Which creatine and protien supplements contain GPA & G-amine

[CanthookitLs6]

I think it would be nice to create a list of these potentially dangerous supplements.

Article Summary

— Research suggests that once fully loaded, only minimal amounts of creatine are needed to maintain the muscle’s loaded state.

— Research suggests that creatine usually needs to be taken only after workouts (see Caveat).

— Reducing creatine intake may serve to prevent muscle creatine transporter downregulation.

— More active and muscular individuals may need to consume greater quantities to maintain intramuscular creatine levels.

— Adding a little sodium to your creatine containing drink may enhance its uptake.

— Guanidinopropionic Acid (GPA) and Glycocyamine (G-amine) are potentially dangerous compounds appearing in several supplement products—GET THE WORD OUT.

— Use these guidelines to tailor your optimum creatine intake protocol, and be wary of accepting any info as dogma.


Full Article
The Naked Truth
Dangerous Creatine
by David J. Barr

When we created Testosterone , one of our goals was to act as a sort of watchdog for the sports supplement industry. So far, we've done a pretty good job. We've exposed frauds, cut through the hype, and provided readers with the info they need to make smart supplement choices.

Now we'd like to take our role one step further. From now on, we'll be regularly reviewing supplements from various companies. If we feel they're worth buying, we'll let you know. If they stink, we'll tell you that too.

But can we review supplements in an unbiased manner given *****'s relationship with Biotest? You bet we can! Of course, with all the new people just discovering *****, we'd also like to use this series to spotlight some of our own products as well, but ideally we'd get an outsider to write those reports. Unbiased, fair reviews: that's what this new series is all about!

Our first installment reviewed Udo’s Choice (a fatty acid supplement). This second installment is about something that’s been written about ad nauseum: creatine. Yes, we know that creatine is practically passé now, given all the exciting new supplement trends, but when new info surfaces or new attitudes toward it arise, we’re gonna’ talk about them. Hence this article by Dave Barr. Read it and look at creatine through fresh eyes.


Think you know everything there is to know about creatine? THINK AGAIN! After all these years, most people STILL aren’t getting the maximum benefit from creatine supplementation. Not only that, but they’re wasting their money while doing it.

Current methods may not only enhance uptake but can help preserve the creatine transporter and save you some cash at the same time. Most importantly, there’s a creatine product on the market that not only makes you slower and weaker, but also may be harmful to your health…you NEED to know about it!


An Orgy of Excess

I’m still amazed that people use so much creatine, especially with all of the data showing how little we actually need. One study showed that after loading, muscle creatine levels were maintained on 0.03g/kg creatine each day (Hultman et al., 1996). This means that a resting 220—pound athlete could maintain creatine levels on a mere 3g/day (and most people using creatine are nowhere near this size)! Keep in mind that this doesn’t not mean that a 100kg guy absolutely needs 3g/day; it simply means that this is as low as researchers have gone while still maintaining elevated levels (i.e. it seems to be the upper limit of what we need).

Now let’s think about this, if most of us will need less than 3g of creatine a day, and we’re probably going to get around 1g from the meat in our diet, this leaves 1-2g a day that we need to supplement. This is supported by another study where weight training subjects ingested the standard maintenance dose (5g/day), and excreted nearly all of it (~4g/day) (Vandenberghe et al., 1997).

In other words, the subjects could only use a gram of supplemented creatine each day! If this seems like a very low amount, you’re absolutely right! In fact, this amount is so low that we probably don’t even need this additional daily supplementation!

Now you’re thinking, "Whoa Dave, all that creatine has gone to your head! That dosing schedule would mean that we don’t need to use it at all!" Not so, because we’d still need to supplement after our workouts. If you’re working out and using creatine 4-5 times a week, then you’d only be missing a few days a week of loading, and any minor dips in muscle creatine levels would be bumped back up to max on training days.

Any decreases in muscle creatine would be negligible, considering that muscle creatine levels are still slightly elevated a full month after supplementation has been completely stopped (Vandenberghe et al., 1997; Hultman et al., 1996). Even if we assume that muscle creatine levels return to normal at the end of the month off, this means that we only lose an average of ~3% of our extra creatine each day —certainly not enough to make a difference, especially when we take into account the training effect.


Let’s Get Physical

Let’s get really theoretical and consider what happens to our creatine levels following a workout. Physical activity enhances our ability to elevate intracellular creatine levels through supplementation (Harris et al., 1992; Vandenberghe et al., 1997; Derave et al., 2003). Taken together, these studies suggest that training may enhance creatine uptake by an additional 10%. If this increase in intracellular creatine is caused by a transient increase in creatine transport, then it means that we can only get this kind of a boost after a workout.

