I am taking a nutrition class this summer and we just got done studying proteins. In class the instructor talked about how excess protein, beyond requirement, is stored as fat, similar to carbs. But protein unlike carbs is not stored in reserves. So excess protein (nitrogen) is excreted through the kidneys.
My question is: Do we really need 300g+ of protein a day, when most of it will just be pissed out anyway? And to think about all that strain on the kidneys, is it worth it? I am starting to think that 1g/lb of bodyweight would be more than enough.
[quote]TravisCS84 wrote:
I am taking a nutrition class this summer and we just got done studying proteins. In class the instructor talked about how excess protein, beyond requirement, is stored as fat, similar to carbs. But protein unlike carbs is not stored in reserves. So excess protein (nitrogen) is excreted through the kidneys.
My question is: Do we really need 300g+ of protein a day, when most of it will just be pissed out anyway? And to think about all that strain on the kidneys, is it worth it? I am starting to think that 1g/lb of bodyweight would be more than enough.[/quote]
What kind of nutrition class? Pretty much most of professors are idiots when it comes to nutrition. They’re stuck in the past and haven’t really got caught up. That’s a major reason why I switched from nutrition to biochemistry. Too much political bullshit to deal with. Everything is based on ADA (american dietetic association) which is mostly crap. As for the protein requirement, do some reading on lemmon’s studies. It’s around 1-1.25g of protein per lbs of lean bodyweight. The bigger you are, the more protein you have to take in so in a way Im glad im only 175 lbs. Sometimes i get tired of trying to get to 175g a day so that’s why I don’t do bodybuilding stuff these days. Just mostly powerlifting or athletic based program. Anything over 1.5g per lbs of lean muscle might be overkill unless you’re taking steroid or prohormone or others which speed up protein synthesis where you can add more protein to take advantage of it. You’d put on more muscles.
The class, believe it or not, is pretty cool and the teacher is real cool, pretty open minded and not your straight up FDA or USDA food pyramid by the books kind of teacher. She told us that her graduate work thesis was studying competitive bodybuilders and recreational bodybuilders and the health effects of their protein intake.
She basically said that long term wise, 200% and over of what the RDA (which is 0.8g/kg bodyweight) is too hard on the kidneys. Plus the fact that the body can’t absorb all the protein, it can be stored as fat.
The more I think about it, the more I am persuaded. What does everyone else think? I would love to hear some other opinions. I know that a lot of guys on this site recommend 1.5-2.0 g/lb no matter what.
Hmm… don’t really have an answer to your question, but I do have a few comments.
I was under the impression that everything in excess, whether carbs, fats, or proteins are either stored or excreted.
When I was reading and learning about weightlifting for the first time, I was always told to drink more water and more frequently. Also, to minimize protein intake to around 40g per meal. This was to make it easier on the kidneys I always thought.
Last comment. Excess carbs are held in reserve as fats, while not taxing on the kidneys, leads to other problems no?
This easily convinced me that my 350g of protein a day is worthwhile. If you stil aren’t convinced after reading that article I’ll just force feed you egg whites instead…
What you don’t understand but need to is that excess of anything is stored as fat, and as a matter of fact, if you have excess amounts of equivalent amounts of carbs/protein, more carbs will be stored as fat than protein.
Evilmage:
Carbs fill the blood which is then carried to the cells to be used as energy. After all the carbs that are needed are utilized, excess carbs are stored as glycogen in the muscles and liver. After those are filled up then carbs are stored as fat. Protein has many important roles: growth, antibodies, transportation, energy (if necessary), etc. After that protein is stored as fat.
Has anyone actually seen any evidence that a healthy person can actually suffer kidney damage at all just by eating protein?
I don’t mean evidence such as raised levels of markers which indicate the kidney is having to process protein, but evidence that indicates damage?
I’m no expert, but most of the things I recall reading talk about elevated levels of whatnot, which is also elevated in people suffering from various diseases.
