Protein, its sources and longevity

[Guest guest]

Hi All,

I was pleased to find the below pdf-

available report that all-cause mortality

changes little with the level of protein in the diet

in a 15-year-prospective study.

The BMIs of the postmenopausal women were,

in increasing quintiles of protein:

Body mass index, kg/m^2 = 25.2, 25.6, 25.7, 25.9, 26.7.

So, although caloric intakes were not given, the

subject BMIs were low (and in the Iowa Women¡¯s

Health Study).

The risk of all-cause mortality on the same

basis as BMI above, was:

Multivariable risk ratio = 1, 0.95, 0.81, 0.84, 0.99;

confidence interval = 1.38 0.67; p = 0.71.

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* Protein intake expressed as percentage of energy.

Adjusted for age, total energy, saturated fat, polyunsaturated

fat, monounsaturated fat, and trans-fat

(expressed as percentage of energy and categorized into quintiles).

Also adjusted for total fiber, dietary cholesterol, dietary

methionine (all quintiles are based on energy-adjusted

values), alcohol (¡Ü14 g/day vs. >14 g/day), smoking (never, former,

current), activity level (active vs. not active),

body mass index (<21.0, 21.0¨C22.9, 23.0¨C24.9, 25.0¨C28.9, ¡Ý29.0),

history of hypertension, postmenopausal

hormone use, multivitamin use, vitamin E supplement use, education

(high school education or less vs. post-high

school), and family history of cancer.

The improved heart disease death with lower protein

was compensated by a statistically not significant

higher cancer death.

Kelemen LE, Kushi LH, s DR Jr, Cerhan JR.

Associations of dietary protein with disease and mortality in a

prospective

study of postmenopausal women.

Am J Epidemiol. 2005 Feb 1;161(3):239-49.

PMID: 15671256 [PubMed - in process]

Some weight loss diets promote protein intake; however, the

association of

protein with disease is unclear. In 1986, 29,017 postmenopausal Iowa

women

without cancer, coronary heart disease (CHD), or diabetes were

followed

prospectively for 15 years for cancer incidence and mortality from

CHD, cancer,

and all causes. Mailed questionnaires assessed dietary, lifestyle,

and medical

information. Nutrient density models estimated risk ratios from a

simulated

substitution of total and type of dietary protein for carbohydrate

and of

vegetable for animal protein. The authors identified 4,843 new

cancers, 739 CHD

deaths, 1,676 cancer deaths, and 3,978 total deaths. Among women in

the highest

intake quintile, CHD mortality decreased by 30% from an isoenergetic

substitution of vegetable protein for carbohydrate (95% confidence

interval

(CI): 0.49, 0.99) and of vegetable for animal protein (95% CI: 0.51,

0.98),

following multivariable adjustment. Although no association was

observed with

any outcome when animal protein was substituted for carbohydrate, CHD

mortality

was associated with red meats (risk ratio = 1.44, 95% CI: 1.06, 1.94)

and dairy

products (risk ratio = 1.41, 95% CI: 1.07, 1.86) when substituted for

servings

per 1,000 kcal (4.2 MJ) of carbohydrate foods. Long-term adherence to

high-protein diets, without discrimination toward protein source, may

have

potentially adverse health consequences.