Each of Earth’s life forms, from animals (including humans), plants, fungi, and even cyanobacteria, has a built-in biological clock that functions over a 24-hour cycle.

This so-called circadian clock is a well-structured biological process, which helps keep our bodies healthy and working by regulating tasks such as sleeping, waking, hormone release, body temperature, and other important functions.

(Photo: Chris Beach via Flickr)

(Photo: Chris Beach via Flickr)

Now, a group of scientists at Chicago’s Northwestern University Feinberg School of Medicine has developed what they call the first simple blood test that will tell what time it is, according to your body’s internal clock.

For example, the clock on the wall may say its 5:00PM, but your internal circadian clock may read 3:30AM.

Called TimeSignature, its developers say that the test will provide researchers new insight into the impact of unsynchronized internal clocks on a wide range of diseases.

One day, when it is available for clinical use, the TimeSignature test could help your doctor determine when you should be taking your medications as well as other important health decisions.

“This is really an integral part of personalized medicine,” says study coauthor Dr. Phyllis Zee, chief of sleep medicine in neurology at Feinberg and a Northwestern Medicine neurologist in a press release.

A paper detailing the researcher’s findings has been published in the Proceedings of the National Academy of Sciences (PNAS).