How To Clean Pillows

Unless you want to regularly throw away your pillows and buy new ones, knowing how to clean pillows is an important piece of information.  The first step towards this is known what type of pillow you have, as different types of pillows have different cleaning methods.  Here are some tips for the most popular types.

Down and fibre filled pillows

Clean pillowWith both down and fibre filled pillows, most of them can be washed in the washing machine.  The pillow itself will have a label telling you exactly what temperature and type of wash can be used for the best results but if for some reason the tag is no longer legible, then the best bet is to go for a gentle cycle.   Either put two pillows in at a time to keep the washer balanced or using a front or top-loading machine without an agitator.  If you only have a washer with an agitator, then load the pillows in vertically to reduce the change of them being wrapped around it and damaged.

As well as using a gentle wash, it is also a good idea to use an extra-cold rinse and an extra spin.  If you tumble dry pillows, do it on a low heat and fluff and turn them frequently.  Good Homekeeping’s Research Institute also recommend adding a couple of rubber dryer balls to help maintain the pillows fluffiness and stop it clumping up when drying.

Foam pillows

Foam pillows can’t be washed in the washing machine because the heat will ruin them.  However many have a removable cover and this will be washable as per the instructions on the label.  A good way to freshen up a foam pillow is to give it a good vacuum using an upholstery tool.  Dial the suction level down a bit if needed so you aren’t fighting with the pillow vanishing up the tube.  Another option is if you have a no heat or air-only cycle on a tumble dryer, then you can put the pillow in this for around 20 minutes to freshen it up.  You can use spot cleaner on areas or bathe it with a damp cloth then leave to air dry before putting it back on the bed.

Some foam pillows have instructions for hand washing and if this is the case, make sure you do it very gently.  Wet foam can rip easily so cleaning gently is important.  If your pillow doesn’t have a liner, then consider getting one as this considerably lengthens the life of the pillow.

Decorative pillows

Bed pillows aren’t the only ones that can need a freshen up – decorative pillows from the living room can easily get stained and dirty.  Again, reading the label is the first step because everything should have instructions on it as to whether you can machine wash it or not.  With many of the colourful and patterned outer pillowcases, these will require hand washing due to the delicate or fancy nature of the materials used.  Hand washing also allows you to make sure there is no damage caused to embellishments or frills that might otherwise be caught up in a washer and could be ruined.

The actual pillow itself will be washable in the same way as a bed pillow, dependant on the type of filler used.

Bed bugs

Everyone dreads discovering they have an infestation of bed bugs but unfortunately the horrible little menaces are on the rise, no matter how clean and tidy you are.  Therefore it never hurts to know what to do to kill them should the worst happen and you find you have the most unpleasant house guests.

Pillows are one of the favourite havens of bed bugs but their presence can be spotted quite easily.  Look for tiny dark spots that are bug droppings as well as a sweet, musty scent that marks their presence.  Getting the pillows and bedding into the washing machine is the first step, usually on as hot a wash as possible without damaging them.  But don’t forget, these little devils also hide in the mattress and other crevices so make sure you put a comprehensive clean-out into place to avoid them moving back into the pillows when you return them to the bed.

What is Sleep Hypnosis?

Hypnosis, often called hypnotherapy, is a natural treatment that can have benefits for those suffering with a sleep disorder.  There are millions of Americans who have some form of a sleep disorder every year and the use of sleep hypnosis is showing signs of potentially being a benefit to them.


Of all the sleep disorders, insomnia is the most common, with around 30-40% of people thought to suffer from it at some stage each year.  There are two main types; temporary or transient and permanent or chronic.

Temporary insomnia usually lasts anywhere from one night to three or four weeks.  There is a variety of different triggers such as jet lag, stress, change of working conditions, alteration of sleeping patterns, noises such as snoring, room temperature or what you eat or drink before bed.  If the condition returns over a number of months for periods of time, it is classified as intermittent.

Chronic insomnia lasts for at least one month and occurs nearly every night.  It can be brought on by medical conditions such as arthritis, Parkinson’s disease, asthma and even allergies.  It can also be caused by the pain created by a medical condition or as a side effect of the drugs to treat them.  Other causes include depression, stress, anxiety and changes in the body’s hormones.

