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TPT
07-26-2009, 12:12 AM
so we're all on high protein diets. but, is chronic excess dietary protein safe?

well over the years two controversial issues have arisen within the literature: renal disease and bone loss.

yeah, you guys better be concerned! lol.

anyway, the following paper on bone loss caused considerable uproar when it was published. take a read. its still interesting. ome people believe high protein diets causes increased calcium loss through urine because of acid content.


http://jn.nutrition.org/cgi/reprint/128/6/1051
Excess Dietary Protein Can Adversely Affect Bone


Manuscript received 27 January 1998. Revision accepted 9 March 1998.

Uriel S. Barzel and Linda K. Massey*,

Division of Endocrinology and Metabolism, Department of Medicine, Montefiore Medical Center and The Albert Einstein College of Medicine, Bronx, NY 10467 and * Food Science and Human Nutrition, Washington State University, Spokane, WA 99201 The average American diet, which is high in protein and low in fruits and vegetables, generates a large amount of acid, mainly as sulfates and phosphates. The kidneys respond to this dietary acid challenge with net acid excretion, as well as ammonium and titratable acid excretion. Concurrently, the skeleton supplies buffer by active resorption of bone. Indeed, calciuria is directly related to net acid excretion. Different food proteins differ greatly in their potential acid load, and therefore in their acidogenic effect. A diet high in acid-ash proteins causes excessive calcium loss because of its acidogenic content. The addition of exogenous buffers, as chemical salts or as fruits and vegetables, to a high protein diet results in a less acid urine, a reduction in net acid excretion, reduced ammonium and titratable acid excretion, and decreased calciuria. Bone resorption may be halted, and bone accretion may actually occur. Alkali buffers, whether chemical salts or dietary fruits and vegetables high in potassium, reverse acid-induced obligatory urinary calcium loss. We conclude that excessive dietary protein from foods with high potential renal acid load adversely affects bone, unless buffered by the consumption of alkali-rich foods or supplements.

Key words: humans, protein, bone, acid, potassium.

The Journal of Nutrition Vol. 128 No. 6 June 1998, pp. 1051-1053
Copyright 1998 by the American Society for Nutritional Sciences


since then many other studies and theories have come up.
what do you guys think?

the following is the position of the international society of sports nutrition. http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=2117006#B19
Position Statement
The following seven points related to the intake of protein for healthy, exercising individuals constitute the position stand of the Society. They have been approved by the Research Committee of the Society. 1) Vast research supports the contention that individuals engaged in regular exercise training require more dietary protein than sedentary individuals. 2) Protein intakes of 1.4 – 2.0 g/kg/day for physically active individuals is not only safe, but may improve the training adaptations to exercise training. 3) When part of a balanced, nutrient-dense diet, protein intakes at this level are not detrimental to kidney function or bone metabolism in healthy, active persons. 4) While it is possible for physically active individuals to obtain their daily protein requirements through a varied, regular diet, supplemental protein in various forms are a practical way of ensuring adequate and quality protein intake for athletes. 5) Different types and quality of protein can affect amino acid bioavailability following protein supplementation. The superiority of one protein type over another in terms of optimizing recovery and/or training adaptations remains to be convincingly demonstrated. 6) Appropriately timed protein intake is an important component of an overall exercise training program, essential for proper recovery, immune function, and the growth and maintenance of lean body mass. 7) Under certain circumstances, specific amino acid supplements, such as branched-chain amino acids (BCAA's), may improve exercise performance and recovery from exercise.






ill be back to chat more.

Frosty
07-26-2009, 01:07 AM
The Rapist, I actually was reading studies that were showing the complete opposite, that in fact people that ate higher protein diets had better bone mass. "higher" meaning kinda low by our standards, though. I really forget in the papers what reason this might be caused by and right now after working over 12 hours I'm not in the mood to browse through research papers lol.

If you ate your vegetables would you even have an "acid problem"? Would the calcium content of taking in protein shakes change this? What about when you get enough vitamin D like we should?


Although for longevity I do believe in higher fat and lower protein. Protein increases IGF-1 which isn't good news in terms of cancer.

