Biphasic Sleep - Maybe We Don't Need 8 Hours Of Sleep Every Day?


Many people around the world experience sleep issues including lack of sleep, disturbed sleep and sleep disorders. Doctors all over the world suggest that you get a good 6-9 hours of sleep every night. This is such a common health tip that most people already know it.

Most people get all their sleep in one chunk of time, typically at night. This is called monophasic sleep, mono meaning “one”. In the modern world, it is hard to find a society or culture that doesn’t make use of monophasic sleep as the core sleeping habit.

However, some cultures do not subscribe to the monophasic format of sleeping. In many places, an afternoon nap or siesta is quite common on a daily basis, for example, in Spain. This type of sleep structure is called biphasic sleep, where the total sleep time is segmented into two (“bi”) parts.

Another word you might hear regarding sleeping patterns is polyphasic sleep, “ploy” meaning many. In polyphasic sleep, sleep is phased into more than 2 segments, usually 4 or more. We’ll take a look at polyphasic sleep along the way, for now, let’s dive into biphasic sleep:

What exactly is Biphasic Sleep?

Biphasic sleep is a pattern of sleep where a person gets their daily sleep in two parts or segments. Biphasic sleep can include two segments of similar lengths, such as 5 hours at night plus an additional 3 hours during the day. It may also be very similar to a monophasic sleeping pattern, with the majority of sleep time being achieved at night along with a 1-2 hour nap during the day.

Some people naturally end up with biphasic (or even polyphasic) sleep patterns, either due to preference, natural sleepiness, or routine. Other people intentionally try to develop a biphasic sleep pattern with the goal of having more awake time for productivity.

Does everyone who takes a nap during the day become a biphasic sleeper? If it’s only an occasional nap, that doesn’t really count as a sleeping ‘pattern’. If you take a nap every day, this can be considered biphasic sleep, especially if you do not sleep for a full 7-8 hours at night. Some people may be forced to use a biphasic sleep cycle due to the constraints of work (such as those working a night shift).

Polyphasic sleep patterns are even more extreme than biphasic sleep. Some formats call for just 4 segments of 30 minutes of sleep (a total of just 2 hours each day!). Other formats of polyphasic sleep also include a larger “core” sleep segment at night, which may be easier to get used to.

Are there any benefits of Biphasic Sleep?

There is a lot of historical data that biphasic sleep was actually the original sleeping pattern, at least in Europe. Certain studies and books have detailed the prevalence of ‘first’ and ‘second’ sleep in literature and history. It is thought that industrialization, electric lights and increased working hours during the Industrial Revolution enabled or even influenced monophasic sleep to become the dominant sleeping pattern.

The science behind the benefits of biphasic sleep is mixed, some say it can be a positive for productivity while others suggest it may contribute to sleep deprivation issues. In some studies, biphasic sleep won out against both monophasic and polyphasic sleep.

Short naps and even longer siestas were found to have some benefits, but they could also increase the risk of altered sleeping patterns. This in turn could lead to sleep deprivation and its associated risks (including obesity, heart disease, mental issues and diabetes).

It seems from most of these studies that there are certain benefits to taking a nap during the day, but if it affects your nighttime sleep it can cause negative effects. The question remains, is biphasic (or polyphasic sleep for that matter) even effective for better productivity? Unfortunately, since this is a niche topic, there is very little conclusive data to prove either side. It is unknown whether biphasic sleep actually increases productivity and alertness or causes damage and increases the risk of distrurbed sleeping patterns.

What is known, however, is that both biphasic sleep and polyphasic sleep give people the time/opportunity to be more productive. People with this extra “awake’ time may be able to perform more work and attempt other personal goals. But it could be harming their mental and physical health long term. Until there is a large-scale study comparing different sleeping patterns and the risks or benefits associated with each, we can’t really know.

Should you try it out?

As mentioned before, some people are already naturally in bi or polyphasic sleep cycles, despite how the majority of society sleeps. Some people with sleep disorders too, have polyphasic sleep, although this is usually not intentional and can cause other health issues. If you find yourself naturally gravitating to two segments of sleep each day, maybe you are already in a biphasic sleep cycle.

It is not advisable to attempt either biphasic or polyphasic sleep without informing your doctor and/or a close family member. You may experience irritation, loss of focus or a whole host of symptoms linked to irregular sleep. You may also gain some benefits without experiencing negative effects, but only if your body is naturally more inclined to these types of sleeping patterns. Remember, everyone already requires different amounts of sleep to feel rested and stay healthy. The same thing applies to your sleeping pattern as well. It may just be possible that grabbing a nap during the day is just what your body needs or just one long segment of sleep at night is what’s best for you. To reiterate, do not attempt any of this without consulting your doctor especially if you already have underlying medical issues.