High protein diet brings risk of kidney stones
BMJ 2002; 325 doi: https://doi.org/10.1136/bmj.325.7361.408/d (Published 24 August 2002) Cite this as: BMJ 2002;325:408
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From the ages of 25-42, I had painful kidney stone attacks every 2
years on average. Doctors could not determine why, as I had none of the
traditional risk factors. When I adopted a low-carbohydrate, high-fat in
2005 (6 years ago), I stopped having the attacks. I also lost 30 lbs in 3
months (and kept it off), dramatically improved my lipid profile, boosted
my energy levels and ramped up my immune function. Sadly, the unfounded
fear of fat prevents professionals from acknowledging the benefits of a
low-carb, MODERATE-protein, high-fat diet.
Competing interests: No competing interests
Cutting back on sugar, starch, and fat in favor of fruits,
vegetables, lean meats and plenty of fluids, combined with regular
exercise and rest seems to provide plenty of nutrition, fiber and
vitamins, without increasing risks
associated with fad diets. Forget about the "hot buttons" like Adkins or
Ornish. This doesn't have to be overly complicated.
Competing interests: No competing interests
Respondents to recent publications on this topic treat the issues
involved in dreadfully narrow ways. It seems that they are either heavily
promoting an extreme view of nutritional excellence (eg high fat for
life), believe that national nutritional guidelines suit every individual
or come from some extraordinarily confined branch of medical practise.
None, it seems is interested in the mechanisms which may explain why short
-term dietary modification could have longer term benefits.
Put simply, depriving the tissues of readily available carbohydrates
induces a requirement that glucogenesis supply the shortfall. Since
roughly half of the amino acids in protein are glucogenic, they become the
preferred energy source, fat being unattractive because only the glycerol
portion is glucogenic. Since glucose per se is needed by so many tissues
energy, in the form of ATP, is needed so that glucose can be synthesised
from the deaminated amino acids. Ultimately, fatty acids must be oxidised
to supply the ATP. Other energy needs such as those involved in excreting
an unusually large amount of urea and in the handling of the metabolic
products of those amino acids which are ketogenic further increase the
need for extra ATP and fatty acid oxidation.
The end result of this scenario seems to predispose to fat loss.
Certainly, if it were proposed that extreme dieary habits become a
lifelong change, reservations would be entirely justified. If however it
were seen as an acute remedy for a condition caused by long-term dietary
abuse, then biochemical logic suggests a place for a high protein-low
carbohydrate regime.
Competing interests: No competing interests
A search of recent literature does not show excess of kidney stones
among the Inuit whose diet is based on protein; there appears, however, to
be a high risk of renal cancer among Inuit women apparently consuming
Western diet.
Competing interests: No competing interests
Grains, beans, potatoes, the milk of other species, and refined
sugars are not edible to any species of Primate without technological
intervention(1.). Without these "Fruits of the Tree of Knowledge" humans
must eat a low-carb diet to survive.
Most Primates eat a low-carb diet for a substantial portion of every
year when high-carb fruits are not in season and are in heavy ketosis
during this time(2).
Those humans who eat a very low-fat diet (Sumo wrestlers) have the
highest rates of heart disease and stroke (3). Those having the highest
animal fat intake have the lowest rates of these disorders (4). Eating a
low-fat diet has been shown to increase LDL cholesterol and triglycerides
in overweight patients faster than any other method known to science (5).
The low-fat craze has been exposed as a hoax (6). Turns out that low
-fat and vegetarian diets benefit only food manufactures due to their
intrinsically high profit margins.
A natural high-fat, high calorie, low-carb diet is what humans were
evolved to eat and has shown benefits for most auto-immune disorders as
well as obesity.(see complete bibliography at NeanderThin.com .
1. Stahl, Ann Brower,
"Hominid Dietary Selection Before Fire."
Current Anthropology Vol. 25, No. 2 (April 1984) 151-68.
2. Knott,C.
"Changes in orangutan diet, caloric intake and ketones in response to
fluctuating fruit availability".
Int J Primatol 19: 1061-1079.
3. Roach, Mary,
"Advice from the World's Biggest Weight Experts: Their Gain Can Be Your
Loss." Health (March/April 1993)
62-72.
