What causes jet lag, and how is melatonin used to alleviate it?

SouravNovember 9, 2024

Answer

Jet lag is a temporary physiological condition that occurs when a person’s circadian rhythm is misaligned with the local time zone after traveling across multiple time zones. It leads to symptoms such as fatigue, sleep disturbances, irritability, and difficulty concentrating. The primary cause of jet lag is the disruption of the body’s internal clock, which regulates various biological processes based on the 24-hour day-night cycle.

Causes of Jet Lag

1. Circadian Rhythm Disruption:
   • The body has a natural circadian rhythm that dictates sleep-wake cycles, hormone release, and other physiological functions. When traveling across time zones, this rhythm becomes out of sync with the local day-night cycle, leading to jet lag symptoms.
2. Travel Fatigue:
   • Factors such as changes in cabin pressure, altitude, and dehydration during flights can exacerbate feelings of fatigue and discomfort associated with jet lag.
3. Direction of Travel:
   • Traveling eastward (losing time) is often more challenging than traveling westward (gaining time), as it typically requires advancing the body clock, which is harder for many people.

Role of Melatonin in Alleviating Jet Lag

Melatonin is a hormone produced by the pineal gland that helps regulate sleep-wake cycles and circadian rhythms. Its use in alleviating jet lag has been widely studied.

1. Melatonin Supplementation:
   • Melatonin supplements can help realign the body’s internal clock with the new time zone. Taking melatonin close to the target bedtime at the destination can reduce jet lag symptoms by promoting sleep onset and improving sleep quality.
2. Effective Dosage:
   • Research indicates that doses between 0.5 mg and 5 mg are effective for reducing jet lag, with higher doses (around 5 mg) potentially leading to faster sleep onset and better overall sleep quality. However, doses above 5 mg do not appear to provide additional benefits.
3. Timing of Administration:
   • For optimal results, melatonin should be taken shortly before bedtime at the destination (typically between 10 PM and midnight). This timing helps synchronize the circadian rhythm with the local environment.
4. Pre- and Post-Travel Use:
   • Some studies suggest that taking melatonin a few days before traveling and continuing for a few days after arrival can further enhance its effectiveness in mitigating jet lag symptoms