Re: Re: Back to Methionine/ chicken and fish

[Guest guest]

Here is Rodney’s post that I was alluding to (#26058), I underlined Rodney’s conclusion below:

Re: Red Meat Heme > Cancer

Hi folks:

Checking PubMed for studies related to the one Jeff posted (below),

shows this one, which seems interesting:

Extracts from abstract:

" We examined the relationship between intakes of ...... meats,

vegetables, and fruits [and] levels of oxidative DNA damage ...... . "

" Intakes of raw and cooked vegetables were examined separately. Meat

intake was examined by type of meat (pork, beef, fish, chicken) and

by cooking temperature. "

" The model that best explained DNA damage ...... included the intake

of cooked vegetables and the sum of beef and pork intake. This model

accounted for 85% of the variation in DNA damage levels. "

" Preliminary results are suggestive of a positive association of DNA

damage with beef and pork intake and a negative association with

cooked vegetable intake. "

Eighty-five percent is a high number! The findings mentioned in the

abstract are not very surprising. But, while I haven't seen the full

text, the abstract implies that consumption of fruit, fish, chicken

and *raw* vegetables are neither positively nor negatively associated

with DNA damage - which IMO is REALLY interesting.

FULL ABSTRACT:

" Oxidative DNA damage levels in blood from women at high risk for

breast cancer are associated with dietary intakes of meats,

vegetables, and fruits. "

Djuric Z, Depper JB, Uhley V, D, Lababidi S, o S,

Heilbrun LK.

Barbara Ann Karmanos Cancer Institute, Wayne State University,

Detroit, Mich., USA.

OBJECTIVE: We examined the relationship between intakes of specific

foods--namely, meats, vegetables, and fruits--with levels of

oxidative DNA damage in women consuming their own usual diet or a

diet low in fat. DESIGN: Blood was obtained from women who had been

assigned randomly to a low-fat or nonintervention diet for 3 to 24

months. Levels of 5-hydroxymethyluracil, a type of oxidative DNA

damage, were determined. Diet data were obtained from 3-day food

records. SUBJECTS/SETTING: The 21 women were participating in an

outpatient clinic. All the women were healthy but had a first-degree

relative with breast cancer. INTERVENTION: The intervention was a

self-selected diet with a goal of 15% of energy from fat. MAIN

OUTCOME MEASURES: Existing data on oxidative DNA damage levels were

evaluated for possible relationships to foods eaten. Intakes of raw

and cooked vegetables were examined separately. Meat intake was

examined by type of meat (pork, beef, fish, chicken) and by cooking

temperature. STATISTICAL ANALYSES: Initial univariate analyses relied

on Spearman rank correlations of each food item with DNA damage.

Further analyses of the data were performed with univariate and

multivariate weighted least squares regression models. RESULTS: The

model that best explained DNA damage levels was a bivariate

regression model that included the intake of cooked vegetables and

the sum of beef and pork intake. This model accounted for 85% of the

variation in DNA damage levels among women. Preliminary results are

suggestive of a positive association of DNA damage with beef and pork

intake and a negative association with cooked vegetable intake.

APPLICATION: These observations, if confirmed in larger studies,

suggest specific dietary changes to reduce oxidative DNA damage

levels and possibly cancer risk. "

PMID: 9597024

Rodney.

From: Francesca Skelton <fskelton@...>

Reply-< >

Date: Tue, 01 Jul 2008 19:29:10 -0400

support group < >

Conversation: [ ] Re: Back to Methionine/chicken and ish

Subject: Re: [ ] Re: Back to Methionine/chicken and ish

As I recall Rodney posted a study a few months ago that eating chicken and fish did not cause some unfavorable reaction(s) in the body that other proteins (milk, red meat) caused. Perhaps that’s a clue to fish eating by some of the world’s longest lived people. Also there are so many benefits to eating fish that perhaps the benefits outweigh any drawbacks. (Sounds to me similar to the controversy we have over red wine –i.e. Drinking several glasses a day in a couple of studies let to longer lives).

If anyone can dig up that post (Rodney?) please do. Perhaps it too belongs in the files.

From: jwwright <jwwright@...>

Reply-< >

Date: Tue, 1 Jul 2008 17:23:44 -0700

< >, Rodney <perspect1111@...>

Subject: Re: [ ] Re: Back to Methionine

The part that is always left out is cysteine which is " sister " part of the

methionine loop.

The other thing is the longest lived, the Japanese, supposedly eat lot of

fish.

Regards

[ ] Re: Back to Methionine

Hi Tony:

Yes, I agree. In fact I discussed this very point in the piece I put in the

files on protein restriction:

'CRON Science' ...... 'DOES CR WORK THROUGH PROTEIN RESTRICTION?'

http://f1.grp.fs.com/v1/wIxqSMP3EtihIwkqJuGMrZ5iYgdg-0-qWaGFLHJYgryHCfB

-7XXBj1GTPH2Sr6t4tcdfY8MD5SqCRQPoes2h/CRON%20SCIENCE/Does%20CR%20Work%20thro

ugh%20Protein%20Restriction%3F

or: http://snipurl.com/2san9

The last part of which reads:

====================

" ............. BUT APART FROM THE BENEFIT OF CALORIC RESTRICTION, THE

ABOVE HAS YET BEEN CONCLUSIVELY DEMONSTRATED.

" Indeed there is some evidence which does not fit well with the methionine

hypothesis. For example, the most prolific sources of methionine in the

human diet are animal products. So, if the hypothesis is correct,

vegetarians and vegans should enjoy significantly extended lifespans

compared with meat eaters.

" While vegetarians and vegans on diets containing all essential nutrients

are healthy, PMID: 16441942, referenced by Jeff Novick in post #24225,

suggests their lifespans are not in fact longer than those of similarly

health-conscious meat eaters.

" So the evidence with regard to protein and methionine restriction is not

entirely one-sided.

" As always, we each have to make up our own minds where to place our bets,

based on our personal assessment of the evidence. Naturally, sometimes when

one bets, one loses. "

====================

So we still do not know to what extent this will/may affect the aging rate

in humans. That said, reducing one's intake of MET to around the RDA for

it (perhaps one gram a day) does not seem likely to have any downside. (My

opinion only, of course)

Rodney.