The health pros and cons of sharing a bed with your dog

They are known as man’s best friend. But do dogs really make the best sleep companions?

The issue remains highly controversial, with about a  third of dog-owning Americans allowing their pooch to get into bed with them at night.

The mere thought of sharing a bed with a shedding dog repulses a similar share of people. 

Some anthropologists have speculated that the idea of dogs sleeping with humans is an ancient urge encoded in our DNA.

But others warn that co-sleeping with a pet is unhygienic or even hazardous to your health — disrupting your sleep and raising your risk of worms.

Experts at the Washington-based Sleep Foundation say sleeping with your dog is a ‘personal decision,’ and they have set out a list of pros and cons to help people make an informed decision.

Pro – comfort and security

Having a dog wrapped in bedsheets can boost feelings of security and protection, experts say.

In a 2018 study, researchers surveyed 962 American women — half of whom shared their bed with a dog — on how they felt while in bed.

Those who reported being with a dog reported higher feelings of protection compared to those sleeping with a cat, a partner, or alone.

Researchers suggested dogs may boost these feelings because they are seen as ‘guard animals’ and are well-known to protect owners.

They may also have gotten a dog in order to protect their home and deter crime.

Pro – reduced stress

Many studies showing how cuddling up to or stroking a dog can reduce someone’s stress levels.

Although few have been done in the bedroom, researchers say there is no reason why the calming effects of being with a dog don’t reach there.

Many studies show that simply petting a dog reduces cortisol levels — the human stress hormone. 

One study from 2017 looked at 10 female dog owners who interacted with their labradors for an hour, with blood samples taken before and after.

Measuring hormones, they found boosted levels of oxytocin — associated with stimulating social bonding, relaxation and trust — and lower levels of cortisol after the interaction.

Another study from the same year involved 101 children aged seven to 12 years old who were left with a dog, alone, or with a parent.

Results showed that those with a dog had a buffered stress response compared to children who were alone or with their parents.

Experts at the Sleep Foundation said: ‘Most of the studies conducted on the mental health benefits of having a pet were conducted when participants were awake, so it is unclear whether these benefits apply when people sleep with their pets.

But they added: ‘If sleeping with dogs involves snuggling up and making direct physical contact, it might result in less stress and increased relaxation.’

Pro – boosted immunity

Many adults order dogs out of the bedroom for fear of the germs, parasites and worms they could bring in.

But experts at the Sleep Foundation say that exposure to germs can benefit the human immune system — especially at a young age.

Sharing a bed with your dog exposes you to a wider variety of germs. But it can also raise the risk of a serious infection or catching worms.

Coming into contact with a wide variety of germs early in life programs immune cells to recognize which are dangerous and which are not — boosting protection and reducing the risk of misfires that trigger allergies.

The Sleep Foundation says: ‘Researchers hypothesize that exposure to a diversity of microorganisms benefits human health and immunity, while a lack of diversity might be to blame for a rise in allergies and autoimmune disorders.

‘Past research shows that petting a dog increases an immune response, so the close contact of sharing a sleeping space may benefit the immune system more than simply having a dog in the house.’

Previous research has shown that living with a cat during the first year of life reduces the risk of developing allergies by age 18.

The costs of poor exposure to microorganisms early in life are coming to light this year, in the wake of successive lockdowns.

Children have faced outbreaks of common illnesses including flu and RSV — after stay-at-home orders robbed them of contact with these early in life, and how to protect against them.

Pro – lower blood pressure

There is a growing body of research showing owning a dog can reduce your blood pressure and improve cardiovascular health, benefits that experts suggest can be extended to the bedroom.

They cite a study from 1988 that found that simply petting a dog or talking to one triggered a reduction in blood pressure among participants.

And a University of Missouri study from 2004 found that human blood pressure dropped by ten percent after just 15 to 30 minutes of petting a dog.

The Sleep Foundation suggests that just touching a dog before going to sleep could help someone reduce their blood pressure.

They write: ‘If touching your pet is part of the key to gaining health benefits, cuddling up together at night might help.’

Experts at Harvard University add, on the general benefits dogs have on blood pressure: ‘Several studies have shown that dog owners have lower blood pressure than non-owners — probably because their pets have a calming effect on them and because dog owners tend to get more exercise.

‘The power of touch also appears to be an important part of this “pet effect”. Several studies show that blood pressure goes down when a person pets a dog.’

Con – allergic reactions 

About 10 to 20 percent of Americans are allergic to cats and dogs, while nearly one in ten have an allergy to pollen.

