Dr. John McDougall, using the skeletal remains of Roman gladiators from the ancient city of Ephesus, says that the warriors observed a strict vegan diet, staying away from milk and meat.
"We compared the findings from other skeletons we found buried in the area and found that the remainder of the city's residents who did not engage in fighting had a more varied diet," McDougall says.
According to McDougall, the dietary habits of the gladiators, which consisted heavily of barley products, was not done in the name of "animal rights" but in order to be effective in battle.
"They lived on the most efficient fuel that made them the best fighters that they could possibly be," he said.
According to the Jewish historian, Josephus, in his book The Jewish War, in the aftermath of the Jewish revolt in Judea, 66-73 CE, the gladiator schools received an influx of Jews.