Will a coffee nap energize us?

April 21, 2017 / Biological Valley BIOON/-Coffee and naps seem to have something in common. They both wake us up and enhance our behavior, but some people think that having a cup of coffee before a nap may make us more energetic after waking up; is that really the case? Is there any research evidence to explain this "coffee break" (coffee naps)? And can we get a good night's sleep?

Sleepy?

If we don't get enough sleep, researchers define the condition as "sleep debt". Napping is a common way to overcome drowsiness and recover from sleep debt, while drinking coffee can help us spend the day. Since the 1990s, researchers have been studying how to combine naps and coffee to help improve human health.

In a study conducted in 1997, 12 insomniacs were asked to drink a large cup of coffee and then take a nap for 15 minutes, followed by some simulated driving tests to check their alertness. although eating coffee without a nap can also help improve the driving performance of participants, it is more likely to improve the performance of participants if combined with coffee nap Coffee nappers may be less likely to get off track during simulated driving than drinking coffee (not taking a nap) or decaffeinated coffee drinks (not taking a nap).

Coffee naps may improve participants' performance better if they take naps instead of deep sleep, and once participants get up, coffee naps can reduce their drowsiness and maintain alertness for hours. However, this early, small study also raised a number of questions. For example, we don't know how much coffee the participants consumed or whether they were prone to some caffeine shock.

The working principle of "coffee nap"

In order to understand the mechanism of this coffee nap, we need to explore how the body processes caffeine. When drinking coffee, caffeine stays in the stomach for a period of time before moving to the small intestine. Caffeine begins to be absorbed and dispersed throughout the body. It takes 45 minutes from drinking coffee to being absorbed by the body. But the wake-up effect of caffeine tends to occur earlier, about 30 minutes after drinking coffee, so drinking coffee within 15 minutes before a nap may not affect the body's sleep.

Once we wake up from a nap, we not only feel a "shock", but also often feel the effect of caffeine a few hours after drinking coffee; although caffeine is broken down in the liver, but after consuming a moderate level of caffeine, half of the caffeine stays in the bloodstream for 4-5 hours, and it often takes longer for the body to remove large amounts of caffeine from the body. When we wake up from sleep, the "shock" and "long tail effect" of caffeine tend to make us very energetic throughout the day.

How much coffee is safe to eat?

At present, there is a lot of research evidence that coffee nap can work, but is it safe? If we take into account caffeine consumption, 300-500mg of caffeine a day (2-3 large cups of coffee) seems to be safe, of which about 70% of caffeine is converted to paraxanthine, which has no significant toxic effect on the body. But consuming too much caffeine (more than 500mg a day) may cause symptoms such as nervousness, anxiety, irritability, restlessness and palpitations.

The Joint Food Standard (Food Standards Australia New Zealand) of New Zealand and Australia states that children between the ages of 5 and 12 consume 95mg caffeine every day, while adults who consume 210mg caffeine every day can increase their anxiety levels.

In fact, we tend to consume far more caffeine than the body needs, such as caffeinated drinks on supermarket shelves (Red Bull, etc.) and some drugs (Panadol Extra). We can monitor the body's caffeine intake by checking the amount of caffeine in common drinks, foods and drugs. If caffeine intake is excessive and we want to block caffeine intake, caffeine withdrawal tends to cause headaches, drowsiness and decreased alertness; therefore, caffeine use disorder is considered to be a disease that needs further study in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders, given the nature of caffeine addiction.

Is a coffee nap the best way to pay off your sleep debt?

When a coffee nap keeps us energized for hours, it may not be the best way to pay off our sleep debt; getting enough sleep on most days may be the best way to improve body alertness, performance and productivity, because sleep is important to a range of brain and body functions Getting enough sleep can significantly reduce an individual's risk of car accidents, weight gain, obesity, diabetes and depression. (biological Valley Bioon.com)

Reference:

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[15] Health Check: what are 'coffee naps' and can they help you power through the day?