The diet of the average Mongol would certainly contain more protein than the diet of say the average Chinese and Persian peasant. This is because while these conquered groups were agriculturalists the Mongols were pastoralists. Thus the base of the former's diet would be bread or rice. In contrast the base of the average Mongols diet would be meat and milk although poorer Mongol, including Genghis Khan as a child, would eat more fruit and vegetables. As a result it may well have been the case that the Mongols were on average more muscular than the people they conquered, some have even gone so far as to speculate this might have given a military advantage.

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