• Shruti GOCHHWAL

Circadian rhythm test

Circadian rhythms are 24-hour cycles that are part of the body’s internal clock, running in the background to carry out essential functions and processes. One of the most important and well-known circadian rhythms is the sleep-wake cycle.

Types of circadian rhythm disorders

circadian rhythm test

women with circadian rhythm disorders, Credits: pexels


Jet Lag Disorder

This occurs when a person crosses multiple time zones in a short period of time and gets its name from the fact that it is often experienced by people who take intercontinental flights. Until a person’s circadian rhythm can acclimate to the day-night cycle of their new location, they are likely to suffer sleeping problems and fatigue from jet lag.

Shift Work Disorder

Work obligations can cause major disruptions in a person’s circadian rhythm. Shift work, which requires having to work through the night and sleep during the day, puts a person’s sleep schedule directly at odds with the local daylight hours.

Advanced Sleep Phase Disorder

People with this type of disruption find that they get tired early in the evening and wake up very early in the morning. Even if they want to be up later at night or sleep later in the morning, people with an advanced sleep phase disorder usually cannot do so.

Delayed Sleep Phase Disorder

This type of circadian rhythm disruption is associated with “night owls” who stay up late at night and sleep in late in the morning.

Non-24 Hour Sleep Wake Disorder

This condition occurs primarily in people who are blind and are not able to receive light-based cues for their circadian rhythm. Their body still follows a 24-hour cycle, but their sleeping hours constantly shift backward by minutes or hours at a time.

Irregular Sleep-Wake Rhythm Disorder

People with this rare disorder have no consistent pattern to their sleep and may have many naps or short sleeping periods throughout a 24-hour day.

Timing is everything, and it also has a huge impact on your health. Now there’s a blood test to better understand your internal time clock and optimize it for better well-being.

A test to check your circadian rhythm

circadian rhythm types

a women in sleep, Credits: pexels


The Time Signature test was developed by researchers at Northwestern Medicine scientists. It requires two blood draws. It offers insights through gene expression markers into the time in your body compared to time in the external world.

For instance, it may be 8 a.m., but your body may be operating as if it’s 6 a.m. Previously, determining a person’s internal clock could only be done by drawing blood multiple times over a specific span.

The test, which measures 40 different gene expression markers in the blood, can be performed any time of day, regardless of the patient’s circadian pattern or level of restfulness.

A Processes in nearly every tissue and organ system in the body are orchestrated by an internal biological clock, which directs circadian rhythm, such as the sleep-wake cycle. Some individuals’ internal clocks are in sync with external time but and others are out of sync and considered misaligned.

The new test for the first time will offer scientists the opportunity to easily examine the impact of misaligned circadian clocks in a range of diseases, from heart disease to diabetes and Alzheimer’s disease. When the blood test eventually becomes clinically available, it also will provide doctors with a measurement of an individual’s internal biological clock to guide medication dosing at the most effective time for his or her body.

The software and algorithm are available for free to other scientists so they can assess physiological time in a person’s body. Northwestern has filed for a patent on the blood test.

0 views0 comments