4. Shaper, A. G. et al,
"Cardiovascular studies in the Samburu tribe of Northern Kenya."
American Heart Journal Vol. 63 No. 4 (April 1962) 437-442
5.Garg, Abhimanyu, M.B.B.S., M.D. et al,
"Effects of Varying Carbohydrate Content of Diet in Patients with Non-
Insulin-Dependent Diabetes Mellitus."
Journal of the AmericanMedicalAssociation vol. 271, #18 (May 11, 1994)
1421-1428.
6. Taub, Gary
"What If It's All a Big Fat Lie"
New York Times
July 7, 2002
(see also his excelent article in Science "The Soft Science of Dietary
Fat") March, 2002
Ray Audette
Author "NeanderThin: Eat like a Caveman to Achieve a Lean, Strong, Healthy
Body" (St. Martin's Press)
Competing interests: No competing interests
Regarding the debate concerning dietary protein and renal stones it
is worth emphasising that it is
animal protein that leads to increased fixed acid concentrations (acid
ash). This acid load has the effect of increasing urinary calcium
excretion (1), reduces urinary citrate (2) and decreases urinary pH which
increases the amount of unassociated uric acid. These effects will
increase the likelihood of calcium crystal formation in the collecting
duct, the point of maximal urinary concentration, with uric acid crystals
often acting as nuclei for further crystal formation (3). In this
environment, increased water intake becomes crucial to maintaining calcium
in solution.
Compared to animal protein, vegetable protein has a reduced effect on
urinary calcium, uric acid and citrate secondary to generation of less
fixed acid. If the Robert Atkins diet in principle relies on high protein
intake achieved by increased animal protein intake then this will lead to
an increased risk of renal stone formation over time.
References
(1) Breslau NA, Brinkley L, Hill KD, Pak CY. Relationship of animal
protein-rich diet to kidney stone formation and calcium metabolism. J Clin
Endorinol Metab 1988; 66:140-6.
(2) Kok DJ, Iestra JA, Doorenbos CJ, Papapoulos SE. The effects of
dietary excesses in animal protein and in sodium on the composition and
the crystallization kinetics of calcium oxalate monohydrate in urines of
healthy men. J Clin Endocrinol Metab. 1990; 71:861-7.
(3) Sayer JA, Simmons NL.Urinary Stone Formation: Dent's Disease
Moves Understanding Forward. Exp Nephrol 2002; 10: 176-81
Competing interests: No competing interests
High protein, low carbohydrate diets are definately unhealthy for
several reasons.
First, one only needs to compare any of these diets to
Canada's Food Guide to realize that dietary fibre is lacking. This could
in theory increase the risk of constipation, diverticulosis and colonic
neoplasia.
Second, these diets are relatively high in fat - this could
increase the risk of coronary artery disease, peripheral vascular disease
and prostate cancer.
Third, such diets typically view foods as falling
into one or more of three groups - protein, fat and carbohydrate. No
regard is given for nutritional value. When compared to the Canadian Fod
Guide for Healthy Eating, it becomes apparent that deficiencies would
exist in essential vitamins and minerals such as calcium.
Fourth, the
notion that one can facilitate weight loss by combining protein, fats and
carbohydrate in some magical and 'balanced' way is ridiculous. These
diets do cause weight loss, but not for the reasons claimed.
Weight loss
only occurs because fewer calories are consumed overall. Clearly, if one
restricts carbohydrate intake (desserts, fruit, pastas, breads etc.) the
net caloric intake also decreases significantly. Fifth, these are diets
rather than true changes in eating habits. This leads to a yo-yo effect
with respect to body weight. In summary, for the reasons outlined above I
NEVER recommend these diets to my patients. What we all need to do is eat
LESS, follow Canada's Food Guide (or other well balanced diet), EXERCISE
more and stop looking for quick fixes!
Competing interests: No competing interests
The claim that protein intake leads to kidney stones is a popular
myth that is not supported by the facts. Although protein restricted diets
are helpful for people who already have kidney disease, eating meat does
not cause kidney problems.(1) Indeed, the fat-soluble vitamins and
saturated fatty acids found in animal foods are essential for properly
functioning kidneys.(2)
That protein intake adversely affects bone strength is another
popular myth. When studies were done with people eating meat with its fat,
no calcium loss was detected, even over a long period of time.(3) Other
studies confirmed that meat eating did not adversely affect calcium
balance (4) and that protein actually promotes stronger bones.(5)
But current low-carb diets should not be thought of as high-protein.
