NADA fear that athletes may risk ingesting clenbuterol, a steroid that is used to fatten pigs and calves before they are sent to slaughter.

“The consumption of meat should therefore, if possible, be avoided, and the alternatives should be discussed with the nutritionist,” said NADA in their newsletter today.

The risk of clenbuterol contamination in meat produced in China has long been mentioned by anti-doping agencies, although no recent cases have been reported.

Clenbuterol made headlines in the past when cycling champion Alberto Contador tested positive on the 2010 Tour de France.

The Spaniard has always maintained that he was contaminated by eating a steak bought in Spain.

Contador, however, was suspended and stripped of several titles including the 2010 Tour de France and the 2011 Giro d’Italia.