RDFinders
07-26-2009, 01:12 AM
interesting you posted this as i have been reviewing some articles and other readings on excessive protein intake.

i will say, i had a male client who had the bone density of a 65 yo post-meno female. he chronically dieted and only followed high protein diets for years. had a hard time trying to change his mind otherwise on lessening the protein in his diet.

on the renal disease - there is much debate about it. healthy kidneys do exp more vein/artery dilation as a result of trying to filter the excess urea that is produced. but it hasn't been proven that this increased blood flow in this area actually causes renal damage. but then the studies i have looked were done for any significant length of time period to see if excessive protein intake was kept constant, if the dilation became permenant or if microscopic tears were produced and if that caused a leakage of proteins in the urine.

Frosty
07-26-2009, 01:29 AM
Yeah and just because the kidneys work harder doesn't necessarily mean it's harmful (although is it healthy?). If you eat more food your digestive system has to work harder, but that isn't harmful (let's say 2000 cal vs. 3000 cal, nothing ridiculous here).

In terms of longevity, is a lower protein, higher fat diet healthier? Assuming we're talking healthy food I would probably say the answer is yes. Less insulin, less work for the digestive system as well as other body systems, and lower IGF-1 levels. Now take it another step further. If you ate a higher fat lower protein diet but then cut calories keeping the micronutrients the same, that's probably even healthier because there is less strain on the body, even lower insulin, etc.


But you know what? Who wants to live like that!!! I'm a meat eater through and through and I feel best on a high meat diet. Maybe once I'm old I'll start changing the diet so it's geared more towards longevity.

TPT
07-26-2009, 01:42 AM
The Rapist, I actually was reading studies that were showing the complete opposite, that in fact people that ate higher protein diets had better bone mass. "higher" meaning kinda low by our standards, though. I really forget in the papers what reason this might be caused by and right now after working over 12 hours I'm not in the mood to browse through research papers lol.

If you ate your vegetables would you even have an "acid problem"? Would the calcium content of taking in protein shakes change this? What about when you get enough vitamin D like we should?


Although for longevity I do believe in higher fat and lower protein. Protein increases IGF-1 which isn't good news in terms of cancer.

you aint right- at all. lmao.

anyway, the response paper to barzel and massey (1998) argued the opposite. http://jn.nutrition.org/cgi/reprint/128/6/1054 i.e., as long as we received the right amounts of calcium, problems due to calcium excretion would be ameliorated.
Excess Dietary Protein May Not Adversely Affect Bone


Manuscript received 27 January 1998. Revision accepted 9 March 1998.
Robert P. Heaney

Creighton University, Omaha, NE 68178 Too little protein is always harmful for the skeleton. Increasing dietary protein increases endogenous calcium excretion. The ability to adapt depends upon the adequacy of an individual's calcium intake. At a population level, the effect of protein is often minimized because calcium intake rises with increasing protein intake. A dietary calcium-to-protein ratio http://jn.nutrition.org/math/12pt/normal/ge.gif20:1 (mg:g) probably provides adequate protection for the skeleton. Excess protein will not harm the skeleton if the calcium intake is adequate.
Key words: protein, calcium, bone, humans.

The Journal of Nutrition Vol. 128 No. 6 June 1998, pp. 1054-1057
Copyright 1998 by the American Society for Nutritional Sciences


vegetables should help as alkali buffers. fruits too. http://ddr.nal.usda.gov/bitstream/10113/67/1/IND20581001.pdf

as far as longevity, high protein intake at older ages certainly might be big problem.

Frosty
07-26-2009, 02:04 AM
s far as longevity, high protein intake at older ages certainly might be big problem.

Especially since as you age digestive strength weakens, and meats require the most work to digest properly. Eating a bunch of meat isn't going to be healthy if the body lacks the capacity to produce enough stomach acid to break it down.

TPT
07-26-2009, 11:20 AM
interesting you posted this as i have been reviewing some articles and other readings on excessive protein intake.

i will say, i had a male client who had the bone density of a 65 yo post-meno female. he chronically dieted and only followed high protein diets for years. had a hard time trying to change his mind otherwise on lessening the protein in his diet.

on the renal disease - there is much debate about it. healthy kidneys do exp more vein/artery dilation as a result of trying to filter the excess urea that is produced. but it hasn't been proven that this increased blood flow in this area actually causes renal damage. but then the studies i have looked were done for any significant length of time period to see if excessive protein intake was kept constant, if the dilation became permenant or if microscopic tears were produced and if that caused a leakage of proteins in the urine.


rdfinders, it is hard to discriminate causal relations with older patients since they usually have comorbidities including correlating osteoporosis, calcium deficiencies, etc.

though the literature is sketchy regarding renal failure and high protein, i dont need studies to tell me to be careful with high protein intake in older ages.

do you think as we age we have reduced renal functions? e.g., the suceptibiltiy of lower blood ph.

