T Nation

Excess Protein Dangerous?


I was looking through this weeks askmen.com articles and found an article called "Top 10 Dangerous Bodybuilding Habits".

The following paragraph is from number 6:

"Eating too much protein

Why it's dangerous: In the off-season, bodybuilders typically eat 1.25 to 1.5 grams of protein per pound of body weight each day. Before competitions, many increase their protein intake to 1.75 to 2.0 g per pound. However, eating too much protein can have many negative effects. First, it may lead to higher levels of homocysteine, a by-product of protein metabolism and an independent risk factor for heart disease. Moreover, having too much protein in your body can cause irreversible kidney damage and increase your risk of osteoporosis.

What to do instead:

Nutritionists generally say that no one, not even bodybuilders, should consume more than 1.7 g of protein per pound of body weight a day. Keep in mind that this is the upper limit if you're training hard ; if you're training only slightly or moderately, your protein intake should be closer to 0.8 to 1.0 gram per pound."

What are your takes on this?

Personally my protein intake is around 1.5 gram per pound at the moment.


Read this

High-protein diets: potential effects on the kidney in renal health and disease.

Friedman AN.

Division of Nephrology, Indiana University School of Medicine, Indianapolis, IN 46202, USA. allfried@iupui.edu

High-protein (HP) weight-loss diets have existed in the United States for decades, although their popularity has recently surged as obesity has become more common. Despite their widespread use, valid concerns exist that HP diets may induce clinically important alterations in renal function and health. HP consumption has been found, under various conditions, to lead to glomerular hyperfiltration and hyperemia; acceleration of chronic kidney disease (CKD); increased proteinuria; diuresis, natriuresis, and kaliuresis with associated blood pressure changes; increased risk for nephrolithiasis; and various metabolic alterations. Unfortunately, a comprehensive understanding of the implications of HP diets is limited by the lack of a universally accepted definition for HP intake, a paucity of rigorous long-term human interventional studies that necessitate relying on short-term or fairly circumstantial evidence, and sparse data on the effects of HP consumption in obese individuals. In addition, matters are further complicated because the renal impact HP diets for limited periods is most likely different than that for more chronic consumption. Nevertheless, although there are no clear renal-related contraindications to HP diets in individuals with healthy kidney function, the theoretical risks should be reviewed carefully with the patient. In contrast, HP diets have the potential for significant harm in individuals with CKD and should be avoided if possible. Because CKD is often a silent disease, all individuals should undergo a screening serum creatinine measurement and urinary dipstick test for proteinuria before the initiation of such a diet.


"there are no clear renal-related contraindications to HP diets in individuals with healthy kidney function"

So your kidneys won't explode.


Nutrition and Health Programme, Wageningen Centre for Food Sciences, Wageningen, The Netherlands. petra.verhoef@wur.nl

BACKGROUND: A high plasma concentration of total homocysteine (tHcy) is associated with increased risk of cardiovascular disease. A high protein intake and hence a high intake of methionine--the sole dietary precursor of homocysteine--may raise plasma tHcy concentrations. OBJECTIVES: We studied whether high intake of protein increases plasma concentrations of tHcy in the fasting state and throughout the day. DESIGN: We conducted a randomized, dietary controlled, crossover trial in 20 healthy men aged 18-44 y. For 8 d, men consumed a controlled low-protein diet enriched with either a protein supplement [high-protein diet (21% of energy as protein)] or an isocaloric amount of short-chain glucose polymers [low-protein diet (9% of energy as protein)]. After a 13-d washout period, treatments were reversed. On days 1 and 8 of each treatment period, blood was sampled before breakfast (fasting) and throughout the day. RESULTS: Fasting tHcy concentrations did not differ significantly after the 1-wk high-protein and the 1-wk low-protein diets. The high-protein diet resulted in a significantly higher area under the 24-h homocysteine-by-time curves compared with the low-protein diet, both on day 1 (difference: 45.1 h x micromol/L; 95% CI: 35.3, 54.8 h x micromol/L; P < 0.0001) and on day 8 (difference: 24.7 h x micromol/L; 95% CI: 15.0, 34.5 h x micromol/L; P < 0.0001). CONCLUSIONS: A high-protein diet increases tHcy concentrations throughout the day but does not increase fasting tHcy concentrations. As previously shown, the extent of the tHcy increase is modified by the amino acid composition of the protein diet. The clinical relevance of this finding depends on whether high concentrations of tHcy-particularly postprandially-cause cardiovascular disease.

There is no proof that a high protein diet is associated with high plasma concentration of total homocysteine (tHcy), which is associated with increased risk of cardiovascular disease.


Protein and amino acids for athletes.

Tipton KD, Wolfe RR.

Department of Surgery, University of Texas Medical Branch, Shriner's Hospital for Children, 815 Market Street, Galveston, TX 77550, USA. ktipton@utmb.edu

The main determinants of an athlete's protein needs are their training regime and habitual nutrient intake. Most athletes ingest sufficient protein in their habitual diet. Additional protein will confer only a minimal, albeit arguably important, additional advantage. Given sufficient energy intake, lean body mass can be maintained within a wide range of protein intakes. Since there is limited evidence for harmful effects of a high protein intake and there is a metabolic rationale for the efficacy of an increase in protein, if muscle hypertrophy is the goal, a higher protein intake within the context of an athlete's overall dietary requirements may be beneficial. However, there are few convincing outcome data to indicate that the ingestion of a high amount of protein (2-3 g x kg(-1) BW x day(-1), where BW = body weight) is necessary. Current literature suggests that it may be too simplistic to rely on recommendations of a particular amount of protein per day. Acute studies suggest that for any given amount of protein, the metabolic response is dependent on other factors, including the timing of ingestion in relation to exercise and/or other nutrients, the composition of ingested amino acids and the type of protein.

