Remember that Seinfeld TV episode? It inspired one researcher to find out if double dipping is bad for you.
The study that will appear in the Journal of Food Safety found, on average, three to six double dips transferred about 10,000 bacteria from one eater's mouth to the remaining dip.
The kind of dip made a difference.
Salsa picked up higher initial numbers of bacteria than cheese or chocolate because it was runny. The thicker the dip, the more the bacteria stuck to the chip.
Researchers say double dipping appears unlikely to be a major public health threat, but it's good to be aware that sharing a bowl of dip can mean sharing more than you'd like.