It can take the body up to 2 days to get rid of all the caffeine you drink in a couple of energy drinks. Each energy drink contains around 200 mg of caffeine. Caffeine has a half life of 6 hours. Let's do the math:

• You drink 2 energy drinks on afternoon (say around 3 o'clock). That's 400 mg of caffeine.
• At 9 PM, you still have 200 mg in your system - enough to keep you wide awake.
• By 3 AM, you have 100 mg still in your body - that's the amount in an average cup of coffee. If you have slept at all, it hasn't been good quality sleep.
• By 9 AM the next day, your body has 50 mg of caffeine still (assuming you haven't had any coffee in the morning). That's just under the amount found in 2 cakes of soda.

In short - energy drinks just have too much caffeine. There is no way to drink them and not have your sleep quality impacted.

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