From people claiming to be 130 years old to lying about their age in order to compete in the Olympics, lying about how old you are is a age old past time. Now however the next time you claim it’s your “29th birthday” your friends can snag a swab of your spit to prove you wrong.
This remarkable finding was made by researchers at UCLA. They found that the DNA contained in a person's saliva undergoes changes as a person gets older. One of the building blocks of DNA experiences a process known as methylation, which alters its appearance over time and can be used to estimate precisely how old a person is.