There is indeed, no need for a very high protein consumption, there is no harm in that either.


I am sure this was probably covered in another protein/nutrition thread-

So are we to assume that the "warnings" about protein through articles are based on just consuming any protein no matter what type or preparation? Also, are we to ceom to the conclusion that even increasing (or regular) consumption of vegetables, fruits, and whole grains would do nothing?

Articles, or maybe some science journals, sometimes appear to have a cool way to be either to the point or half-assed. Not really judging the article or the info, but just coming up with more questions...

question the answers


Oh my gosh! Soon they'll be saying vitamin E is evil, lol.


AH just finished reading the whole article.

I dunno what to say other than while there may be a very small portion of T-Nation confirmed truth covered in this askmen article (which appears to be written or answered by a woman, no offense just the irony of it), it's chock full of fitness myths.

Everything from stretching, "dangerous" stimulants that have been well documented in the mainstream media, and steroid use.

I read it for the entertainment, it's good for this article to be brought up here...it's like the article version of the 'Squat-Rack Curls' thread. However it should have been entitled not about bodybuilding, but 10 Dangerous GymRat Habits.


Thanks for those, are you getting them from Pub-med?


The nutritionist at the gym I used to PT for always maintained that as long as you were being properly hydrated, you wouldn't have significant problems. Properly hydrated is relative, but presuming you drink a lot of water throughout the day, then you should be fine.




is a great starting point to look up actual scientific studies. So when some supplement companies claim their product X feels like deca, use the search function and review the existing data.


Fahd: Thank you very much for taking the time to find and post those articles. A serious approach like that is very appreciated.


No problem bro.


askmen.com is about as reliable a source of information as a magic 8 ball...


My cousin just got diagnosed with IGA nephropathy, he's 19. This is where IGa (Immuno-globin a) gets clogged up in the gloerulei (sp?) and causes higher blood pressure and blood and urea to be peed out. Casuing blood in the urine. He is 19 and on BP medication, and his BP was 160/120 at one point and this guy is a seriously gifted athlete, i'm very close with him and I joke that his high blood pressure keeps his limbs supplied with energy. Anyways, he is 5'10" and 180lbs and restricted to 80 grams of protein a day, he is an avid weight lifter and used to eat really big, now he is restricted. His Nephrology doctor told him that it's fine for the kidneys to have high protein in the kidneys and that they adapt, however with pre-exisiting renal disease the clogged filter in the kidney just get more backed up. So it's fine guys. You're lucky you don't have renal disease, he will either be on dialysis in 10-15 years or need a kidney transplant, he's lucky myself, my brother, and his brother are donors for him if he needs, it. I just tell him he better not drink my kidney to death if I do.


Remember that basically all evidence of high protein diets not being negative towards kidney function are based on what people here would classify as low protein diets.

There is well and truely next to no real evidence for intakes much over 1g/lb, and those htat looked at figures around that are usually short term. 1.5-2.0g for a long time period is a load of guess work for kidney function.

We know it does increase glomerular filtration, and there is potential over a long period to cause negative effects in certain segemnts of the population (do you know your current kidney function?) so its basically just learn as we go.


Certain segments of the population...like those with kidney disease? There is NO evidence that shows healthy individuals are at risk by eating high protein. NONE. Therefore, how could it have the "potential" to cause negative effects? Why assign a "possible negative" to it at all? What if low protein diets are "potentially dangerous"? What if moderate protein diets are "potentially dangerous"? You sound like one of those who looks at any guy who lifts weights and tries their hardest to find the most negative aspect to focus on to point out the activity as a negative. Why wouldn't you just as easily write, "high protein diets are potentially very healthy for the body"?


Exactly that was his point. What do you disagree with him about?


Wow, i see your bias showing there, you better cover it before you trip on it.

How many people know their kidney function?

As has been said (by you as well I think) in another thread, how many people know something as simple as their BP? (a risk factor for kidney disease).

With current data showing ~11% of the adult population of the united states has some form of KD, who here knows if they have or not?

One in ten.

There are a whole lot more people who have no idea about their kidney function, than who actually do know.

Just as there is NO evidence that eating high protein is safe (high protiein from research setting is ~2g/kg, or 0.9g/lb, nowhere near the commonly recommended 1.5 - 2.0grams per lb)

Yep, none

THere is potential for positive effects, did I say otherwise? Just becuase I said there was potential for negatives does not mean there are no positives.

There is no research looking at the range of protein intakes routinely recommended here. Saying they are healthy with no evidence base to substantiate the claim is what?

Why assign healthy? to it at all, especially as there is no evidence at the protein ranges we are discussing?

THey are not potentially dangerous.

They ARE dangerous

Seeing as the bulk of the evidence that we have is based around moderate intakes, with the available evidence they are 'safe' for the general population

Thats nice, you just sound like a normal bodybuilder.

If 1gram of X is ok, 5g of X will create awsomeness.

Becuase that has already been said within this thread.

So I provided a counterpoint.


To kinda support Aaron's claim, on the first study I posted:

"In contrast, HP diets have the potential for significant harm in individuals with CKD and should be avoided if possible. Because CKD is often a silent disease, all individuals should undergo a screening serum creatinine measurement and urinary dipstick test for proteinuria before the initiation of such a diet. "

So maybe the take home message is to check your kidney function before going on a high protein diet?