How it works

hypnotist-29832_1280Hypnosis is a state similar to a trance when the individual is deeply relaxed, their attention focused and they are more open to suggestion.  Due to this suggestibility, hypnosis is often used to help alter behaviours and reactions that may be causing chronic health problems such as insomnia and sleep disorders.

While treatment by a hypnotherapist is common, there are also self-hypnosis techniques that are often used by insomniacs.  It is suggested that it may be helpful in reducing anxiety by moving the mind away from the source of the anxiety and bringing about relaxation.

Sleep hypnosis as a treatment is often paired with sleep hygiene instructions for the best impact.  Researchers have also found that the treatment may work well for people suffering with nightmares, sleep terrors, sleep walking and even bed-wetting.


One example was someone suffering from insomnia where anxiety was acting as a barrier to her sleeping.  When she was anxious, her adrenaline levels were high and this meant she couldn’t fall asleep.  Visual imagery and the sense of touch were used by hypnotherapists to help her learn techniques to create a comfort zone and triggering good feelings.  This taught her to relax and was then able to fall asleep, while during the day the same technique helped her remained focused and alert in what she was doing.

One hypnotherapist described the process as like being at the cinema – you become involved in the movie and enjoy the story, even jumping at the scary bits no matter how predictable.  You don’t over think the matter and start thinking about the actors and the quality of the sound crew, you simply involve yourself in the film.  Hypnotism can work a little like this – you are in a susceptible state where you can change the patterns in yourself instead of over thinking about things.  You can stop something making you anxious instead of dwelling over what it is.

What Is Goose Down?

When shopping for a pillow, one has many options to consider.  For those who desire a soft pillow, goose down pillows are the way to go.  In this article we’ll talk about what you need to consider when choosing a goose down pillow.

What’s in the pillow?

Goose downJust what is down exactly?  Down feathers are the feathers found underneath the tougher exterior feathers of a bird.  Younger birds are covered in down feathers, as they have not had time to form tougher feathers.  Down feathers have a natural insulating property, and are used by birds for this reason.  Down feathers on birds contribute to helping them regulate their body temperature, and also to increase their buoyancy in water.

Because of their useful qualities, down feathers have been harvested and cultivated by humans for centuries.  In documents dating back to the 1600’s Russian merchants were recorded as selling “bird down” for the purposes of insulation.  As the years have gone on, they have become used in everything from jackets to sleeping bags.  The latest iteration of down products are down pillows.  Down is harvested in a variety of ways, but the most common way it is harvested is by removing the feathers from the bird post mortem.  Often times the feathers are removed from the birds while they are living, which has been denounced by animal welfare groups.  Check with the manufacturer of the product you are using to see how the feathers are collected before purchasing.

Why choose goose down?

So after all this, why is goose down a good filling for a pillow?  There are a variety of reasons.  To begin with, goose down pillows are extra lightweight, and extremely soft.  For people who enjoy a softer pillow and less firm, a goose down pillow is perfect.  Also, because they pack down easily, they make the perfect pillow for travellers and those who move around a lot.  They are also very quiet, so moving around at night won’t wake you or your significant other.  While there are a lot of plusses, however, there are also a lot of minuses.  For starters, goose down is very insulating.  It retains heat well.  This can be good for cold winters, but for those who like a cool pillow, it can be miserable in the summer.  Because goose down pillows are so soft, they don’t offer a whole lot of loft or support.  Those with back or neck problems will not fare well with them.  Goose down pillows also slowly lose their plumage, meaning they won’t last forever.  Coupled with their pricey initial cost, this can be a no-go for people on a budget.

When looking for down pillows, look to see what the pillow’s stuffing content is.  Products labeled as “100% goose down” will include only goose down, and nothing else.  These are the most packable pillows, but also the least supportive.  Products labeled as “goose down” generally contain around 90% goose down, and 10% other feathers.  These products will have more supportive regular feathers in the mix, that will give a little more loft to the final product.  Pillows labeled as simply “down” will be a mix of both feathers and fibers.