TPT
07-26-2009, 11:28 AM
Yeah and just because the kidneys work harder doesn't necessarily mean it's harmful (although is it healthy?). If you eat more food your digestive system has to work harder, but that isn't harmful (let's say 2000 cal vs. 3000 cal, nothing ridiculous here).

In terms of longevity, is a lower protein, higher fat diet healthier? Assuming we're talking healthy food I would probably say the answer is yes. Less insulin, less work for the digestive system as well as other body systems, and lower IGF-1 levels. Now take it another step further. If you ate a higher fat lower protein diet but then cut calories keeping the micronutrients the same, that's probably even healthier because there is less strain on the body, even lower insulin, etc.


But you know what? Who wants to live like that!!! I'm a meat eater through and through and I feel best on a high meat diet. Maybe once I'm old I'll start changing the diet so it's geared more towards longevity.



do you think increased igf1 is a problem at an older age and longevity. damn, i want that elevated igf1 when im a senior citizen! lol. i dont know of correlations between igf1 and cancer.

B7emm
07-26-2009, 11:41 AM
Are there any studies that link a vegan diet to Alzheimer's? colagedele tn. has the highest concentration of vegan people in my area and something like 52% of the people develop Alzheimer's in there 60s.

RDFinders
07-26-2009, 11:57 AM
rdfinders, it is hard to discriminate causal relations with older patients since they usually have comorbidities including correlating osteoporosis, calcium deficiencies, etc.

though the literature is sketchy regarding renal failure and high protein, i dont need studies to tell me to be careful with high protein intake in older ages.

do you think as we age we have reduced renal functions? e.g., the suceptibiltiy of lower blood ph.
on dealing with the elderly - all organ system functions decline with advancing age. so pushing high any thing isn't good IMO with this group. but were we limiting it to just the elderly and high protein?

elderly and bone mass - hard to speculate causes of declining bone mass as it is multifactoral - less time outside (decreased vitamin D), decrease po intake (less calcium rich foods eaten), decreased absorption capacity, decreased HCl production to breakdown protein, decrease glut flora, limited mobility (so they lose lean body mass) and the list can go on.

in middle age adults - we don't know. none of us get bone scans when we reach 24 yoa, so we are not able to mark our bone densities and compare them over time.

TPT
07-26-2009, 12:10 PM
Are there any studies that link a vegan diet to Alzheimer's? colagedele tn. has the highest concentration of vegan people in my area and something like 52% of the people develop Alzheimer's in there 60s.


b7emm, yeah their is! well- sort of. open up a thread on this topic.

man, 52 percent is crazy!?

TPT
07-26-2009, 12:32 PM
on dealing with the elderly - all organ system functions decline with advancing age. so pushing high any thing isn't good IMO with this group. but were we limiting it to just the elderly and high protein?

elderly and bone mass - hard to speculate causes of declining bone mass as it is multifactoral - less time outside (decreased vitamin D), decrease po intake (less calcium rich foods eaten), decreased absorption capacity, decreased HCl production to breakdown protein, decrease glut flora, limited mobility (so they lose lean body mass) and the list can go on.

in middle age adults - we don't know. none of us get bone scans when we reach 24 yoa, so we are not able to mark our bone densities and compare them over time.


yes aging is sad. not to mention reduced test and hgh.

RDFinders
07-26-2009, 12:46 PM
yes aging is sad. not to mention reduced test and hgh.
or you can say - it sucks! but i think a big problem the elderly face is they get used to not doing anything. they really don't stay active mentally or physically, so it stands to reason - the use it or lose it principle is in full effect. key - keep working out to the upmost as you will fair better than your same aged counterparts.

B7emm
07-26-2009, 01:14 PM
thanks pt

Frosty
07-27-2009, 12:40 AM
do you think increased igf1 is a problem at an older age and longevity. damn, i want that elevated igf1 when im a senior citizen! lol. i dont know of correlations between igf1 and cancer.

IGF-1 can help to promote cancerous growths from what I've read. Although insulin is the main hormone to control for longevity AFAIK.

TPT
11-08-2009, 12:35 AM
bump for protein fanatics.

B7emm
11-08-2009, 12:40 AM
ah yes i remember, i know if i eat a lot of eggs my wife gets up set with me later that night. lol

natron
11-08-2009, 12:50 AM
any macronutrient has the ability to shorten life span, in the form of calories.