Applying this theory, if we worked out yesterday, we can assume that our creatine levels are about 110% of what they’d be if we weren’t working out. Now if we don’t work out today, and our creatine levels can drop by the "standard" 3%, this means that we’re still 7% above what we could achieve through normal resting supplementation (i.e. not having worked out today).

So, what would happen if we loaded in more creatine on this rest day? Absolutely nothing, because we didn’t have the workout to boost creatine transport and we already have more creatine than our muscles can normally take up. In other words, when we’ve supersaturated our muscles with creatine, it takes a drastic event (like training) to keep them supersaturated. While largely theoretical, this outlines yet another reason why you may not need to add creatine on your off days.

You may be asking yourself why you’d even want to decrease your creatine intake, and the first reason is obviously CASH. While, creatine may not be the most expensive supplement in the world, every little bit of money saved definitely helps. (Of course, just think what you could have done with this info back in the days when EAS was charging something like 70 bucks for a 100 gram bottle!) Some may even rationalize that the money saved on creatine could be put towards more expensive supplements. The most important reason, however, lies below…


Save the Transporters!

I was thinking about starting a new fanatical group called "save the transporters" to fight against excessive creatine use. We’d have rallies and T-Shirts and everything! Unfortunately, club president John Berardi’s T-shirt didn’t have those fake muscles painted on the way he likes, so the whole club folded. Now all I’m left with are two things: 1) memories of JB ranting about people finding out his "skinny secret," and 2) the main reason for not "abusing" creatine. This lies in the fact that using less creatine means that our bodies have less excess to deal with. While I am not-for-one-second suggesting that creatine is hard on our body (in fact, a recent study supports the lack of toxicity—Kreider, 2003), why throw in excess if it’s not going to have any benefit?

I will, however, state for the record that perpetually hammering our bodies with excess creatine may have one unfortunate side effect: creatine transporter downregulation. Creatine transporters are the proteins that allow creatine to enter into muscle. They bind creatine on the outside of the muscle cell and carry it across the cell membrane to the intracellular space.

Now we’ve all heard that these creatine transporter proteins would decrease in number with our creatine use (Guerrero-Ontiveros and Wallimann, 1998). In essence, this could occur because our body detects that we already have too much creatine in our muscle and it wants to minimize further transport—almost the same way our bodies drop our natural T levels while using steroids . This would result in less creatine in the muscles and subsequently less cell hydration, as well as a reduction in performance enhancement.

Well, it’s time for some GOOD NEWS: a recently published study showed that there was no change in the number of creatine transporters when people used typical creatine dosages for up to 2 months (Tarnopolsky et al., 2003). The earlier study showing the transporter downregulation (Guerrero-Ontiveros and Wallimann, 1998) used rats consuming roughly 1g/kg/day, and using our 100kg athlete, that would mean consuming 100g of creatine a day!

So this means that as long as we don’t go through a kilo of creatine a week then we’re home free, right? Well, maybe not. As great as this is for us, we have to be aware of the limitations of the research. The study in question only examined a maximum of 10g/day, 6 days a week, for 2 months. This means that several months after loading, we may still be susceptible to transporter downregulation—we just don’t know.

Logically speaking however, the less excess we have, the better the chance of staving off any reduction in transporters and keeping the benefits of creatine supplementation.


Berardi’s Bulges (not what you think)

As always, one’s individuality needs to be considered when designing any type of program—and this creatine supplementation regime is no different. I managed to speak with Berardi about his creatine intake, and he mentioned that he notices a greater uptake of muscle creatine when consuming higher doses for short periods of time. Occasionally, he’ll go as high as 10-15g a day for a few weeks of very hard training, but most of the time he consumes ~3g/d. This serves to emphasize the idea that you may not be able to universally apply every theory, despite the scientific evidence behind it.

Having said that, most people do not have the training intensity/volume/frequency that he does, or the same quantity of muscle. Once you achieve a similar level of training and muscle mass, greater quantities of creatine may be warranted. For those of us not at those levels, this type of occasional loading (aka periods of higher creatine intake) every few months can be experimented with. Most importantly, use these guidelines to determine what works bets for YOU!


