New Breath Test Tells If You're Kissable

couple kissing. (Image credit:

Many people like to puff a quick breath into their hand to check if they're ready for that face-to-face job interview, or even just ready to pucker up for someone special. Now researchers have developed a pocket-size breath test that can catch a whiff of bad-breath bacteria.

Simply dab some saliva onto the small window of the OkayToKiss kit. A blue result prompts the user to grab a toothbrush, whereas a clear result signals it's safe to get orally intimate.

"OkayToKiss will turn blue if a person has enzymes in the mouth produced by the Gram-positive bacteria," said Mel Rosenberg, a scientist at Tel Aviv University in Israel.  "The presence of these enzymes means that the mouth is busily producing bacteria that foster nasty breath."

The disposable OkayToKiss device is just the size of a pack of chewing gum, and fits easily in pockets or purses. Researchers say that it can encourage better oral hygiene such as flossing or brushing, besides the obvious social benefits and feeling more comfortable before starting to plant a wet one on your beloved.

Scientists previously believed that one type of bacteria, known as Gram-negative, represented the main culprits behind bad breath. However, Rosenberg and Dr. Nir Sterer at Tel Aviv University discovered that Gram-positive bacteria are also partners in crime for causing that open-mouthed stink.

Lab tests grew the bacteria in biofilm layers, and found that the Gram-positive bacteria create enzymes that chop sugary bits off proteins. That makes it easier for Gram-negative bacteria to chow down.

For full details on this finding, check out the March issue of the Journal of Breath Research. Rosenberg is one of two editors-in-chief of the journal.

Biomarkers that appear in OkayToKiss have also appeared in many popular diagnostic kits, notably home pregnancy tests and glucose monitors used by diabetics.

Rosenberg's previous inventions also led to a two-phase mouthwash that has become popular in the UK, Israel and elsewhere. Research has found most over-the-counter mouthwashes to be effective, although some may end up staining teeth.

Rosenberg's upcoming book, "Save Your Breath," summarizes 20 years of his research on bad breath.

Live Science Staff
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