What are Euro Pillows?

Euro pillows are a type of pillow also known as a Euro or European sham pillow and are typically larger than the normal types of pillow.  They are used mostly as decorative pillows that are added to the bed then removed before sleeping.

Pillow sizes

Normally, pillows come in three sizes in most bedding sets; standard, queen and king.  The standard pillow is 20 x 26inches, the queen is 20 x 30inches and the king is 20 x 36 inches, making them all rectangular.  Euro pillows are square in shape and typically measure around 26 x 26 inches so are often referred to as square pillows.

How to use Euro pillows

Euro pillowsLike any decorative element, there are plenty of different ways to use them only limited by your imagination and your space.  However, here are a few ideas of how to arrange Euro pillows to get the best from them.

One idea is to use around five different pillows and stand them in front of the headboard.  Typically, the largest ones will be at the back, with rectangular ones in the middle and smaller Euro pillows at the front.  Often the back pillows will be plain in colour with the front two rows being patterned or coloured in keeping with the room décor.

If you don’t want to keep moving the pillows you sleep on, you could do a standing and stacked mix.  This would mean leaving your sleeping pillows in their normal place then standing some decorative pillows in front of them.  A typical arrangement may be three Euro pillows with a single, long and narrow decorative pillow, called a rolled pillow, at the front.

Another use of Euro and rolled pillows is to have a pair of rolled pillows at the back of the display, your sleeping pillows next, two or three Euro pillows then another rolled pillow at the front.  By having a single patterned Euro pillow behind a plain rolled pillow then white normal pillows behind this can highlight the colour or pattern you have chosen.

Of course, there doesn’t have to be order and function to the design; take a load of coordinating pillow and throw them on the bed for a random look that will be different every day.  Aim to have the most colourful pillow near the centre of the pile to bring out the match to your décor and don’t have too many patterns going on to avoid losing the impact of any one variation.


Usually, people choose not to sleep on Euro pillows and use them as a decorative piece.  This may because often the pillowcases provided with them tend to be more decorative and not so much the comfort option.  However, there is no reason that a Euro pillow can’t be used as a sleeping pillow just as easily.  Plain pillowcases are available in their specific size and, if nothing else, you could always turn your hand to a little sewing and make yourself some bespoke covers for them.

Toddler Pillows

Many of us take for granted our favourite pillow as an aid to getting the best night’s sleep and not waking with a sore neck.  The same will be true of your child when they reach a certain age and at this point, you should buy them a toddler pillow.

What is a toddler pillow?

Toddler PillowA toddler pillow is a special pillow designed for use by children as their first pillow.  It is the step up from the flat crib or other type of bed they have used up until now and a transition towards the normal pillows that they will use the rest of their lives.  They are specifically designed to have a low profile, be small and unobtrusive so that they provide support for the child without getting in the way.

As well as to start getting them used to adult ways of sleeping, some paediatricians recommend toddler pillows for some children.  This is most true for those that suffer with chronic ear infections or allergies as well as children that are prone to catching colds.

When to use

Children will have a different point when the introduction of a pillow is the right time for them along with other sleep related milestones such as using a blanket or not having a nighttime feed.  However, there are a few signs to watch for that may indicate that they are ready to give it a try.  These include being restless at night, particularly if they look as if their head position is causing them discomfort.  If they can move around in their sleep and keep their face open by repositioning, then they many also be ready to try a pillow.

Generally, most parents find that these signs start to occur when the child is around 18-24 months old, around the same time they are moved from a crib to a toddler bed.  Of course, like everything, each and every child will be different.

Make up of the pillow

There are similar considerations in selecting a toddler pillow as there are when picking a maternity pillow and they are different for each person.  Sometimes it can be a matter of trial and error.  However, some of the more common considerations are material and size.

