Zearalenone and zeranol
If you’ve been following my blog then it’s hopefully become clear to you that the threat mycotoxins pose is real. If, however, you’re still in doubt about the danger, allow me to share two brief stories of zearalenone and zeranol.
Do you know what you really have on your plate?
The US Anti-Doping Agency has recently stripped a runner Ajee Wilson of a record for 800 m due to being tested positive for zeranol – a substance banned in sport and classified as a performance-enhancing drug. Interestingly, no further action against the athlete was taken, since she managed to provide compelling evidence that the positive test was caused by contaminated beef.
In a similar case in 2014 Chinese hammer thrower Zhang Wenxiu was tested positive for zeranol two days before winning her gold medal at Asian Games. She was initially disqualified and the Olympic Council of Asia withdrew her gold medal. In a further investigation the decision was overturned as the positive testing result was attributed to food contaminated with zearalenone.
Neither of the above athletes was aware that they had been consuming tainted food, yet they both met severe consequences of their respective diets.
What, then, are zearalenone and zeranol? Are they dangerous? Why are they banned in sports? How do they end up in our food? Should we be concerned? Let’s find out!
Zearalenone and zeranol as oestrogenic mycotoxins
Zearalenone is a mycotoxin produced by Fusarium fungus which is known to contaminate cereals like corn, wheat, barley, oats, and rye. Once consumed, the toxin can easily be transformed into one of the numerous chemical compounds with similar structures and properties – zeranol being of our particular interest. Now, here is a worrying part: both zearalenone and zeranol are oestrogenic. They aren’t hormones per se, but because they can bind to estrogen receptors they are capable of tricking our bodies to take them for hormones and effectively to cause hormonal changes.
So, what do they do?
You know well that oestrogens are naturally produced by human bodies. You’re also aware that the all-important hormonal balance in our bodies is responsible for digestion, respiration, growth, reproduction and much more. To make long story short, hormones control these processes by interacting with special receptors on the surface of our cells, and this all makes for a very fragile and delicate balance.
But apart from oestrogens produced in our bodies there are also the ones occurring in the natural environment, like phytoestrogens (produced by plants) or mycoestrogens (produced by fungi, such as zearalenone). Last but not least, there are synthetic oestrogens that can be manufactured in laboratories. These may be used as medicines in hormonal disorders treatment to restore that precious hormonal balance. Also, because zeranol is the most oestrogenic of all zearalenone metabolites, it has been used in veterinary medicine. In some countries such as the United States, it is still allowed to use special implants in livestock that slowly release zeranol into their bodies (in the European Union these so called growth-promoting agents are illegal). This results in increased rate and efficiency of muscle growth in animals, but it remains unclear to us how this mechanism works. As zeranol helps grow muscle tissue in animals, it naturally attracted attention of some of the most devoted bodybuilders years ago. However, the reports regarding prolonged exposure to this toxin in bodybuilding were mostly telling the story of serious health issues related to oestrogenic effects, rather than impressive biceps and pectorals.
Does it concern you?
Of course it does! Since our hormonal balance is such a fragile one, you’d be right to assume that we should best avoid anything which might potentially disrupt it. That means staying away from unwanted hormones – of either synthetic or natural origin – in your food. You see, if a cow is treated with a zeranol implant, then unless a meet producer hasn’t waited with slaughtering the animal long enough, the traces of this toxin could still be found in your steak. Similarly, if you have your milk and cereal breakfast, and the crops your meal is made of have been contaminated with one of the Fusarium fungi, chances are that the unwanted oestrogenic mycotoxin enters your system. It may seem like pure theory, but do you still remember both athletes who tested positive for zearalenone? I’m sure they wished back then that testing for the presence of the mycotoxin in their food had been more thorough…
And so should you! That is unless you would like to risk being exposed to potentially cancerogenic substances, or if you’d rather suffer from some nasty fertility disorders or from hormonal imbalance or… As it is the case with most mycotoxins, the list of adverse effects they may cause is long and terrifying.