What we mean when we ask you to 'Avoid caffeine'

Avoid  caffeine entirely. Many beverages and even chocolate can contain some caffeine, so be sure to double check.

What will happen to my jet lag if I don’t avoid caffeine? 

If you use caffeine for longer than advised, you may find it more difficult to fall asleep at the right time, and you may have less deep sleep, making you feel more tired when you wake up.

I accidentally used caffeine. Now what?   

Don’t worry, the plan is not ruined! You may find it a bit more difficult to fall asleep tonight so make sure you follow all the pre-sleep advice. Going forward, make sure you know what does and does not contain caffeine. If you need a hot drink, choose a non-caffeinated herbal tea.

The Science

When we are awake, our cells use energy. A by-product of this energy use is an increase in the amount of adenosine in our bodies. Adenosine is part of the sleep regulation system, and is associated with increased sleepiness.

Caffeine is an adenosine-receptor antagonist and therefore blocks the sleepiness-inducing effects of adenosine. As a result, caffeine is a highly effective stimulant.

Caffeine stays in our system for a long time. It typically has a half-life of three to five hours so if you take 100mg of caffeine at 10am, you will still have 12.5mg of caffeine in your system at bedtime 12 hours later. Having caffeine in your body at bedtime will have a negative effect on your sleep that night. 

Using caffeine “little and often”, and then stopping it as long as possible before bed, will optimize the benefits of caffeine and minimize the negative effects on sleep.

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