When looking at the material that makes up the pillow, consider how soft it firstly as their gentle skin will be pressed against it.  If your child has shown any signs of allergies, make sure nothing in the material will aggravate the allergy.  Also, look to see if it is washable, as accidents are bound to happen.  The most common material is 100% cotton, either organic or non-organic.  The organic version will have no harmful toxins in, will not have used any bleaches in the manufacture and will not give off any gasses or dyes.

Toddler pillows tend to range in size from 12 inches to 18 inches so make sure you select one that fits inside their crib or bed.  Height is usually around an inch or two so they have a slightly elevated head but not too much and are a little like airline pillows.

What is a Home Sleep Study?

If a medical professional thinks you may be suffering from a sleep disorder such as sleep apnea then they will often suggest a sleep study to diagnose exactly what the problem is.  Sometimes this can be done in a sleep lab when a device called a polysomnograph (PSG) records information but it can also be done at home and this is what a home sleep study is.

Why stay at home?

There are some clear benefits as to why a home sleep study may be more beneficial and give better results than one in a lab.  First is the most obvious; people respond better in their own home and their own bed whereas when staying somewhere unfamiliar, this can alter sleep patterns and skew the test results.

Home sleep studies are also ideal for people who are house bound, elderly or have other chronic illnesses that mean they need the care of a family member or a nurse.  It is also ideal for people who work unusual shift patterns that means attending a sleep lab is difficult.

It also works out much cheaper to do the study at home without having any effect on the results of the test.

What happens in the study

The main areas that are studied are the oxygen saturation, heart rate, airflow and effort as well as snoring and sleeping positions.  The only things that are done extra in a lab is monitoring brain waves and leg movements.

Usually you can simply collect the device from a scheduled location rather than someone needing to visit the home and is a light and easy to carry device.  The common form of the device works by putting a belt around your midsection and attaching a clip on your finger.  An airflow sensor goes under your nose and you are ready to turn the machine on.

What kind of conditions are diagnosed?

Sleep apneaOne of the most common conditions that is diagnosed by this type of study is sleep apnea.  It is diagnosed across three levels of severity, which are

  • Mild – 5-14 episodes in an hour
  • Moderate – 15-30 episodes in an hour
  • Severe – more than 30 episodes in an hour

Sleep apnea is a disorder where patients have pauses in breathing or episodes of shallow or infrequent breathing.  Every time breathing pauses, this is called an apnea and can last anywhere from ten seconds to several minutes and can occur from five to 30 times an hour.  A shallow breathing event is called a hypopnea.

There are two main types of sleep apnea; central and obstructive, though people can have a combination of the two.  In CSA, breathing is interrupted due to a lack of respiratory effort while in OSA, this is because of a physical block to airflow despite respiratory effort and snoring is common in these cases.  It is thought that around 12 million Americans have OSA and there may be many more cases where people don’t realise they have the condition and it goes unreported.

Best Latex Mattresses

Latex mattresses have gone through something of a renaissance lately.  Today’s latex mattresses are made through much more environmentally helpful means, and offer no health risk to users.  They offer many of the same benefits of popular memory foam mattresses, and then some.  The latex mattress has pluses and minuses just like any mattress, which we will discuss here.

Why Latex?

Latex MattressWhy should one pick a latex mattress?  What should one look for in a mattress in general?  Remember, the mattress you pick you will likely be stuck with for quite some time.  You want to choose a mattress that you will like and not grow tired of.  Advice commonly given sound silly at first: at the mattress store, lie on a mattress for 15 minutes.  While you will look silly, this will be the best way to get a good feel for what you will find comfortable.  Also, while comfort is good, a mattress that is healthy for your back should take primacy.  Mattresses that are in the more medium-firm area will be best for your spine.

There are a few varieties of mattresses on the market, all of which you should take under consideration.  Every mattress type has its pluses and minus, leaving it up to your situation and your preferences to decide.