However, a high protein intake has way more positive influence on life expectancy than negative, and thats for sure.

I'll dig up some research tomorrow for debate

bigtimektz
11-09-2009, 10:42 PM
any macronutrient has the ability to shorten life span, in the form of calories.

However, a high protein intake has way more positive influence on life expectancy than negative, and thats for sure.

I'll dig up some research tomorrow for debate

Looking forward to it.

blacksterbmw
11-26-2009, 06:16 PM
Keep the body in an alkaline state by eating veg's or taking a supp like green lighting, its full of concentrate veg and stuff thats good for you

Frosty
11-26-2009, 07:55 PM
Keep the body in an alkaline state by eating veg's or taking a supp like green lighting, its full of concentrate veg and stuff thats good for you

Whey protein is going to help keep you less acidic as well vs. eating all solid food.

heavyiron
11-26-2009, 11:08 PM
I lift weights so no worries about bone loss. Maybe you guys should try it.

Frosty
11-26-2009, 11:48 PM
Interesting Dr. Scott Connelly talked about hunter gathers having higher bone density than agricultural folk in a recent Super Human Radio show.

freak
11-27-2009, 03:25 PM
Keep the body in an alkaline state by eating veg's or taking a supp like green lighting, its full of concentrate veg and stuff thats good for you
i was under the impression that our bodies regulate pH....

Frosty
11-28-2009, 01:10 AM
i was under the impression that our bodies regulate pH....

They do but why not make it easier on the body so it doesn't have to do something like pull minerals from body stores to regulate when eating a very acidic diet.

freak
11-28-2009, 02:38 AM
They do but why not make it easier on the body so it doesn't have to do something like pull minerals from body stores to regulate when eating a very acidic diet.
but when you eat these "basic" foods, they enter the stomach where it begins to be broken down by stomach acid... which is very acidic... these foods then enter the small intestine at an acidic pH... i'm pretty confident that our bodies regulate pH pretty effectively.

Frosty
11-28-2009, 02:42 AM
but when you eat these "basic" foods, they enter the stomach where it begins to be broken down by stomach acid... which is very acidic... these foods then enter the small intestine at an acidic pH... i'm pretty confident that our bodies regulate pH pretty effectively.

But that has nothing to do with the net effect on the body. Lemon juice is acidic but has an alkalinizing effect, for example.

AVBG
11-28-2009, 03:38 AM
Interesting read(s).thanks

freak
11-28-2009, 12:05 PM
But that has nothing to do with the net effect on the body. Lemon juice is acidic but has an alkalinizing effect, for example.
how? can you give any references i can read??

freak
11-28-2009, 04:05 PM
But that has nothing to do with the net effect on the body. Lemon juice is acidic but has an alkalinizing effect, for example.
this has to do with the "alkaline water" bullshit but, i think it may apply here as well.

"Don't be taken in by the pseudoscience peddled by quacks, cranks, kooks or crooks! (sample (http://mysite.verizon.net/felipe2/id18.html)) Instead, take a look at these references provided by real scientists for the education of medical students:


Blood, Sweat and Buffers (http://www.chemistry.wustl.edu/%7Eedudev/LabTutorials/Buffer/Buffer.html) a course tutorial site from Washington University.
Acid-base tutorial (http://www.acid-base.com/index.php) - by Prof. Alan Grogono of Tulane University medical school
Urine pH (http://rnceus.com/ua/uaph.html) varies to help maintain acid-base balance
Acid-base disorders (http://books.google.com/books?id=sPgGqotdzqAC&pg=PA78&lpg=PA78&dq=nephrology+ph&source=bl&ots=djCjTPakdy&sig=SsUwMdO2FWzZ3t_jOHrOlY7CE7k&hl=en&ei=q0zXSrfOKY7-tQOF9ZjHAg&sa=X&oi=book_result&ct=result&resnum=17&ved=0CEUQ6AEwEDgU#v=onepage&q=nephrology%20ph&f=false)

...and any claims that "acidity" promotes cancer is deceptive nonsense."


http://www.chem1.com/CQ/ionbunk.html

natron
11-28-2009, 04:52 PM
but when you eat these "basic" foods, they enter the stomach where it begins to be broken down by stomach acid... which is very acidic... these foods then enter the small intestine at an acidic pH... i'm pretty confident that our bodies regulate pH pretty effectively.

