The present disclosure is directed to rubber compositions comprising a butyl rubber or a halogenated butyl rubber, at least one filler, and a whey protein component. The whey protein component is present in an amount sufficient to provide about 0.1 to about 10 phr whey protein in the rubber composition. The present disclosure is also directed to methods of preparing such rubber compositions and to a tire innerliner or innertube containing the rubber compositions disclosed herein.