I mean, do we sit around saying, jeez, don’t think tooo much… the brain will have to work harder and end up getting hurt! Are the kidneys wussy organs or something? I mean, is protein worse than alcoholism, smoking, being overweight and sedentary? Do they have no ability to recover if they have been stressed?
Rant rant rant. Rant. Seriously though, point me to something if its out there.
jcv423:
By long term she meant lifestyle, and our lifestyle is eating lots of protein.
Vroom:
I wouldn’t compare “protein binging” to drinking or smoking. But I would imagine that working the kidneys overtime to excrete all that nitrogen could have the potential to be harmful, but I may be wrong.
I asked one of the nephrologists (kidney docs) who works at the University of Pittsburgh about large amounts of protein being harmful to the kidneys. His reply was that there was no evidence that “too much” protein was harmful to healthy people. He said that the main reason that he restricts protein in patients with established kidney problems is not because it is harmful for their kidneys, but because if they eat large amounts of protein they accumulate larger amounts of protein breakdown products which is uncomfortable for them (since they cannot excrete them as effectively).
RDA’s and other studies looking at “ideal” amounts were historically meant to (and currently are often meant to):
Define MINIMUMS to PREVENT DISEASE.
Often done on the sedentary, “average” person and not on the athlete or active exerciser (even though this is changing).
When a person like your instructor (who sounds competent) states a “fact”…you HAVE to ask are these amounts meant as MINIMUMS to prevent disease…and does this hold true for the person wanting to add Muscle Mass?
(By the way…more and more studies are coming out indicating that the active person/athlete/Musclehead needs more protein than these amounts indicated in Nutrition Text).
[quote]ScottL wrote:
I asked one of the nephrologists (kidney docs) who works at the University of Pittsburgh about large amounts of protein being harmful to the kidneys. His reply was that there was no evidence that “too much” protein was harmful to healthy people. He said that the main reason that he restricts protein in patients with established kidney problems is not because it is harmful for their kidneys, but because if they eat large amounts of protein they accumulate larger amounts of protein breakdown products which is uncomfortable for them (since they cannot excrete them as effectively).[/quote]
Scott’s absolutely right, and that would not be the only inconvenient one would encounter. Even heathly bodybuilders could get drawbacks from prolonged protein overconsumption.
High protein diets causes accumulation of toxic metabolites like ammonia, causing you among other things to sweat with a stronger smell (in other words, you and your workout clothes will most likely stink).
High protein diets are also extremely dehydrating and, according to some researchers, can lead you in the long term (not that long) to become exceedingly efficient at breakingdown proteins by generating by default a more suitable ammount of protein-metaolism enzymes than what one normally has.
In turn, your excess consumption, eventually becomes your actually daily requirement because you’ll just need that huge amount of protein in order not to fall into muscle catabolism.
On the other hand, it has been demonstrated(Fu** I hate using this word) in quite a few studies that short term excess portein consumption leads to greater muscle growth. I suggest you look up articles from Torbjorn Akerfeldt about protein consumption cycling…he’s got a very interesting theory about how to benefit short term high protein diets without the long term possibly negative effects…
The question of how much protein is “too much” brings to mind another question. Too much for what? If we’re talking about kidney damage, I’m quite sure that not one person will be able to provide any evidence. This is not to say that it is impossible, but there is no scientific evidence to support this claim in healthy individuals (to my knowledge).
Protein in excess of CALORIE requirements will be stored as fat as will carbs and fat. For example, if you were consuming a starvation diet (~1000cals/day) it would be unlikely that your protein intake (even if it was above your requirements) would be stored as fat. If you are overeating ANY excess nutrients could be stored as fat. It just so happens that since protein has a higher thermogenic effect of feeding you could eat more total kcals from protein before it is stored as fat.
Just for reference, Lemon & Tarnopolsky have suggested a need for 1.2-1.5g per KILOGRAM of BODYWEIGHT. That means a 200lb guy needs about 140g per day. I’m not saying they’re correct. It was just a misquote on the amount.