When your organs function properly, yes

freak
11-28-2009, 04:56 PM
When your organs function properly, yes
what is your opinion on these "alkaline diets" and "alkaline water" ideas?

natron
11-28-2009, 05:19 PM
what is your opinion on these "alkaline diets" and "alkaline water" ideas?

I wouldn't doubt that for certain individual with certain conditions, they may be applicable to some degree.

Now with that said, this type of science does not give me a chubby at all, and it is nothing I would ever personally do.

That's about it.

freak
11-28-2009, 10:03 PM
I wouldn't doubt that for certain individual with certain conditions, they may be applicable to some degree.

Now with that said, this type of science does not give me a chubby at all, and it is nothing I would ever personally do.

That's about it.
from reading some of your posts you sound like a smart guy. what education do you have? what do you do for a career??

natron
11-28-2009, 10:19 PM
from reading some of your posts you sound like a smart guy. what education do you have? what do you do for a career??

Safety Consultant in the oil/gas industry. By trade I'm a registered nutritional consultant practitioner

freak
11-28-2009, 11:22 PM
Safety Consultant in the oil/gas industry. By trade I'm a registered nutritional consultant practitioner
wtf is that and who is the regulatory body? is it recognized by the ADA?

natron
11-29-2009, 12:45 AM
wtf is that and who is the regulatory body? is it recognized by the ADA?


It's Canadian, thus equal to nothing.

But since your asking, it's like being a nutritionist, while being a step or two below a homeopathic doctor. Not quite academically, but acclicable experience wise.

I studied in B.C., through The Longevity Center of Natural Health.

I graduated with a beer in my hand.

I have also worked in the Health Food Industry for 4-5 years, but honestly, ,my experience mostly comes in the form of curiosity, willingness to help others and my own personal gain.

natron
11-29-2009, 12:59 AM
Just kidding, I hold a gas pump for a living, couldn't quite make it to the edit function fast enough???

lol

freak
11-29-2009, 01:44 AM
It's Canadian, thus equal to nothing.

But since your asking, it's like being a nutritionist, while being a step or two below a homeopathic doctor. Not quite academically, but acclicable experience wise.

I studied in B.C., through The Longevity Center of Natural Health.

I graduated with a beer in my hand.

I have also worked in the Health Food Industry for 4-5 years, but honestly, ,my experience mostly comes in the form of curiosity, willingness to help others and my own personal gain.
im in a nutrition and dietetics program at a canadian university right now... and it is something. were you able to apply for an internship? how long was the program?

Curt James
11-29-2009, 02:09 AM
I can't find the title I'm looking for but I do own a book (SOMEWHERE in my apartment) that spells out the authors' (a son and daughter, I believe) recommendations on eating less to lengthen life and increase health.

Did find this bit on calorie-restriction that may be applicable to this discussion:

The History of the Restricted Calorie Diet
The medical community began taking notice of the restricted calorie diet when the diet was tested on animals. The scientific testing focused on insects and other animals with a tendency for short lives. While the results were not entirely clear, researchers found that animals on restricted calorie diets did live longer than animals of the same species on normal diets. In addition to showing signs of living longer, animals who were on restricted calorie diets were less likely to develop diseases that are more common in older age, such as diabetes and heart disease.

Because long-term testing with animals with a longer life span could take decades, only limited research has been with animals who tend to live more than a few years. Though results in monkeys has shown to be promising, the results are only preliminary in nature.

Read more: http://diet-trends.suite101.com/article.cfm/the_calorie_restriction_diet

natron
11-29-2009, 01:15 PM
I can't find the title I'm looking for but I do own a book (SOMEWHERE in my apartment) that spells out the authors' (a son and daughter, I believe) recommendations on eating less to lengthen life and increase health.

Did find this bit on calorie-restriction that may be applicable to this discussion:

The History of the Restricted Calorie Diet
The medical community began taking notice of the restricted calorie diet when the diet was tested on animals. The scientific testing focused on insects and other animals with a tendency for short lives. While the results were not entirely clear, researchers found that animals on restricted calorie diets did live longer than animals of the same species on normal diets. In addition to showing signs of living longer, animals who were on restricted calorie diets were less likely to develop diseases that are more common in older age, such as diabetes and heart disease.

Because long-term testing with animals with a longer life span could take decades, only limited research has been with animals who tend to live more than a few years. Though results in monkeys has shown to be promising, the results are only preliminary in nature.

Read more: http://diet-trends.suite101.com/article.cfm/the_calorie_restriction_diet

This is sort of along the lines of red wine extract and it's effect on increased longevity via calorie mimetics.