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mesmall
02-22-2001, 12:44 PM
Just going through some of the reader mail answered by Ellington Darden and found a interesting reply that stated 0.8 grams per kg of body weight was already double the USDA recommended amount for protein. From what I have seen around here people are saying around 1 to 2 grams of protein per POUND !!http://classicx.com/html/23fb.html

hemants
02-22-2001, 01:30 PM
The USDA has a recommended minimum of 6% of calories from protein; this is not a recommended level but a recommended minimum.

Anyhow, the level for health maintenance is not the same as the level for adding muscle mass and any excess will just be excreted in urine.

Mind you, kidney failure and osteoperosis are diseases that are linked to excess protein consumption.

Alex.V
02-22-2001, 02:15 PM
...but technically, if you take calcium supplements (protein digestion leeches calcium from the bones) and drink lots of water (To prevent nitrogen buildup in the kidneys from protein metabolism) you can avoid all these problems. I would say if you follow these two guildlines, you don't have to worry about overdosing. I'd say 1 gram/lb is good for strength athletes, but percentage wise that's not always that much. I eat about 2800 kcal/day. 160 grams of protein is only about 23%. Remember that, when you're eatin' large. ;)

Braveheart99
02-22-2001, 02:15 PM
In order to cause kidney problems you would have to eat a S!$t load of protein, I am talking in the ball park of 400-500g per day for a extented period of time.:eek:

Eating 1-2g per pound of body weight will not hurt your kidney.

later :cool:

hemants
02-22-2001, 02:26 PM
Belial - that's good advice :-)

Braveheart - it probably won't hurt in the short term but unless you know of some new studies to the contrary, it has been shown to be a factor in kidney failure which usually occurs later in life.

Big Worm
02-22-2001, 03:11 PM
Hemants,
It is not true that excess protein will be excreted in the urine. In fact if someone consumes excess protein the amino acids will be deaminated(strip of nitrogen containing group), the nitrogen will be excreted and the remaining carbon fragments will be converted to fat and stored. It is only the Nitrogen from the amino group that ends up in the urine. The deamination process produces ammonia which is converted to urea by the liver, transported to the kidneys and eventually excreted with the urine. But I think some fat storage is the price to pay in order to achieve a positive nitrogen balance.

YatesNightBlade
02-23-2001, 02:22 AM
Originally posted by hemants
Belial - that's good advice :-)

Braveheart - it probably won't hurt in the short term but unless you know of some new studies to the contrary, it has been shown to be a factor in kidney failure which usually occurs later in life.

where is your evidence for this ???? What references do you have ?

hemants
02-23-2001, 06:50 AM
Most of the info I have is from talking to my brother in law who is a Urologist.

There's a lot of stuff on the web but most of it is without reference to any specific journal with the exception of this article:

http://www.benbest.com/health/kidney.html

Highlights:

" [AMERCIAN JOURNAL OF KIDNEY DISEASE 27(5):652-662 (1996)] compared kidney patients on a low protein diet (0.73gm/kg/day) with patients on a very low protein diet (0.66 gm/kg/day). It was concluded that for every 0.2 gm/kg/day of protein increase there was a 29% GFR (Glomerular Filtration Rate) decline associated with a 41% prolongation in the time before the patients experienced renal failure."

"The kind of dietary protein may also be important. Subjects fed 90 grams of meat protein daily showed a significantly greater increase in GFR (stress on the
kidney) than was seen for subjects fed 90 grams of milk protein [CLIN. NEPHROL. 27(2):71-75 (1987)]. By contrast, a study with whey protein [NAHRUNG 42(1):12-15 (1998)] showed no significant effects on liver or kidney function. "

hemants
02-23-2001, 07:03 AM
Counterpoint:

Most of the studies of excess protein are probably done with patients with a sedantary lifestyle. The real question (to which I don't know the answer) is that if someone is working out and utilizing the protein intake for muscle growth, does this tax the kidneys or is it just the process of elimination of the excess, unutilized protein that is the culprit.

Also, most bodybuilders tend to restrict alcohol intake and drink a lot of water which should counterbalance some negative effects on the kidney.

Nevertheless, if we can figure out how much protein we need (at most) then it probably makes sense not to ingest much beyond that and we should be fine.

mesmall
02-23-2001, 07:54 AM
Nevertheless, if we can figure out how much protein we need (at most) then it probably makes sense not to ingest much beyond that and we should be fine.

Yes, that would be nice to know

Big Worm
02-23-2001, 07:58 AM
hemants,
to answer your question, it is only excess that puts strain on the kidneys. When amino acids are in excess they will be used for energy and not for other jobs(protein snythesis). The amino acids are deaminated producing ammonia(toxic) as a byproduct. The liver has to convert this to urea and pass it on to the kidneys. It is having to deal with this urea that can put strain on the kidneys but if there is no urea to be begin with(if the amino acids are never broken down) then there is no problem.

hemants
02-23-2001, 08:13 AM
Thanks Big Worm!

You certainly know your stuff. You a doctor?

Big Worm
02-23-2001, 08:27 AM
No, im not a doctor. I just happen to be studying nutritiion in college right now so this stuff is fresh in my head.

mesmall
02-23-2001, 10:53 AM
According to standard deviations, the 0.8 figure was twice as much as 98 percent of the population actually needed. The requirements of athletes and fitness-minded people were also considered in determining the guide number.

Does anyone know of any other scientific study to contradict or back this statement up?

Big Worm
02-23-2001, 10:55 AM
hey mesmall, check this link out;
http://www.i-a-r-t.com/articles/proparadox.html

hemants
02-23-2001, 11:50 AM
Big Worm,

Very interesting article.

On one hand it says that a high protein diet may increase the body's dependancy on that high level of protein (since it starts to squander resources)

On the other hand it talks about protein cycling.

Then he says "in summary ... 1.35g/kg of bodyweight" but doesn't say whether that requirement is for the average joe, a bodybuilder or both.

What's your take?

J-Flyer
02-23-2001, 11:50 AM
According to that study, Whey Protein has no effect on the kidney (if I read that correctly). I would think for any bodybuilder, the "EXCESS" protein in their diet would come from Whey which has no effects. Am I missing the arguement here?

If the article meant a diet of only Whey protein - well, I would think that is impossible; as you can find small amounts of protein in everyday food.