Jack Up the Sodium

Another worthwhile way to improve creatine "efficiency" is to improve its uptake in muscles. While everything seems to have been tried already, the simplest method remains. Remember the creatine transporters we just discussed? Well we still don’t have the full picture on them: they transport not only creatine into the muscles, but sodium as well (this is called co-transport, i.e. 2 things at once). In fact, it is only because of the sodium that the creatine gets into the muscles at all!

In order to illustrate the importance of this, one study demonstrated that muscle creatine uptake was more dependent on sodium than insulin (Willott et al., 1999)! We all know how important insulin is for creatine uptake, so discovering the importance of sodium is an exciting find! This doesn’t mean that you should start loading tons of table salt into your post-workout drinks, but it means that you should be aware of the need for sodium for creatine uptake.

Another study went one step further and measured the amount of sodium needed for maximal creatine uptake in rats. Researchers once again found that sodium was more important than insulin, and muscle creatine content peaked with high-normal blood sodium levels (Brault and Terjung, 2003). Elevating blood sodium greater than high-normal concentration had no additional effect, but we already have the info we need to maximize creatine levels!

During a hard hour-long workout we can lose over a gram of sodium in our sweat alone! Now think about the fact that we can drink almost 3 liters of water in the hours surrounding our workout, with pre/post meals and the water we drink during the workout. This fluid intake dilutes our blood electrolytes, and coupled with the sweating, our sodium levels aren’t going to be at the optimal level for maximum creatine transport! One way to beat this problem is to throw a little sodium into your drink during your workout. Also, having a little table salt in your post workout drink will help ensure that you’re topped up and the creatine is flowing well.

As for what quantity to take, you don’t have to go nuts at all, but you need to be able to judge for yourself based on how much you sweat. Personally, I sweat a fair amount and used to use a quarter of a teaspoon during an hour-long workout. Now, having moved to Texas from Canada, I sweat my ass off all day long and have subsequently increased the total table salt quantity to 1/3-1/2 a teaspoon (about 150mg), depending on the workout. The best advice would be to start small and work up to see how it goes.


Dangerous Creatine?

No, this isn’t the tagline for a new type of creatine, it means that there’s a semi-popular creatine-like product on the market that may actually be harmful to your health. What’s worse is that there are now several copycat products on the market as well! As if that wasn’t bad enough, one of the potentially dangerous compounds (oh yes, there’s more than one!) that this product contains is ergolytic; i.e. something that decreases athletic performance.

This potentially dangerous ergolytic chemical is Guanidinopropionic Acid (GPA), which binds the creatine transporter and plugs it up so creatine can’t be transported into various tissues (similar to the concept of tamoxifen blocking the estrogen receptor, not allowing estrogen to bind). This is a problem, because most of our tissues can’t make creatine so it has to be transported in, and blocked transporters means a reduction in cellular creatine levels.

Bear in mind that creatine isn’t just a supplement, it’s a naturally occurring substance in our bodies that we need to survive! You know the impact of having 20% more creatine, now imagine having 80% less creatine! GPA induced creatine depletion can not only reduce muscle strength after a mere seven days of consumption (Gagnon et al., 2002), but has also been shown to convert fast-twitch muscle to slow-twitch (Ren et al., 1995)! So this substance might make you weaker and slower!

While these consequences should be enough to make you avoid supplements containing this chemical, there’s also a potentially dangerous side to consider: both our hearts and our brains have creatine transporters!!! Any time you start to mess around with our two most vital organs, it can’t be good. Fortunately, the brain seems to temporarily compensate for decreases in energy supply caused by GPA (O'Gorman et al., 1996), but do we really want our bodies to have to adapt to reduced energy levels? Of course not!

We also don’t want our hearts to be affected by GPA supplementation, but they are! In fact, 3 different studies showed that creatine levels in the heart dropped by 80-87% with GPA consumption in rats (Boehm et al., 2003, Neubauer et al., 1999; Horn et al., 2001). Now you can see why it’s nearly impossible to perform human studies using this substance! Clearly, you have to wonder what the manufacturers were thinking when they approved production of this supplement.

"But wait, there’s MORE! Order now and you’ll get another potentially dangerous ingredient for free!" One particular supplement ("SWOLE") combines GPA with another potentially dangerous substance known as Glycocyamine (G-amine). Sadly, G-amine (also known as guanidinoacetate) has been picked up by a few different supplement companies who obviously don’t do any research on what they’re getting people to ingest.

The reason G-amine is so popular (from a marketing standpoint, not from the consumers’) is because it is the precursor to creatine. Just like Testosterone can come from andro, creatine comes from G-amine. The theory is that you jack up G-amine levels and you get a whole bunch more creatine. The really asinine part is that, you can just directly take creatine!

