We hypothesized initially that the benefit of spices might lie in their anti-microbial properties. Those compounds in spice plants which compounds in spice plants which give them their distinctive flavours probably first evolved to fight enemies such as plant-eating insects, fungi, and bacteria. Many of the organisms which afflict spice plants attack humans too, in particular the bacteria and fungi that live on and in dead plant and animal matter. So if spices kill these organisms, or inhibit their production of toxins, spice use in food might reduce our own chances of contracting food poisoning.