women of all ages. These data offer support for the use of a single recommended range of body weight throughout life. "

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?Third, what in your view are the principal things we should learn from this if we want to survive beyond 100?