We can’t take Testosterone due to legal reasons, so we have to find other ways to increase its levels—enter prohormones (among other effective things). But for our purposes, there’s no reason to worry about creatine precursors because we can just take the substance directly. The whole precursor concept is really hot when it comes to marketing to laymen, which is where this supplement takes off.

Unfortunately, consuming this chemical seems to have the undesirable effect of elevating blood levels of a substance called homocysteine, which is a very strong risk factor for cardiovascular disease (Stead et al., 2001). Cardiovascular disease is easily the number one killer in the Western World, and the last thing we need to do is increase our risk for it. Conversely, taking creatine decreases homocysteine levels, raising even more therapeutic possibilities for this supplement. As if to spit on your grave, if you’re supplementing with creatine, G-amine may also decrease its uptake by muscles (Zugno et al., 2003).

Sadly, the FDA has already spoken to the company that produces this "combo of harm," because another of its supplements caused liver damage… you’d think that they would have learned. Unfortunately, these substances aren’t just isolated to a single product—they’re popping up in all kinds of different supplements (including some protein powders)! It’s my opinion that products containing either of these substances should be pulled off the market and the formulas changed, but the FDA can’t do anything until harm has already been done. This means that it’s up to us to spread the word about these substances. Most importantly, before you supplement with something, do your research and KNOW WHAT YOU’RE CONSUMING!




Special thanks to: Chris Shugart, John Berardi, Mark Young, and my advisor David Lounsbury.

David J. Barr BSc. CSCS has spent the past 4 years as a Varsity Strength and Conditioning Coach at the University of Waterloo. His current PhD work involves amino acid supplementation, muscle protein synthesis, and resistance exercise at the University of Texas Medical Branch. Future research prospects include the cellular basis for muscle breakdown, as well as muscle physiology for NASA. He may be contacted at [email protected] (be sure to include the word "*****" in the subject line)


References

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Creatine transporter activity and content in the rat heart supplemented by and depleted of creatine. Am J Physiol Endocrinol Metab. 2003 Feb;284(2):E399-406.

Brault JJ, Terjung RL. Creatine uptake and creatine transporter expression among rat skeletal muscle fiber types. Am J Physiol Cell Physiol. 2003 Jun;284(6):C1481-9

Derave W, Eijnde BO, Verbessem P, Ramaekers M, Van Leemputte M, Richter EA, Hespel P. Combined creatine and protein supplementation in conjunction with resistance training promotes muscle GLUT-4 content and glucose tolerance in humans. J Appl Physiol. 2003 May;94(5):1910-6.

Gagnon M, Maguire M, MacDermott M, Bradford A. Effects of creatine loading and depletion on rat skeletal muscle contraction. Clin Exp Pharmacol Physiol. 2002 Oct;29(10):885-90.

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Horn M, Remkes H, Stromer H, Dienesch C, Neubauer S. Chronic phosphocreatine depletion by the creatine analogue beta-guanidinopropionate is associated with increased mortality and loss of ATP in rats after myocardial infarction. Circulation. 2001 Oct 9;104(15):1844-9.

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Neubauer S, Hu K, Horn M, Remkes H, Hoffmann KD, Schmidt C, Schmidt TJ, Schnackerz K, Ertl G. Functional and energetic consequences of chronic myocardial creatine depletion by beta-guanidinopropionate in perfused hearts and in intact rats. J Mol Cell Cardiol. 1999 Oct;31(10):1845-55.

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Stead LM, Au KP, Jacobs RL, Brosnan ME, Brosnan JT. Methylation demand and homocysteine metabolism: effects of dietary provision of creatine and guanidinoacetate. Am J Physiol Endocrinol Metab. 2001 Nov;281(5):E1095-100.

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Acute and moderate-term creatine monohydrate supplementation does not affect creatine transporter mRNA or protein content in either young or elderly humans. Mol Cell Biochem. 2003 Feb;244(1-2):159-66.

Vandenberghe K, Goris M, Van Hecke P, Van Leemputte M, Vangerven L, Hespel P. Long-term creatine intake is beneficial to muscle performance during resistance training. J Appl Physiol. 1997 Dec;83(6):2055-63.

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Creatine Metabolism in Skeletal Muscle

III. SPECIFICITY OF THE CREATINE ENTRY PROCESS JBC 243(8) 2024-27 (1968) Coy D. Fitch 1, Robert P. Shields 1, William F. Payne 1, and Judy M. Dacus
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