  • Innerspring mattresses are the most common type of mattress found on the market.  They work via a network of steel coins that suspend the sleeping area.  They vary greatly on the type and number of coils in the mattress.  Some mattresses work via a combination of springs and other methods, such as memory foam.
  • Waterbeds use a self contained unit of water for suspension.  They can be either “free flow,” in which the water is contained in one large chamber, or “waveless,” in which the water is separated into different chambers to contain the shape of the mattress.  Waterbeds can vary from soft to very firm, depending on the water pressure within them.
  • Foam mattresses use foam to provide cushioning for the user.  The foam materials are typically latex, memory, or polyurethane foam.  The only major downside to foam mattresses is that they tend to retain a lot of heat, leading to a potentially sweaty night.
  • Gel mattresses use a layer of gel to provide comfort to the user.  They also retain less heat than foam mattresses, giving them the edge in the temperature control department.
  • Airbeds work in much the same way that water beds do, but contain air in the chambers instead of water.  They are also often covered with a felt or foam cover to add extra comfort to the package.  Airbeds often feature compressors that can change the firmness of the mattress with the push of a button.


Latex mattresses work in many of the same ways that memory foam mattresses work.  Latex mattresses can be made two different ways: synthetic and natural.  Synthetic mattresses are made via a chemical process, while natural latex is made through harvesting natural latex from rubber trees.  There are two main methods of manufacturing latex mattresses: the talalay process and dunlop process.  The talalay process involves pouring the molten latex onto a mold, aerating it, and then frozen quickly to prevent the formation of bubbles.  Finally it is heated, washed, and then dried.  In the dunlop process, the latex is simply poured onto a pattern and cooked.  This process is used less nowadays, as the talalay process has proven to produce higher quality results.  Lower priced latex mattresses will often be produced via the dunlop process.

Why choose a latex mattress over other mattresses?  What are the advantages of latex over other mattress materials?  Like memory foam, latex mattresses tend to be better for people who suffer from back problems.  They are firm but allow the natural shape of the user to sink into the bed.  With latex mattresses there is less overall risk of toxins reaching the air.  Also, unlike foam mattresses, they are more breathable and therefore comfortable in summer months.  They also last for a while, sometimes even up to twenty years!  The downside is while not quite as pricey as memory foam, latex mattresses tend to be a bit on the pricier side.

What is Hypopnea?

Hypopnea is a sleep disorder that is similar to apnoea but involves periods of overly shallow breathing or an abnormally low respiratory rate whereas apnoea is where breathing stops altogether.  Therefore hypopnea is less severe a condition than apnoea but can nevertheless be frightening for sufferers.  It can be that you have the condition and get a full night’s sleep but don’t feel rested because you didn’t get the right kind of sleep.


There are various causes of hypopnea including:

  • Physical problem such as nasal septum deformation or a congenital narrowness of the nasal meatus (nose canal)  and the gullet
  • Severe cases of tonsillitis and/or adenoiditis
  • Being overweight
  • Any neuromuscular disease or condition that means the respiratory muscles are weakened
  • Using sedatives or sleeping pills
  • Alcohol abuse
  • Smoking
  • The ageing process

Nasal septum deviation is where the nasal septum becomes displaced and around 80% of people that have this condition never realise it.  It can occur from an impact accident or a blow to the face or it can be something that happened as a child or during childbirth.  In itself, it causes difficulty in breathing and infections around the sinuses as well as hypopnea and apnoea.  As well as the poor sleep, people often experience repeated sneezing, nosebleeds and pain in the face along with an impaired ability to smell.


SleepinessThe most common symptom of hypopnea is that people are excessively sleepy due to the lack of proper sleep.  People with the condition also tend to have a loud, heavy snore that is broken up by choking sounds or loud snorts then short periods of silence when the air cannot get through to the lungs.  This period can be around 20 seconds or longer and can happen as often as every hour.

Other symptoms due to the condition can be depression, mood changes, forgetfulness, loss of concentration, lack of energy and nervousness.  However, these are not always found by suffers and not all people with these conditions have hypopnea.


The most direct consequence of sleep hypopnea is that the carbon dioxide in the blood increases and the oxygen levels decrease, relative to how serious the airway is obstructed.  Generally, this means that people have a disrupted sleep pattern leading to fatigue, lethargy, lack of concentration, being irritable and headaches in the morning.  Or in other words, they act like someone who is really tired.

