Mars spends most of its advertising dollars for its petcare brands — including Pedigree, Cesar and Whiskas — on television, according to the food group's marketing chief.
Andrew Clarke, Mars' chief marketing and customer officer, told CNBC's "Marketing Media Money" program that digital advertising needs to prove that it is effective, just as TV advertising has done.
Mars spends around 60 percent of its marketing budget on TV in its petcare business, while the remaining 40 percent goes on digital ads.
"We really need to prove how our new digital platforms, our media partnerships (work)," Clarke said. "We need to prove that, so it actually does drive sales in the way that we know that sales are driven in a traditional media space."