Circadian Rhythm

Circadian Rhythm is the regular recurrence, in cycles of about 24 hours, of biological processes or activities, such as sensitivity to drugs and stimuli, hormone secretion, sleeping, feeding, etc. This rhythm seems to be set by a 'biological clock' which seems to be set by recurring daylight and darkness.

How Does the Suprachiasmatic Nucleus (SCN) Control Circadian Rhythm?

Circadian rhythms are biological cycles within organisms that allow them to adjust their physiology and behavior to anticipate and adapt to changes in the outside environment. Circadian rhythms are maintained with the help of circadian clocks, the main circadian clock in mammals is the suprachiasmatic nucleus (SCN).

What is the Circadian Rhythm?

Circadian Rhythm and Weight Loss

Artificial Light Exposure and Circadian Rhythm

Circadian Rhythm Length Variations - Early Birds and Night Owls

Circadian Rhythm Sleep Disorders

Social Jetlag and Sleep

How Does Airplane Travel Affect the Human Body?

The Circadian Rhythm and the Immune System

Memory Recall and Circadian Rhythm

Chronobiology: Why Time Matters in Medicine

Latest Circadian Rhythm News and Research

Study shows polar winter challenges men’s muscle mass but not hormone levels

Researchers tracked testosterone, cortisol, and body composition in 23 men overwintering at Concordia Station, Antarctica. Despite extreme polar conditions, hormone levels remained stable, though nearly half the crew experienced significant muscle loss.

26 Jun 2025

Disrupted biological rhythms in teens can produce unexpected brain effects

A new McGill University-led study suggests that disrupting the body's internal clock during adolescence can alter how the brain responds to an in-utero risk factor linked to certain brain disorders.

17 Jun 2025

Short peptides show promise in blocking breast cancer metastasis

A surgeon can excise breast cancer from the body, but even the most skilled scalpel may not be able to remove every cell - especially when the cells have spread from the original disease site elsewhere in the body.

13 Jun 2025

Sleep disorders predict dementia risk years before diagnosis, study shows

Researchers analyzed health records from over 1 million people in Finland, Wales, and the UK to assess the long-term impact of sleep disorders on neurodegenerative diseases. They found that diagnosed sleep disorders can predict Alzheimer’s, Parkinson’s, and dementia risk up to 15 years before symptoms, regardless of genetic predisposition.

28 May 2025

Researchers uncover link between heart attack severity and circadian rhythm

The molecular mechanism behind why heart attacks can vary in severity depending on the time of day has been uncovered by researchers at UTHealth Houston, potentially paving the way for innovative treatments that align with the natural circadian rhythm.

23 Apr 2025

Interferon regulatory factor 8 identified as key driver of liver fat buildup in NAFLD

Non-alcoholic fatty liver disease (NAFLD) is a hepatic metabolic syndrome resulting from lipid metabolic imbalance. Interferon regulatory factor 8 (IRF8) is well known for its roles in immune cell differentiation and tumor pathogenesis; however, its role in regulating glucose homeostasis and lipid metabolism remains unclear.

22 Apr 2025

Daytime eating shields night shift workers from heart risks

Researchers examine how daytime eating may preserve cardiovascular health among night shift workers.

14 Apr 2025

Your phone might be the reason you can’t sleep

Researchers investigate whether screen use in bed, particularly social media use, affects sleep as compared to other screen-based activities in students.

4 Apr 2025

Nighttime screen use linked to poorer sleep quality and shorter duration

Researchers examine how electronic screen use before bed affects sleep among adults.

2 Apr 2025

Circadian rhythms play a crucial role of in regulating tumor progression

Circadian rhythms are endogenous time-keeping mechanisms that regulate physiological processes in response to external light-dark cycles.

21 Mar 2025

Daytime sleepiness may double dementia risk in elderly women

For women in their 80s, experiencing increasing sleepiness during the day over a five-year period is associated with double the risk of developing dementia during that time, according to a study published on March 19, 2025, online in Neurology®, the medical journal of the American Academy of Neurology.

20 Mar 2025

Polluted soil and water are fueling a global heart disease epidemic

A new study in Atherosclerosis shows that soil and water pollution, including microplastics and toxic chemicals, significantly raise cardiovascular disease risks. The research highlights how emerging contaminants and poor environmental practices drive global health threats.

16 Mar 2025

Circadian clocks influence muscle recovery

The body's internal clock doesn't just dictate when we sleep - it also determines how quickly our muscles heal.

6 Mar 2025

Internal body clock influences eating habits of obese teens

Researchers found that teens with obesity ate more later in the day than their peers of healthy weight, and that their eating behaviors were strongly influenced by their internal body clock.

17 Feb 2025

Boosting BCL6 may counteract muscle loss from GLP-1 medications

About one in eight adults in the United States has tried or currently uses a GLP-1 medication, and a quarter of those users cite weight loss as their main goal.

23 Jan 2025

Innovative research links biometric data to mood prediction in shift workers

The CORONA virus pandemic also brought about a pandemic of mental illness. Approximately one billion people worldwide suffer from various psychiatric conditions. Korea is one of more serious cases, with approximately 1.8 million patients exhibiting depression and anxiety disorders, and the total number of patients with clinical mental diseases has increased by 37% in five years to approximately 4.65 million.

22 Jan 2025

Monoamine neurotransmitters emerge as architects of brain physiology

A collaborative effort between Mount Sinai and Memorial Sloan Kettering Cancer Center has shed valuable light on how monoamine neurotransmitters such as serotonin, dopamine, and now histamine help regulate brain physiology and behavior through chemical bonding of these monoamines to histone proteins, the core DNA-packaging proteins of our cells.

9 Jan 2025