Our digestive systems can process almost anything if necessary, but for optimum nutrition we need a high protein diet. But we absolutely cannot eat foods with a high concentration of salicylic acid. We can't process the chemical so even a small amount is fatally toxic.

[He thinks of how much he should say, taps his fingers against his leg.]

Our evolutionary ancestors lived in packs and were probably telepathically linked. They are known as...well...I suppose the Gallifreyan word for them wouldn't mean anything to you.