They are normal-protein, with carbs replaced by fats for energy, they are
- or should be - high fat.
Barry Groves, PhD
Independent research
Author of Eat Fat, Get Thin!
References
1. Dwyer JT, Madans JH, Turnbull B, Cornoni-Huntley J, Dresser C, Everett
DF, Perrone RD. Diet, indicators of kidney disease, and late mortality
among older persons in the NHANES I Epidemiologic Follow-up Study. Amer J
of Pub Health, 1994, 84:(8): 1299-1303.
2. Enig M. Saturated fats and the kidneys. Wise Traditions, 2000, 1:3:49.
Posted at http://www.westonaprice.org.
3. Spencer H, Kramer L. Factors contributing to osteoporosis. J Nutr,
1986, 116:316-319; Further studies of the effect of a high protein diet as
meat on calcium metabolism. Amer J Clin Nutr., 1983, 37:6: 924-9.
4. Hunt JR, Gallagher SK, Johnson LK, Lykken GI. High- versus low-meat
diets: Effects on zinc absorption, iron status, and calcium, copper, iron,
magnesium, manganese, nitrogen, phosphorus, and zinc balance in
postmenopausal women. Amer J Clin Nutr, 1995, 62:621-32; Spencer H, Kramer
L, Osis D.. Do protein and phosphorus cause calcium loss? J Nutr
1988;118:657-60.
5. Cooper C, Atkinson EJ, Hensrud DD, Wahner HW, O'Fallon WM, Riggs BL,
Melton LJ 3rd.. Dietary protein and bone mass in women. Calcif Tiss. Int.,
1996, 58:320-5.
Competing interests: No competing interests
Re: High protein diet brings risk of kidney stones
Renal stone is one of the diseases that are discussed by Avicenna in "Canon of medicine" about 10 centuries ago.
Avicenna, a Persian physician, was one of the most outstanding medical scientists and practitioners ever. His most famous medical book is “The Canon of medicine” that was one of the main medical references in the western countries until the 16th century (1).
He has explained pathophysiology of renal stones at first and then enumerated factors that cause stone formation. He believed that nutritional habits are important factor in this process. He restricted some foods such as milk, cheese, some types of fishes and camel, cow and goat meat for patients with renal stone (2).
He has written in his book that gastric dysfunction and immediate post eating exercise are other risk factors for stone formation. Therefore, he believed that treatment of digestive disorders is essential in renal stone management course (3).
Avicenna has written on the differential characteristics of kidney and bladder stones: “renal stones are small, soft and reddish but bladder stones are big, hard with white and gray color. Bladder stones are more prevalent in children and thin people unlike renal stones that are common in obese and old people (4).
Avicenna’s description of renal stone symptoms has many similarities to modern medicine ones.
Urine examination has been done by Avicenna as a diagnostic test in determination of stone type. Urine volume, viscosity, color and its sediment was important aspects in his macroscopic evaluation (5).
Finally he has suggested his medical plan for stones treatment that can be a new idea for researchers to be investigated.
References
1- Zargaran A., Mehdizadeh A., Zarshenas MM. Mohagheghzadeh A. Avicenna (980–1037 AD). J Neurol. 2012 Feb; 259(2):389-90.
2, 3- Avicenna,The Canon of medicine (Persian translation), 3rd edition. Tehran: Ministry of Health and Medical Education of Iran, Com
4- Jocham, D. "Historical development of ESWL." Principles of Extracorporeal Shock Wave Lithotripsy, Churchill Livingstone, New York (1987): 1-11.
5- YURDAKÔK, MURAT. "URINE ANALYSIS ACCORDING TO AVICENNA." Acts of the International Symposium on Ibn Turk, Khwârezmî, Fârâbî, Beyrûnî and Ibn Sînâ:(Ankara, 9-12 September 1985). Vol. 41. Atatürk Culture Center, 1990.
Competing interests: No competing interests