For most people, eight hours of sleep is the holy grail of good sleep practices. It's something that we often aspire to but rarely ever achieve. 

But according to sleep researcher Dan Gartenberg, even eight hours is not enough.

Gartenberg, in an interview with Quartz, said that one should extend those rarely-achieved eight hours to half an hour more. 

The reason is that people often spend 10 per cent of their time either falling asleep or slowly waking up. Gartenberg explained,

If you're in bed for eight hours, a healthy sleeper might actually sleep for only about 7.2 hours.
Source: Huffpost

That's why, in order to get eight hours of 'actual' sleep, normal sleepers need eight and a half hours between when they close their eyes and when the alarm goes off.

But you don't really need to achieve the entire shut-eye time all at once. Gartenberg explained that if you get less than eight and a half hours worth of sleep, you can make it up by getting a power nap of 20-30 minutes at midday.

Source: Plan My Health

And giving in to the late afternoon sleepiness and grabbing a power nap might boost your productivity. Anyhow, it's way better than chugging cups of coffee.

In conclusion, you need to sleep for a total of eight and a half hours, be it in the night or in the middle of the day. Now if you'll excuse me, I'm gonna doze off for five hours now (damn you Netflix!)

GIFs have been sourced from Giphy.