When it comes to revealing someone's age, spit may be an indicator.
UCLA geneticists have developed the saliva "age" test, according to the university's online newsroom. The process was developed through research on how DNA changes as people age.
"With just a saliva sample, we can accurately predict a person's age without knowing anything else about them," said Dr. Eric Vilain, the principal investigator and UCLA geneticist.
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Vilain and his team were able to pinpoint a person's age within five years, "an unprecedented level of accuracy," according to UCLA.
The saliva test could become a new forensic tool to narrow down the age of a suspect, said Vilain. Doctors could use the test to personalize medical treatment when it comes to age-related diseases, he said.
The complete findings appear in the online journal of the Public Library of Science.