The Channel 9 News station in Denver (NBC) has a fun science segment hosted by Steve Spangler. He and his kids did an experiment to see if that Seinfeld episode was fact or fiction. The episode is where the character of George dips his chip, takes a bite and then dips the bitten chip again. Another character "Timmy" claims that double-dipping a chip is just like putting your whole mouth into the dip. Ewwww!!

First, here is the Seinfeld episode:

Then the science. From Channel 9 News Steve Spangler shows us proof  that double-dipping is not good.