There are two main types of hypopnea; central or obstructive.  With obstructive hypopnea, the airway is only partial closed but it is closed enough to cause the physical effects.

There is a hypopnea index (HI) used to decide the severity of the condition whereby the number of events during a sleep period are divided by the number of hours slept.  Another method to diagnose severity can be the Respiratory Disturbance Index, which is also used for sleep apnoea and other conditions, but take into account events that do not disturb sleep but may be part of the condition.


One of the main treatment for the condition is called continuous positive airway pressure (CPAP).  This is where the patient wears a mask that covers their nose and/or mouth and an air blower pushes air through the upper airway.  The amount of pressure used can be altered so that it maintains the oxygen levels in the blood.

Another treatment used is an oral appliance.  This is the preferred method of the American Academy of Sleep Medicine especially for those with mild to moderate versions of the condition.  It is also used where people cannot manage to have the mask fitted in the CPAP treatment.  Oral appliances are custom made by a dentist who has been trained in dental sleep medicine.

Mild versions of the condition can be treated on some occasions by lifestyle changes such as avoiding alcohol or stopping smoking.  Also, learning to avoid sleeping on your back can sometimes have a beneficial effect, as can losing weight if you are overweight.  The use of sedative has been found to help some people, as have hypnotics.

Finally, surgery is a last-resort treatment and is only used when the person has a problem in the upper airway.  It can involve removing an obstruction such as tonsils, adenoids or the uvula so is not a solution for everyone who suffers with the condition.

Delayed Sleep Phase Syndrome

Do you often have trouble getting to sleep at night?  Do you find yourself not able to fall asleep until the early hours of the morning?  Do you find yourself tired throughout the day and frustrated that you can’t get enough sleep?  If so, it’s possible you have Delayed Sleep Phase Syndrome.  But don’t fear, as treatment is possible.

Circadian rhythm

Sleep disorderA Circadian rhythm is a natural biological process that sets the body’s functions on a 24-hour cycle.  These rhythms are driven by one’s circadian clock.  Circadian rhythm sleep disorders are family of sleep disorders characterized by the disrupting of normal sleep patterns and the circadian clock.  Those suffering from circadian rhythm sleep disorders are unable to function in a sleep pattern conducive to work and normal life.  Most unusually, most are able to get a good and uninterrupted sleep once they actually fall asleep.  These disorders are extremely harmful to those who suffer from them, affecting them biologically and also socially.  There are two different types of circadian sleep disorders: extrinsic and intrinsic.  One of the more common intrinsic circadian rhythm sleep disorders is Delayed Sleep Phase Syndrome.

Just what is Delayed Sleep Phase Syndrome?  Delayed Sleep Phase Syndrome is a circadian rhythm sleep disorder characterized in its most simple terms as the inability to fall asleep in a timely manner.  People who suffer from DSPS will often find themselves not falling asleep until early in the morning, and then having a hard time waking up in time for work or school.  Delayed Sleep Phase Syndrome affects almost .13% of the adult population.  For teenagers the numbers are much worse, with DSPS affecting almost 7% of teenagers.  DSPS especially affects people who are attempting to maintain a normal schedule.  Students or adults who work a 9 to 5 job will be most affected by DSPS as it inhibits them from blending into the normal daily routine.


What causes Delayed Sleep Phase Syndrome is not well known.  Because of its prevalence in adolescents, it is theorized that it may be an exaggerated form of the internal clock change that young people experience when undergoing puberty.  What we do know for certain about DSPS are the symptoms of it.  Symptoms of DSPS include the inability to wake up at the desired time, difficulty falling asleep until the desired time, a deep sleep once falling asleep, depression, and erratic behavior.  Because of these, the only way to properly diagnose DSPS is to analyze the subject’s sleep habits.  Because of its dramatic symptoms and similarity to other sleep disorders, it is often misdiagnosed.  An overnight sleep study, or a polysomnogram, will help eliminate the possibility of it being another sleep disorder.


