Scientists develop test able to tell what time our body thinks it is

Do you feel most productive in the middle of the day, or are you someone who works best in the wee hours? Whether you're a lark or a night owl actually has very little to do with personal preference and everything to do with your circadian rhythm.

A circadian rhythm is an internal body clock that dictates a person’s sleep/wake cycle; it’s what enables us to feel sleepy at night and energised during the day and offers fundamental insight into how someone’s body functions.

Now, a team of scientists have found a way to measure a person’s circadian rhythm via a computer algorithm calls TimeSignature, which uses blood samples and artificial intelligence data to identify a person’s physiological time i.e. what 'time it is' in their body.

Plenty of research has gone into understanding circadian rhythms as this can help identify when someone will feel fatigue and when certain hormones are released in their body.

A measurement tool such as TimeSignature may also help prevent the disruption of one’s circadian rhythm, which can lead to a series of health problems such as insomnia and heart disease.

“Before we didn’t have a clinically feasible way of assessing the clock in healthy people and people with disease,” explains the study’s co-author Ravi Allada, professor of neurobiology at Northwestern University.

“Now we can see if a disrupted clock correlates with various diseases and, more importantly, if it can predict who is going to get sick."

In order to work, TimeSignature requires patients to take two blood tests 10 to 12 hours apart.

The algorithm then analyses 7,000 genes in the blood samples, examining when these genes peak throughout the course of the day.

This allows it to identify 40 genes which make up the patient’s circadian rhythm.

From there, scientists can predict how strongly those genes will be expressed at different times of the day; comparing this to the actual times that the blood samples were taken allows them to understand what 'time it is' in their body.

If TimeSignature is as effective as the authors believe it to be, physicians could use it to detect the times of the day that certain medications should be taken in order to be most effective, which could be hugely beneficial for treating an array of major and minor illnesses.

“Knowing what time it is in your body is crucial to getting the most effective benefits,” said co-author Dr. Phyllis Zee, chief of sleep medicine in neurology at Northwestern University.

“The best time for you to take the blood pressure drug or the chemotherapy or radiation may be different from somebody else.”

Measuring one's circadian rhythm doesn't just offer physical health benefits, but possibly mental ones too that could significantly boost professional performance.

For example, a recent study found that night owls are far more productive later on in the day, advising these people to actually start their work in the afternoon as opposed to the morning.

Meanwhile, another study of more than 14,000 students revealed that night owls often perform worse academically; experts suggested that these people avoid taking early morning classes.