Protein in excess of CALORIE requirements will be stored as fat as will carbs and fat. For example, if you were consuming a starvation diet (~1000cals/day) it would be unlikely that your protein intake (even if it was above your requirements) would be stored as fat. If you are overeating ANY excess nutrients could be stored as fat. It just so happens that since protein has a higher thermogenic effect of feeding you could eat more total kcals from protein before it is stored as fat.
[/quote]
Very true. But replacing carbs by protein in an under-maintenance-level diet would probably affect performance for proteins don’t make much of a fuel compared to carbs. Performance would be affected, not to mention mood and brain function. If you don’t supply enough glycogen to the brain, it’ll have to resort on using ketonic bodys, which is a waste by product of fat metabolism.
And as I mentionned in a previous post, someone constantly functionning on high proteins & low carbs diets would eventually begin to decrease its carb-digesting enzymes(“Amylase Pancreatique”, for instance, sorry I forgot what was the english name for it) and begin to increase it’s protein digesting enzymes. That would mean that if that someone was to go back on a regular diet with normal protein and carbs ratio, he’d be more likely to either put on some fat or start catabolizing…or both.
Very true. But replacing carbs by protein in an under-maintenance-level diet would probably affect performance for proteins don’t make much of a fuel compared to carbs. Performance would be affected, not to mention mood and brain function. If you don’t supply enough glycogen to the brain, it’ll have to resort on using ketonic bodys, which is a waste by product of fat metabolism.
And as I mentionned in a previous post, someone constantly functionning on high proteins & low carbs diets would eventually begin to decrease its carb-digesting enzymes(“Amylase Pancreatique”, for instance, sorry I forgot what was the english name for it) and begin to increase it’s protein digesting enzymes. That would mean that if that someone was to go back on a regular diet with normal protein and carbs ratio, he’d be more likely to either put on some fat or start catabolizing…or both.[/quote]
No argument here. I’m personally not an advocate of high (i.e., 2g/lb) protein diets even while dieting because of the very enzyme changes you mentioned. Upregulation of the protein digesting enzymes can cause catabolism if protein levels are decreased upon returning to a normal diet. That said, an increase in total calories (to maintenance or above) could prevent or minimize such a loss even if protein intake is lower. Your point about carbohydrate enzymes I did not know…but it makes sense.
Slightly off topic but…if this is true, "High protein diets are also extremely dehydrating and, according to some researchers, can lead you in the long term (not that long) to become exceedingly efficient at breakingdown proteins by generating by default a more suitable ammount of protein-metaolism enzymes than what one normally has. "
[quote]GJG wrote:
Slightly off topic but…if this is true, "High protein diets are also extremely dehydrating [/quote]
Drink lots of water.
This is not rocket science. If you eat lots of protein and few carbs, the body adjusts (there are limits of course to how far it can adjust) amd makes more enzymes to digest protein and fewer enzymes to digest carbohydrates.
Travis, your prof studied this in bodybuilders? Cool, but how come no is asking for more info? Hook us up with whatever she told you, and find out where it was published (what’s her last name?).
My fave study of all time used the equivalent of 20000g of protein a day in rats with 1/3 of ONE kidney function. The excess protein caused mild problems… can you IMAGINE?
Well, I furthered questioned my prof. about it, and it turns out her thesis was not solely on protein intake, but more on the techniques bodybuilders used to control weight (pre-comp dehydration, etc) and she looked at how other guys would try to adopt these techniques to look good for the beach. Anyway, the more I talked to her about it, the less it had to do with protein.
She said she would continue to look for studies on excess protein and kidney damage and send them to me. As of right now, she sent me one: European Journal of Clinical
Nutrition 50 (1996): 734-740 Title: Effect of Chronic dietary protein intake
on the renal function in healthy subjects. Author: Brandle, Sieberth and
Hautmann.
I haven’t even read it yet (haven’t made a trip to the school library yet to even look.)
I’m with the rest of T-nation, I am not convinced that an active healthy male like myself that drinks plenty of water should suffer from kidney damage. BTW Dave, her name is Raina Childers, MS, RN, and I believe she has a few articles in the ST Louis Post-Dispatch, but not the one on bodybuilders.