Circadian rhythm disruption and the effects of jet lag

Jet lag is a physiological phenomenon caused by the disruption of the body’s circadian rhythm, which is the internal clock regulated by light and dark cycles. This misalignment affects hormonal signaling, including the production of melatonin by the pineal gland, which typically encourages sleep during nighttime darkness.

Symptoms of jet lag can range from mild to debilitating and often include daytime fatigue, nighttime insomnia, diminished cognitive performance, and irritability. Because the circadian rhythm influences various organ systems and the immune system, travelers may also experience increased inflammation and gastrointestinal upset.