Press Reset: The Science Behind Jet Lag 

We all know a certain amount about jet lag; the fatigue, the brain fog, the sleepless nights, and falling asleep in your dinner. It can make returning home from a holiday or work trip a real struggle. But what exactly causes jet lag, and how can you reset your body clock to bounce back faster? Let’s delve into the science behind it to discover how to recover and reset yourself for quality sleep faster.  

Understanding your body clock

Your body operates on a 24-hour internal clock known as the circadian rhythm. This biological timer regulates essential functions like sleep, hunger, hormone production, and even body temperature. It’s controlled by a tiny region in your brain called the suprachiasmatic nucleus which acts as the master conductor of your body’s daily rhythms.   

 The circadian rhythm is heavily influenced by external cues, primarily light and darkness. When your eyes detect light, they send signals to the SCN, which then tells your body whether it’s time to be awake or asleep. This delicate system works seamlessly—that is until you cross multiple time zones and throw it out of sync.   

How travel disrupts your circadian rhythm

When you travel across time zones, your internal cues can struggle to align with the local time. This mismatch between your internal clock and the external environment is what causes jet lag.

 Here’s what’s happening to your body:   

Melatonin production goes haywire   

Melatonin, often called the sleep hormone, is produced by the pineal gland in response to darkness. It helps you feel sleepy and prepares your body for rest. When you travel, the timing of light exposure changes, confusing your brain about when to release melatonin. This can leave you wide awake at night or sleepy during the day.   

Cortisol levels are disrupted

The ‘stress hormone,’ cortisol, also has a daily cycle. It progressively decreases during the day after reaching its high in the morning to aid in waking. This cycle is upset by jet lag, resulting in strange cortisol spikes. Because of this, you may experience excessive fatigue, agitation, or anxiety. 

Light exposure confuses your brain   

Light is the most powerful cue for resetting your circadian rhythm. When you’re exposed to light at unexpected times (e.g., bright sunlight late at night or darkness in the morning), it sends mixed signals to your brain, delaying your adjustment to the new time zone.   

Tips for resetting your internal clock

The good news is there are ways you can manage your jet lag to help you restore your sleep quality. By understanding the science, you can take proactive steps to reset your body clock and recover faster. 

Use light exposure strategically 

After travel seek bright light in the morning, (preferably natural light), to help your body adjust to an earlier schedule. Avoid strong light in the evening.  

Regulate melatonin production

Before you travel, talk to your GP about taking a melatonin supplement to support your recovery from jet lag. If it’s suitable for you, you can take melatonin in the hours before bedtime in your new time zone to help reinforce to your body that it’s time to sleep. Avoid screens (phones, laptops, TVs) before bed too, as blue light can suppress melatonin production.   

Adjust your schedule gradually

A few days before your trip, start shifting your sleep and meal times closer to the schedule of your destination. Once you arrive, stick to the local time immediately, even if you’re tired. This helps your body adapt faster.   

Stay hydrated and eat well   

Dehydration worsens jet lag symptoms, so drink plenty of water before, during, and after your travel. It’s also advisable to avoid heavy meals, caffeine, and alcohol close to bedtime, as they can disrupt sleep and confuse your body. 

Create a sleep-friendly environment 

A comfortable sleep environment can make a huge difference in helping your body recover. Use blackout curtains, or an eye mask to block out disruptions. 

Light exercise, like walking or yoga, can help regulate your circadian rhythm and reduce jet lag symptoms. Aim to exercise in the morning or early afternoon to boost alertness and avoid interfering with sleep.  

Jet lag is a sometimes unpleasant yet temporary disruption. Understanding the science behind it can help you take control of your recovery. By using light exposure, regulating melatonin, and prioritising high-quality sleep on a comfortable mattress, you can reset your body clock and return to your daily routine feeling refreshed, energised and inspired.