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I've read that we should be careful how much protein we intake. 30grams or so at a time, because this is all that the liver can deal with.

But if we want to consume the amounts of protein that we do, for example 1 and a half g per pound of body weight, which in my case is approx 200g, then how do we do this safely?

How much time does the liver need to do it's stuff?

Thanks for taking the time to read this. I'm aware that I ask some very basic and sometimes strange quetions.

Thanks again.

Not an easy question to answer.

Here was the previous discussion.

http://exrx.net/forum/viewtopic.php?t=388

Well, the link VOK posted was certainly a good rehash with several points of view. I'm just going to mention on the liver question. Frankly, I've never heard of excess protein affecting the liver. Kidneys, yes, but I've also heard of studies that seem to substantiate that it takes a LOT of excess protein to cause problems, way in excess of 30 grams. I'm not even sure where that number came from. I think it's based on a normal "average" person that may not even work out Not sure. I do know that it's probably close to being accurate. However, I wouldn't worry if occasionally you sit down and have 50 gr worth in a meal.I know Dr Sears of the Zone recommends protein to be in accordance with lean bodyweight, and for anyone doesn't ecommend much more than 5 zone blocks of it (approx 35 gr), but, again, I wouldn't lose any sleep if you occasionally go over that
Tim

Got curious and did a search on the effects of high protein diets on the liver.
http://www.sportsnutritionsociety.org/s ... 1-2004.pdf

Wow. Thanks VoK

Good article. It goes to show that a lot of research is flawed and a keen eye for detail is necessary to make any assumption.

However, I feel that the gist of the article is a little too "protein positive." It clearly leans towards the idea that there really is no such thing as excessive protein consumption. But I don't think that's the message that should be given out.

Rather, I think the message should be that one should not worry about excessive protein consumption, but one should not go out of their way to consume as much protein as possible.

One thing you should keep in mind, is you can only use so much at a time. The extra just gets converted to energy though. So it's ok to go over. Some people may only be able to use 30 grams at a time.

Yep, VOK, I agree completely.Shoot for around 25-35 gr/setting, but don't be overly concerned if it goes a bit high at times, and don't feel the need to overload on protein.
Tim

If I had to eat protein in 30 gram bits, that would take me 7 or 8 meals to get what I needed. I'd have to quit my job just to focus on protein intake. lol

I usually go for 40 to 50 g a meal.

The 30 gram limit seems awfully low. If I have a post workout meal of say baked beans on 3 slices of whole wheat toast and a half litre of milk my protein works out to something like 50 grams and that is not a huge meal.

That is usually only true of smaller people. Most people can use more. Nothing wrong with excess protein anyway. I haven't seen this proven anywhere, but my theory is the bigger you are the more you can use at a time. I have had 75 grams at once before. I'm not sure if I used it all for building or supporting muscle or not. It's a good way to fill up though. A lot of calories are wasted converting protein to energy. It's a good way to get full. make sure you have your protein needs and plenty of calories, but not get fat.

I am no supporter of protein supplementation but Im not opening that can of worms. Instead just wanted to respond to a point made...."A lot of calories are wasted converting protein to energy. It's a good way to get full. make sure you have your protein needs and plenty of calories, but not get fat."

Bugger all energy is used when converting proteins to energy. You get 5.65kcal energy yield per gram of protein when broken down in a lab and the energy yield in the body is about 5.20kcal. The energy used to convert nitrogen to urea only costs you 8%. A healthy body only uses about 5-10% of total energy expenditure via protein even during exercise which is why it is usually ignored in expenditure estimates. The fact is that if you ingest a lot of protein your body will not go out of its way to utilise it as a source of energy. It will get used for repair and regrowth certainly but otherwise will be ignored.

I don't see too many people eating half of a hamburger at a time. (A doctor told me once to split a burger, because it's too much protein to eat at once.)

I'd say I eat 40 g of protein at a meal. Unless it's steak or something, in which case who cares how much protein it is, it tastes good!

no ur supposed to eat 1g/pound of bw.

_________________
Muhammad

Age: 15 Height: 5'9'' Weight: 153 lbs

Part of the problem with any type of scientific study that encompasses such a large number of variables as the human body and human culture is that in order to study one aspect you much hold constant everything else. Or at the very least you must conduct the experiment using a matrix to control those variables you wish to study. In either case, there are so many possiblities left open that each study can offer at best a narrow glimpse into the whole.

As such, I tend to take scientific studies with a tablespoon of salt. They should be taken within their own context and not extrapolated to imply conclusions that they cannot support. We should look to balance real-world results with scientific information. These two realms should be bashed together often to ensure that they both make good sense.

Science is the belief in the ignorance of experts. -- Richard Feynman