Once DSPS is diagnosed, there are a few ways to treat the disorder.  The best and most simple way to fight back against DSPS is to start and maintain good sleep habits.  Maintaining a steady sleep schedule can be the best preventative against DSPS.  This may involve changing the current cycle of sleep, by moving back or forward they time one goes to bed.  A new method of treating DSPS is bright light therapy.  Bright light therapy consists of exposing the subject to a bright light for thirty minutes in the morning.  This helps reset the body’s internal clock.

There are also a variety of pharmaceutical treatments as well.  Consuming sleep medication may be a way to force oneself into sleep to create a sleep cycle.  Melatonin may be prescribed for this reason.  However, the problem with Melatonin is it has the potential to have drastic side effects that may outweigh the benefits of taking the drug in the first place.  Modafinil is a drug that is commonly prescribed for shift work sleep disorder, but can also be used for treating DSPS as well.

Finally, one of the least talked about treatments of DSPS is structuring one’s life around the disorder in a way that one can cope with the disorder.  This can involve taking on careers with late hours, or working at home in a way that allows one to work at their peak periods of energy.  It’s important to remember that it is never worth giving up, despite how much harder it may be for you.

Do Sharks Sleep?

Sharks are one of the most feared but least understood creatures in the sea today.  The subject of myths, legends, and movies, sharks are iconic as the great hunters of the sea.  Although they are fish, sharks have very unique biologies.  One of the most commonly asked questions about sharks is whether or not they sleep. Gills work by extracting oxygen from the surrounding water.  In order to do this, fish must constantly take in water into their gills.  This is called Ram ventilation.  While most fish have the ability to do this while sitting still, sharks do not.  Sharks evolved out their ability to take in water while sitting still.  Because of this, sharks are known as Obligate ram ventilators, meaning they must constantly swim to take in oxygen.

Unusual biology

SharkSharks have an unorthodox biology, even for fish.  Unlike traditional fish, sharks have no swim bladder.  Swim bladders provide buoyancy for fish, allowing them to float in place.  However, sharks to not have this, relying on the lift their fins provide in order to stay afloat.  If sharks stop moving, they will sink to the bottom.  Because of this, sharks are in a perpetual state of motion, constantly swimming.  Sharks rarely stop and nest on the ground.  But this isn’t only for buoyancy purposes.  While this may seem like a disadvantage at first, it actually holds many advantages for the sharks.  Because of a lack of swim bladder, sharks have the ability to dive to a variety of depths instead of being limited to just one as most fish are.  It allows sharks to be more mobile, coming and going as they please. In scientific studies of sharks, scientists noticed that sharks breathed more efficiently while swimming as opposed to resting on the ocean floor.  This keeps sharks swimming in an effort to gain more oxygen.  Counter intuitively, it is more energy efficient for sharks to continue moving than to simply rest.

Do Sharks Sleep?

This then poses the question, do sharks sleep?  For years it was hard to tell.  As sharks are constantly in motion, studying them to see if they sleep was a very difficult endeavor.  While it has never been proven definitively, small clues give us insight to the question.  Scientists studying small sharks have observed that the swimming motion of sharks is coordinated by the spinal cord, and not by the brain.  For this reason it is theorized that sharks sleep by continuing to swim with their spinal cord, and let their brain sleep. However, there are a few conflicting reports that throw a wrench into this hypothesis.  Water factors such as temperature, current, and salinity may affect sharks.  Reef sharks have been observed sleeping in caves in Mexico.  Discovery of the caves yielded dozens of sharks all dozing for the night.  Close inspection of the caves determined that the water in the caves had high oxygen levels, making it more energy efficient for the sharks to stay put than keep swimming. Great white sharks have observed the most unusual behavior recorded for shark sleep studies.  Geotagged Great White sharks have been observed in the Dyer Islands travelling to gullies at the bottom of the ocean and remaining stationary for hours.  The areas they have been observed doing this have currents passing through them, presumably bringing fresh ocean water into the sharks’ gills as they rest.  This would allow them to sleep while still getting enough oxygen. While the question hasn’t been settled for sure, it’s safe to presume that sharks to sleep to some degree.  What that looks like or if it even appears to be sleep at all is up for the verdict.