Russia's World Cup team was told to stay away from "exotic teas" and foreign medicine to avoid testing positive for doping during this year's final. The Russian Football Union issued the recommendations in a series of tweets that also included instructions to be careful with meat from Latin America and China.
"We are proud that Russian football players did not test positive once in the past four years," the RFU said. "It is very important to stay completely clean."
It was not immediately clear why the football federation was using Twitter to publish rules meant to keep players from being banned for cheating. Russia will host the World Cup for the first time from June 14 to July 15.
Its preparations have been shadowed by a doping scandal that resulted in Russians competing under the Olympic flag at this year's Winter Games in South Korea.
Russia has furiously denied charges of running a state programme that helped athletes stay clean before and during the 2014 Winter Games in Sochi. The saga has had wider implications for the World Cup. Deputy Prime Minister Vitaly Mutko was forced to resign as football federation president and step away from tournament preparations after being handed a lifetime Olympic ban in December.