Sachayko nie czytałem artykułu do którego dałeś linka. Wokół monohydratu powstało wiele marketingowych mitów.
Są pewne pojedyncze raporty, mimo pewnych prób nie mamy gwarancji jaki wpływ będzie przy `naprawdę długo trwającej` suplementacji, ale według badań u zdrowych osób przy właściwej suplementacji nie ma przekonywujących dowodów, że istniej problem odnośnie nerek:
Effects of creatine use on the athlete's kidney.
Farquhar WB, Zambraski EJ.
HRCA Research and Training Institute, Harvard Division on Aging, 1200 Centre Street, Boston, MA 02131, USA. [email protected]
With regard to athletes attempting to improve their performance, at the present time creatine monohydrate is clearly the most widely used dietary supplement or ergogenic aid. Loading doses as high as 20 g/d are typical among athletes. The majority (> 90%) of the creatine ingested is removed from the plasma by the kidney and excreted in the urine. Despite relatively few isolated reports of renal dysfunction in persons taking creatine, the studies completed to date suggest that in normal healthy individuals the kidneys are able to excrete creatine, and its end product creatinine, in a manner that does not adversely alter renal function. This situation would be predicted to be different in persons with impaired glomerular filtration or inherent renal disease. The question of whether long-term creatine supplementation (ie, months to years) has any deleterious affects on renal structure or function can not be answered at this time. The limited number of studies that have addressed the issue of the chronic use of creatine have not seen remarkable changes in renal function. However, physicians should be aware that the safety of long-term creatine supplementation, in regard to the effects on the kidneys, cannot be guaranteed. More information is needed on possible changes in blood pressure, protein/albumin excretion, and glomerular filtration in athletes who are habitual users of this compound.
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Adverse effects of creatine supplementation: fact or fiction?
Poortmans JR, Francaux M.
Physiological Chemistry, Higher Institute of Physical Education and Readaptation, Free University of Brussels, Bruxelles, Belgium. [email protected]
The consumption of oral creatine monohydrate has become increasingly common among professional and amateur athletes. Despite numerous publications on the ergogenic effects of this naturally occurring substance, there is little information on the possible adverse effects of this supplement. The objectives of this review are to identify the scientific facts and contrast them with reports in the news media, which have repeatedly emphasised the health risks of creatine supplementation and do not hesitate to draw broad conclusions from individual case reports. Exogenous creatine supplements are often consumed by athletes in amounts of up to 20 g/day for a few days, followed by 1 to 10 g/day for weeks, months and even years. Usually, consumers do not report any adverse effects, but body mass increases. There are few reports that creatine supplementation has protective effects in heart, muscle and neurological diseases. Gastrointestinal disturbances and muscle cramps have been reported occasionally in healthy individuals, but the effects are anecdotal. Liver and kidney dysfunction have also been suggested on the basis of small changes in markers of organ function and of occasional case reports, but well controlled studies on the adverse effects of exogenous creatine supplementation are almost nonexistent. We have investigated liver changes during medium term (4 weeks) creatine supplementation in young athletes. None showed any evidence of dysfunction on the basis of serum enzymes and urea production.
Short term (5 days), medium term (9 weeks) and long term (up to 5 years) oral creatine supplementation has been studied in small cohorts of athletes whose kidney function was monitored by clearance methods and urine protein excretion rate. We did not find any adverse effects on renal function. The present review is not intended to reach conclusions on the effect of creatine supplementation on sport performance, but we believe that there is no evidence for deleterious effects in healthy individuals. Nevertheless, idiosyncratic effects may occur when large amounts of an exogenous substance containing an amino group are consumed, with the consequent increased load on the liver and kidneys. Regular monitoring is compulsory to avoid any abnormal reactions during oral creatine supplementation.
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Long-term oral creatine supplementation does not impair renal function in healthy athletes.
Poortmans JR, Francaux M.
Chimie Physiologique, Institut Superieur d'Education Physique et de Kinesitherapie, Universite Libre de Bruxelles, Brussels, Belgium. [email protected]
PURPOSE: Oral creatine supplementation is widely used in sportsmen and women. Side effects have been postulated, but no thorough investigations have been conducted to support these assertions. It is important to know whether long-term oral creatine supplementation has any detrimental effects on kidney function in healthy population. METHODS: Creatinine, urea, and plasma albumin clearances have been determined in oral creatine consumers (10 months to 5 yr) and in a control group. RESULTS: There were no statistical differences between the control group and the creatine consumer group for plasma contents and urine excretion rates for creatinine, urea, and albumin. Clearance of these compounds did not differ between the two groups. Thus, glomerular filtration rate, tubular reabsorption, and glomerular membrane permeability were normal in both groups.
CONCLUSIONS: Neither short-term, medium-term, nor long-term oral creatine supplements induce detrimental effects on the kidney of healthy individuals.
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Zmieniony przez - ellis w dniu 2006-10-19 15:57:58