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 By: David Barr
Although bringing you to the cutting edge is usually very exciting, there's a darker side that must often emerge: when I have to don the mask and become sports nutrition's Mythbuster. Sure I've created some of the most prominent tombstones in the graveyard: glutamine, arginine (a.k.a. "nitric oxide"), anti-creatine, and even the post-workout window have fallen to my blade. But every time there's a backlash, as companies scramble to bury the data, younger individuals get angry as their underdeveloped prefrontal cortices hold reason captive. But this time it's worse. This time, I may have inadvertently helped create the myth. It's the myth of Waxy Maize Starch (WMS), and it's time for me to pay the price.
  Click Image To Enlarge.It's Time For Me To Pay The Price.
Before we get to the actual myth, we should take a look at what we're talking about. In fact, some of the mythology lies in the fundamental misunderstanding of what WMS really is. Waxy starches are carbohydrates derived from various sources such as rice, barley, and corn (i.e. maize). The "waxy" part refers to the fact that under a microscope there exists a resemblance to actual wax, although this it does so in appearance only. The main characteristic of waxy starches is that they generally contain a large amount of highly branched starch called amylopectin. Specifically, waxy starches are defined as having an exceptionally high amylopectin content - the remaining being comprised of the less branched amylose (8, 12).
Considering that many of us have used WMS specifically for the purposes of post-workout glycogen restoration, you may be interested to know that the highly branched glucose subunits of amylopectin essentially make it the plant version of glycogen. Amylose on the other hand, is less branched and in theory, more slowly digested (3, 13, 15). The reason behind their relative digestion rate is due to the fact that enzymes have greater access to the glucose subunits in the highly branched structure. At least that's how it should work. It's worth noting that along with the degree of branching comes the giant molecular weight of amylopectin, which contributes directly to the mythology.
  Click Image To Enlarge.WMS Magnified 400X And By TEM.
Now that we understand what we're talking about, it's time to look at the actual tale. Essentially, the myth states that WMS is a very fast carbohydrate because of its high amylopectin component (>99%), and subsequent enormous molecular weight (this explains why some companies simply call their WMS "amylopectin"). It's further stated that because of this molecular weight, WMS is absorbed by the gut more quickly than dextrose or maltodextrin -the archetypical "fast carbs"- which in turn results in much greater glycogen storage. Some claims go so far as to specify that WMS is absorbed, or will restore muscle glycogen, ~70-80% faster than other quick sources. Unfortunately, these claims just cannot be substantiated. In fact, there are very few studies even performed on WMS, and they're not at all what you might expect. Fortunately, the earliest research on WMS not only used exercise, but did so in trained athletes, making their results more relevant. Let's take a closer look.
 Click Image To Enlarge.Amylose & Amylopectin.
The first study compared way maize to dextrose, slow starch, and a placebo (4). In contrast to common claims, following ingestion, both blood glucose and resulting insulin levels were similar between WMS and slow starch, and 3 times lower than plain dextrose. Measured work output during cycling exercise was not different following either dextrose or WMS ingestion, which were similar to slow starch.
Once again, WMS performance contradicted the frequent claims about apparent rapid absorption. This time, blood glucose levels were not only lower than maltodextrin, but lower even than the slower carbohydrate sucrose. In fact, the glycemic response of WMS was low enough for researchers to call it a "low-glycemic-index treatment", like the slow starch.
Interestingly, the resulting blood glucose response of WMS was similar to that of bread! As you'd expect, this was quite a bit lower than the fast carb mix of maltodextrin + sucrose. Additionally, the insulin response was significantly lower for WMS even compared to the bread treatment (and of course much lower than maltodextrin).
Although a full discussion is beyond the scope of this article, it's worth noting that simply measuring blood sugar isn't ideal for a complete understanding of this substance. Adding insulin measurements helps a great deal, although this is still not perfect (for a full review, see 14).
