If you are a regular gym-goer, chances are you have heard of creatine. Creatine is one of a few supplements that have proven to improve your ability to lift weights and build and maintain muscle. However, it does boost levels of creatinine which must be excreted by your kidneys.
To answer the question of whether or not creatine supplementation can damage kidneys let’s take a look at what creatine does in the body. Your muscles, brain, heart, and many other tissues use creatine to regenerate Adenosine Triphosphate (ATP) which is THE energy currency for ALL cells.
Cells are constantly generating ATP because it cannot be stored, and there are several different cellular pathways used to insure there is a constant supply of ATP to keep the cell alive. When you are doing any kind of resistance training and training to momentary muscular failure the muscle cells have to generate a lot of energy very quickly and they use creatine heavily to continue to generate ATP to do the work.
Having adequate creatine is crucial for resistance training and creatine supplementation has conclusively been shown to be HIGHLY effective for resistance training, increasing strength, and building muscle.
A by-product of creatine in the cell’s energy cycle is creatinine which must be excreted by the kidneys. Creatinine levels are the most commonly used indicator of kidney function: in general, if your levels are high – there is an issue with your kidney function.
Muscles contain more than 90% of your creatine stores, so the more muscle you have, and the more you use that muscle, the more creatinine you produce. And so it should not be too surprising that supplemental creatine increases your blood levels of creatinine beyond the normal range.
But does that fact that supplemental creatine increases creatinine mean it is causing damage to your kidneys? The short answer is that in anyone with healthy kidneys the answer is a definitive NO! Creatine supplementation has been studied both short and long and term and there is no evidence it will cause any harm in anyone with healthy kidneys, and evidence shows there is no adverse effects on kidneys.
Healthy people can get all the performance enhancing benefits of creatine with just 3 – 5 grams per day and there may be some benefit to taking up to 10 grams for short intervals. However, this higher dose may cause false positive in creatinine blood tests.
For people with kidney issues it is best to avoid creatine supplements altogether to be on the safe side.
Creatine and Vegetarians
Supplementing with creatine can be highly beneficial for vegetarians and vegans because the only way you obtain it through your diet is eating meat. When a group of vegetarians supplemented with creatine for 8 weeks, they had a big increase in bench press strength and whole-body muscle mass!
Creatine and Improved Brain Function
Yes – you read that right! Creatine supplementation can improve brain function.
A 6-week placebo-controlled, cross-over trial concluded that “Creatine supplementation had a significant positive effect (p < 0.0001) on both working memory (backward digit span) and intelligence (Raven's Advanced Progressive Matrices), both tasks that require speed of processing. These findings underline a dynamic and significant role of brain energy capacity in influencing brain performance.”