Coffee Naps and the Science Behind Them

Caffeine is the most widely used psychoactive drug in the world. A cup of coffee in the morning is the ideal pick-me-up for most individuals. However, drinking coffee before a nap may seem counterintuitive. A coffee nap involves taking an immediate 20-minute nap after downing a cup of coffee. To know how this works, we have to take a look into the chemistry of sleep.

Adenosine is an inhibitory neurotransmitter in the brain. When it binds to its receptor, it acts as a nervous system depressant, making us sleepy. Caffeine acts as an adenosine receptor antagonist, causing an opposing effect to adenosine. In the brain, caffeine competes with adenosine to bind to the same receptors. This does not exterminate adenosine but instead prevents it from getting received by the brain, making us feel less sleepy. 

After drinking a cup of coffee, it takes a while for the caffeine to have its effect. The caffeine needs to go into the small intestine, pass into the bloodstream and enter the brain; this takes around 20 minutes. 

How To Take Advantage of Coffee Naps

1) Energy boost

A coffee nap involves drinking coffee just before one catches forty winks. It is thought to boost energy levels by increasing the brain’s capacity to receive caffeine. Sleep decreases adenosine and thus frees up the receptors in the brain to receive caffeine. That’s why a coffee nap may increase energy levels more than just drinking coffee or sleeping alone.

2) Amount of coffee to ingest

The amount of coffee ingested influences the effectiveness of coffee naps.  Drinking two cups of coffee (about 200mg) before napping for around 20 minutes seems to be the best way of reaping the benefits of coffee naps.

3) Duration of coffee naps

Sleeping for more than 30 minutes may cause us to fall into a type of deep sleep called slow-wave sleep. Studies have shown that waking up from a slow-waved sleep could cause sleep inertia which is a state of drowsiness and disorientation. Thus, coffee naps of less than 30 minutes are ideal as they may prevent this.

4) Time of day for coffee naps

Studies have shown that drinking coffee – around 400mg or four cups, just before bed causes disrupted sleep at night. Thus, it has been suggested that taking coffee naps at least six hours before bedtime is the most effective way of preventing disturbed sleep.

The study of coffee naps is still in its infancy; more research needs to be done to find out the effects of added sugar and flavour on coffee naps, if there are any. Moreover, excessive caffeine intake can result in anxiety, restlessness, muscle tremors and other conditions in some people. Most health experts agree that up to 400mg or four cups of coffee a day is safe for most people.

Although research is limited in supporting the effectiveness of coffee naps in increasing energy levels, compared to either drinking coffee or sleeping alone, coffee naps are certainly worth a try, as long as we don’t go overboard with our coffee consumption.

Written by Katharine Tay Xin Yi