The NFL is warning players about eating meat from China and Mexico that might be contaminated.
In a letter which was shared on social media by at least two players - Arizona's Patrick Peterson and Baltimore's Steve Smith - the NFL Players Association reminds players they are ultimately responsible for what they put in their bodies.
"There is some evidence that some meat produced in China and Mexico may be contaminated with clenbuterol, an anabolic agent which is banned by the NFL Policy on Performance-Enhancing Substances," the letter reads.
"Consuming large quantities of meat while visiting those particular countries may result in a positive test for clenbuterol in violation of the Policy.
"Please take caution if you decide to consume meat, and understand that you do so at your own risk."
Houston Texans left tackle Duane Brown's story should serve as a cautionary tale for all athletes that might be subjected to fines and suspensions.
Last year, Brown tested positive for clenbuterol after a bye week trip to Mexico. He ate meat while on the trip.
Brown provided receipts of what and where he ate, and after a prolonged investigation, his name was cleared and he avoided a 10-game suspension.
Brown's case wasn't the first involving meat from Mexico.
National soccer team members from Mexico tested positive for clenbuterol in 2011 - those positive results were traced to contaminated meat.