Looking at the above summaries there seem to be discrepancies. After all, the responses range from being slightly worse than dextrose (5), to much worse than dextrose (4) or sugar and maltodextrin (1), to even worse than bread (10). While none of these probably make you want to use WMS, or support the predominant claims about it, the differences are enough to make you wonder what's going on. After contacting National Starch and Chemical Company (NS) I discovered that there are different preparation methods for waxy maize. These treatments can change the properties of WMS such that it may be absorbed differently. For example, cooked starch is more readily absorbed than the native uncooked version. I must admit that this gave me a glimmer of hope as I quickly jumped on the idea that any WMS available for sale would only use the fastest "type". Unfortunately this was short lived as the realization set in that the "rapidly hydrolyzed" starch from NS (11), called AMIOCA, actually yielded some of the worst performance results when compared to actual fast carbohydrates (1, 4).
The discrepancies lie in the fact that the "rapidity" was originally determined with digestive enzymes in a test tube (11), or was relative to a very slow starch (1, 11). From this we can see that in contrast to original opinion, amylopectin content is not synonymous with fast digestion or absorption. NOTE: The company themselves have no glycemic data on this product, making this the first (and currently only) literature review of WMS in existence. So the fastest WMS might be almost as good as dextrose or maltodextrin, but how can we be sure what kind we're getting? Naturally you wouldn't expect anyone to admit that they're selling the "slower" types of WMS, and considering the other claims that have been made... Come to think of it, the absence of information available makes me wonder if anyone knows what's being ingested.
To reiterate, not only do the available data fail to support any of the claims made about WMS, they seem to contradict it! At this point I began to feel as though I was missing something. So just to make sure that I covered everything, I contacted 5 of the biggest supplement companies that sell WMS products. Sadly, in spite of their claims, those that actually tried to help me couldn't provide any research on WMS at all. Not exactly a confidence booster. Chances are, if they're reading this report then they're learning right in step with you that there are studies on WMS - and they ain't what they expected...
So where did this myth come from? After all, there has to be something to it if it's as pervasive as it is. The fable was actually created from the erroneous application of two very powerful carbohydrate studies (7, 9). These studies used a carbohydrate extract called Vitargo, and were referenced on the label of a now-defunct product containing this carb. When we looked at the label it was clear that this supplement had derived their Vitargo (which again, is a carbohydrate extract) from... drum roll please... waxy maize! And the myth was born: research showing that Vitargo had rapid gastric clearance and glycogen restoration was equated with the idea that high molecular weight carbohydrates (i.e. WMS/amylopectin) had these properties.
Just take a look at any supposed WMS references, if you can find them, and you'll see at least one of these studies listed: Leiper et al., (2000) or Piehl Aulin et al. (2000). In fact, this is also where the often-specified gastric emptying, rate of absorption, and glycogen resynthesis numbers come from. Perhaps the worst part is that these studies not only used Vitargo, they did not derive it from waxy maize! That's right, the commonly cited WMS data actually used a carbohydrate extracted from potato starch (7, 9). As if to add a final comical exclamation point, the potato starch itself wasn't even the waxy variety. Summary: The most common "information about waxy maize" comes from a carbohydrate extract that wasn't originally waxy nor even derived from corn. This is a worse connection than saying that Nobel Prize-winning research for the discovery of nitric oxide has any relevance for athletes taking arginine!
So in spite of hours of investigation, I just couldn't find any reason to use WMS. Even speaking to a dozen or so people from the companies that sell it, couldn't provide me with one single study about this substance. Worse than simply not being able to justify claims about its rapidity, most of the available information suggests that WMS is a poor carbohydrate to use after training. To put all of this in perspective, it's possible that the WMS we're using has worse digestive/absorptive properties than white bread. We can hope that our product contains "faster" WMS, which will undoubtedly become the new claim, but even at best this is similar to dextrose and maltodextrin. Considering that dextrose is the cheapest supplement in existence, this begs the question: what are we paying for?
To date, there are no comparison gastric emptying studies with WMS. Lastly, don't forget that this is an investigative literature review, not an opinion piece.
About The Author:
He holds certifications with the NSCA as well as USA Track and Field, and is the Official supplement consultant for Super Human Radio. He can be contacted through his website: http://www.RaiseTheBarr.net. References:
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