Experts warn that sharing a bed with a dog raises the risk of suffering an allergic reaction, and that those with allergies should think twice before inviting a dog into the bedroom.

An allergy is when the immune system misfires and attacks a non-dangerous substance, triggering a reaction.

People with dog allergies are responding to dander from dogs — dead skin cells in the air or collecting as dust —, as well as hair from the animals or saliva. Symptoms include a runny nose, sneezing or wheezing after petting a dog.

The animals can also carry allergens like pollen into the bedroom in their coats, again triggering an allergic reaction in owners.

The Sleep Foundation says: ‘Although exposure to pets in infancy makes a person less likely to develop pet allergies, research suggests that having a pet for the first time in adulthood may make a person more sensitive to pet allergens.

‘Having a cat for the first time in adulthood was also found to be more associated with eczema, an allergy-related skin condition.’

The best way to avoid an allergy to a pet is to ensure that you are exposed to the animal early in childhood, they said.

This helps the immune system recognize that dander from the animal is not a threat, and as a result not trigger an immune reaction.

People are twice as likely to be allergic to cats compared to dogs, likely because the animals are regularly washing themselves.

Con – infections 

While exposure to germs from pets can strengthen the immune system, researchers warn that it also runs the risk of serious infection.

Sharing your bed with a dog can lead to them passing on diseases and parasites to you, possibly via licking, feces, or from their fur.

In 2017, more than 100 Americans became infected with the ‘puppy-cuddling disease’ Campylobacter after petting their dogs. Five were hospitalized with symptoms including severe diarrhea, vomiting, and cramping.

Last year a mother-of-three was hospitalized for three days after she contracted a stomach bug when her pet chihuahua decided to defecate in her mouth as she slept.

Infections can travel the other way too, with an Italian greyhound belonging to a gay couple in Paris being diagnosed with monkeypox last year. Several dogs also became infected with Covid.

There are also concerns that a pet dog could transfer parasitic worms to their owners should they share the same bed.

Dogs pick up these worms while snuffling around in the dirt or swallowing feces infected with eggs or larvae from the worms.

The Centers for Disease Control and Prevention (CDC) warns they can then pass these on to humans via contact with feces, which can happen in the bedroom. They add that eggs from the worm can survive in dirt for years.

The Sleep Foundation says: ‘On the one hand, exposure to a greater variety of bacteria and other microbes may help strengthen the human immune system.

‘On the other hand, pets can bring harmful bacteria, viruses and parasites into the bedroom, putting the families they live with at risk for zoonotic diseases.’

To minimize the risk of infection in bed, they say dog owners should wash their sheets and bedding regularly. 

They say that pet owners should not allow their dogs to lick or kiss their face, as this raises their risk of infection.

Con – disrupted sleep 

Many people say that sharing a bed with their dog helps them feel comfortable or more secure when they get shut-eye, with seven in ten saying they feel as though their sleep is improved.

But the animals can also disrupt someone’s sleep, and lead them to wake up several times during the night.

A 2018 study involving nearly 1,000 people found that pet owners experienced lower sleep quality.

Another paper from 2017 looked at sleeping with dogs in beds compared to other places in the bedroom.

Involving 40 adults with sleep disorders, they found human sleep efficiency was lower when dogs were in the bed compared to when they were not.

The Sleep Foundation said: ‘The sleep quality ramifications of sharing a bed with your dog are likely relatively mild.

‘However, if you would like to minimize sleep disturbances, researchers have found that having the dog sleep elsewhere in the bedroom does not impact sleep to the same extent.’

Humans need to get about eight hours of sleep every night, but more than a third of American adults fail to get more than seven hours a night on a regular basis.

Reasons for failing to get enough sleep include stress from work, late bedtimes, and lifestyle choices such as smoking or drinking coffee in the afternoon.

Con – aggression

Your bedmate may be soft and cuddly, but experts warn that if startled they could accidentally bite someone.

A study on sleeping with dogs involving more than 1,000 people in Jamaica and San Francisco found dogs sleeping in a person’s bedroom were more than twice as likely to bite someone compared to those that were not in Jamaica. 

No such link was seen, however, for the dogs in San Francisco.

Another study warned that about six percent of all dog bites occurred when a dog was sleeping or resting immediately before the bite.

The Sleep Foundation says: ‘Children are more likely than adults to sustain a dog bite requiring medical attention.

‘This trend could be because they are not as good at reading signs of fear or aggression, or because they are more likely to get very close to a dog’s face.’

They add: ‘This is not to say that children can never sleep with a dog, but parents might not want to allow children to sleep with dogs that have shown aggression before.’