Kreatin och leverskador

[hpb]

Finns det några studier som pekar för / mot?

Vet att grub skrev att det inte finns några under 2005 men fick idag höra att en träningskamrat hade blivit rekomenderad att göra upphåll då och då med kreatinet av sin läkare för att kroppen blir van och inte tar upp det ur maten.
Nya rön eller nytt bs?

[King Grub]

Det finns inga vetenskapliga studier som styrker ett antagande att kreatin skall vara skadlig för vare sig friska njurar eller en frisk lever. Det saknas långtidsstudier som sträcker sig längre än ett år på högt intag, men det finns i dag inga skäl att misstänka någon sådan skadeverkning.

[hpb]

Det finns inga vetenskapliga studier som styrker ett antagande att kreatin skall vara skadlig för vare sig friska njurar eller en frisk lever. Det saknas långtidsstudier på högt intag, men det finns i dag inga skäl att misstänka någon sådan skadeverkning.

Finns det några studier som styrker att det är ofarligt?

[Snakeyes]

Long-term creatine supplementation does not significantly affect clinical markers of health in athletes.

Kreider RB, Melton C, Rasmussen CJ, Greenwood M, Lancaster S, Cantler EC, Milnor P, Almada AL.

Exercise and Sport Nutrition Laboratory, Department of Human Movement Sciences and Education, The University of Memphis, Memphis, TN, USA. Richard_Kreider@baylor.edu

Creatine has been reported to be an effective ergogenic aid for athletes. However, concerns have been raised regarding the long-term safety of creatine supplementation. This study examined the effects of long-term creatine supplementation on a 69-item panel of serum, whole blood, and urinary markers of clinical health status in athletes. Over a 21-month period, 98 Division IA college football players were administered in an open label manner creatine or non-creatine containing supplements following training sessions. Subjects who ingested creatine were administered 15.75 g/day of creatine monohydrate for 5 days and an average of 5 g/day thereafter in 5-10 g/day doses. Fasting blood and 24-h urine samples were collected at 0, 1, 1.5, 4, 6, 10, 12, 17, and 21 months of training. A comprehensive quantitative clinical chemistry panel was determined on serum and whole blood samples (metabolic markers, muscle and liver enzymes, electrolytes, lipid profiles, hematological markers, and lymphocytes). In addition, urine samples were quantitatively and qualitative analyzed to assess clinical status and renal function. At the end of the study, subjects were categorized into groups that did not take creatine (n = 44) and subjects who took creatine for 0-6 months (mean 4.4 +/- 1.8 months, n = 12), 7-12 months (mean 9.3 +/- 2.0 months, n = 25), and 12-21 months (mean 19.3 +/- 2.4 months, n = 17). Baseline and the subjects' final blood and urine samples were analyzed by MANOVA and 2 x 2 repeated measures ANOVA univariate tests. MANOVA revealed no significant differences (p = 0.51) among groups in the 54-item panel of quantitative blood and urine markers assessed. Univariate analysis revealed no clinically significant interactions among groups in markers of clinical status. In addition, no apparent differences were observed among groups in the 15-item panel of qualitative urine markers. Results indicate that long-term creatine supplementation (up to 21-months) does not appear to adversely effect markers of health status in athletes undergoing intense training in comparison to athletes who do not take creatine.

PMID: 12701816 [PubMed - indexed for MEDLINE]

[King Grub]

Int J Sports Med. 2005 May;26(4):307-13. Few adverse effects of long-term creatine supplementation in a placebo-controlled trial.

"Although oral creatine supplementation is very popular among athletes, no prospective placebo-controlled studies on the adverse effects of long-term supplementation have yet been conducted. We performed a double-blind, placebo-controlled trial of creatine monohydrate in patients with the neurodegenerative disease amyotrophic lateral sclerosis, because of the neuroprotective effects it was shown to have in animal experiments. The purpose of this paper is to compare the adverse effects, and to describe the effects on indirect markers of renal function of long-term creatine supplementation. 175 subjects (age = 57.7 +/- 11.1 y) were randomly assigned to receive creatine monohydrate 10 g daily or placebo during an average period of 310 days. After one month, two months and from then on every fourth month, adverse effects were scored using dichotomous questionnaires, plasma urea concentrations were measured, and urinary creatine and albumin concentrations were determined. No significant differences in the occurrence at any time of adverse effects due to creatine supplementation were found (23 % nausea in the creatine group, vs. 24 % in the placebo group, 19 % gastro-intestinal discomfort in the creatine group, vs. 18 % in the placebo group, 35 % diarrhoea in the creatine group, vs. 24 % in the placebo group). After two months of treatment, oedematous limbs were seen more often in subjects using creatine, probably due to water retention. Severe diarrhoea (n = 2) and severe nausea (n = 1) caused 3 subjects in the creatine group to stop intake of creatine, after which these adverse effects subsided. Long-term supplementation of creatine did not lead to an increase of plasma urea levels (5.69 +/- 1.47 before treatment vs. 5.26 +/- 1.44 at the end of treatment) or to a higher prevalence of micro-albuminuria (5.4 % before treatment vs. 1.8 % at the end of treatment)."

[hpb]

Tack så mycket.