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Ed Yeates ReportingA drug given to horses to control asthma has suddenly and dangerously become what human dieters call their "size zero" pill. While this animal drug seems to work for those wanting to lose weight, it's an extremely risky option.
The drug, called Clenbuterol, is only legal for use in horses, but on the Internet it's easy to buy. The product has even been adapted for easy consumption by humans.
For exercise or racing horses, liquid Clenbuterol is simply injected into the horse's mouth. It immediately opens airways, treating congestion and complications from asthma. Decades ago, athletes, especially body builders, discovered this animal drug increased protein synthesis - preserving and building muscle mass. It also had another seemingly beneficial side effect by triggering fat cells to release fat.
Though Clenbuterol is now banned in professional sports in both Europe and the US, the Internet has suddenly opened a new door for would-be dieters to buy the stuff. University of Utah exercise physiologist Bryan Haycock says beware of the chemical receptors in this drug. What's prescribed for horses is not prescribed for humans.
Bryan Haycock, University of Utah Exercise Physiologist: "These receptors on the heart cause the heart rate to accelerate and blood pressure to increase. And this is something we familiearly know as the fight or flight response."
Watching what you eat and exercising is the way to lose weight. But taking Clenbuterol - so the body is continually under the fight or flight stimulation 24 hours a day - is asking for trouble. Haycock says there's something else that happens too. The fat cells eventually become immune to the drug, what exercise physiologists call a "down regulation."
Bryan Haycock: "And the consequence is the drug no longer works. Your appetite returns and your fat cells are in the mode of storage and you'll rebound."
And rebound you will, regaining weight even faster. Clenbuterol in high doses, which dieters often need to get results, can also increase the risk of stroke and heart arrhythmia.
