How cats and dogs can support human health: what science actually shows 🐾

We often say that pets make us happier.

But can cats and dogs really affect physical and mental health — reduce the risk of disease, support people living with chronic conditions, or even warn them about dangerous medical events?

There is a substantial body of research on this topic. However, the findings are much more interesting and complicated than the popular idea that “petting a cat lowers your blood pressure.”

Let’s look at where the health benefits of animals are genuinely supported by research, and where we still need to be cautious.

🔎 First, an important distinction

There is a major difference between an ordinary family pet, a specially trained assistance or service dog, and animal-assisted therapy — structured activities involving animals under professional supervision.

Research findings from one category cannot automatically be applied to another.

For example, a dog specifically trained to support a person with post-traumatic stress disorder is very different from an ordinary family dog.

Animals are not medication either.

They may help people cope with illness, improve quality of life or encourage behaviors that benefit health, but they do not replace doctors or evidence-based treatment.

🐶 Dogs can help us move more

This is probably the clearest mechanism to understand.

Dogs need walks. Not once a week when we feel motivated, but every day.

As a result, many dog owners naturally get additional physical activity as part of their daily routine.

Regular physical activity is a well-established factor in preventing many diseases.

Physical activity reduces the risk of:

• cardiovascular disease

• stroke

• type 2 diabetes

• excess weight gain

• some cancers

• dementia

• premature death

It can also help control blood pressure, blood glucose and body weight.

So the important chain looks like this:

dog → regular walks → more physical activity → lower risk of chronic disease.

It is therefore more accurate to say “living with a dog may encourage a person to be more active, and physical activity is proven to reduce the risk of type 2 diabetes” rather than “dogs prevent diabetes.”

❤️ Heart and cardiovascular health

The relationship between pet ownership and cardiovascular health has been studied for decades.

The American Heart Association has noted that pet ownership, particularly dog ownership, may be associated with more favorable levels of some cardiovascular risk factors.

Possible explanations include greater physical activity, social support and differences in the way people respond to stress.

Some meta-analyses have also found slightly lower average blood pressure and heart rate among pet owners.

Large analyses have found dog ownership to be associated with lower all-cause and cardiovascular mortality.

However, most of these studies are observational. That means researchers cannot prove that the dog itself caused the lower risk.

Dog owners may already differ from other people in their lifestyle, level of physical activity, social environment or other health-related factors.

Other studies have failed to find a clear protective association.

So it would be inaccurate to claim that simply owning a pet prevents heart attacks or strokes.

A much stronger conclusion is that dogs can encourage a more active lifestyle, which is independently beneficial for cardiovascular health.

🫶 Stress, loneliness and emotional wellbeing

For many people, an animal provides a consistent form of social contact.

You can pet them, talk to them, be greeted when you come home and experience the presence of another living being.

Research has linked interaction with pets to lower feelings of loneliness, emotional support and more opportunities for social interaction.

This matters because social isolation itself is associated with worse physical and mental health.

Strong social connections are linked with lower risks of depression, cardiovascular disease, stroke and dementia.

But again, caution is needed.

Studies examining ordinary pet ownership and clinical depression or anxiety have produced mixed results.

A cat or dog can therefore be an important source of emotional support, but it is not a treatment for clinical depression.

If someone needs psychological or psychiatric care, a pet should not be used as a substitute.

🧠 Animals and dementia

One particularly interesting area of research involves the use of animals with older adults living with dementia.

Here, researchers are usually studying organized animal-assisted interventions rather than simply owning a pet.

Systematic reviews have found that these interventions may improve social interaction, increase physical activity and, in some studies, reduce agitation and aggressive behavior.

More recent reviews and meta-analyses have also suggested possible reductions in some behavioral and psychological symptoms of dementia.

However, there is not strong evidence that interaction with dogs restores or substantially improves cognitive function.

Animals therefore do not “treat dementia.”

Instead, they may provide an additional way to make a person’s daily life calmer, more active and socially engaging.

🐕 Dogs and post-traumatic stress disorder

Specially trained dogs are also used to support people living with post-traumatic stress disorder, or PTSD.

These dogs may help a person feel safer, interrupt certain reactions, create physical space in public settings or assist during episodes of anxiety.

Systematic reviews have reported promising findings.

In some studies, people with PTSD who received a service dog or participated in animal-based programs experienced reductions in symptom severity.

However, studies vary in size and quality.

Service dogs are therefore considered a form of additional support rather than a replacement for psychotherapy or medication.

🩸 Dogs that detect changes in blood glucose

Some specially trained dogs can respond to changes in a person’s scent during hypoglycemia or hyperglycemia and alert their handler.

These dogs are sometimes used by people with type 1 diabetes.

However, research shows substantial differences in accuracy between individual dogs.

In some studies, sensitivity for detecting low blood glucose has been relatively limited, while other studies have reported more encouraging results.

Recent reviews also highlight the lack of standardized training methods and considerable variation in performance.

A diabetes alert dog may therefore provide an additional layer of safety, but it should never replace a blood glucose meter or continuous glucose monitoring system.

⚡ Dogs and epilepsy

Dogs are also used to support some people with epilepsy.

Some are trained to respond after a seizure begins.

They may alert another person, remain beside their handler or perform a specific trained action.

An even more fascinating question is whether dogs can detect an approaching seizure before it begins.

There are reports of such behavior, but high-quality scientific evidence remains limited.

The findings are promising, but they are not strong enough to consider a dog a reliable medical system for predicting seizures.

🐱 What about cats?

The situation is somewhat different for cats.

Most research on physical activity focuses on dogs — for an obvious reason: cats rarely insist that their owners go to the park at seven in the morning.

Still, cats can provide social contact and emotional support.

Research has linked interaction with cats with improved mood and emotional support, as well as additional opportunities for social connection for some older adults and people with disabilities.

Some observational studies have also found lower cardiovascular mortality among cat owners.

However, this does not prove that the cat itself has a protective effect.

A scientifically cautious conclusion is:

cats can be an important source of companionship, attachment and emotional support.

Claims such as “a cat’s purr heals bones,” “cats know exactly where the body is sick,” or “cats prevent heart attacks” are currently much closer to internet mythology than evidence-based medicine.

🌿 Can pets prevent allergies and asthma?

You may have heard that children who grow up with a cat or dog are less likely to develop allergies.

Scientists have studied this question extensively, but the answer is far from simple.

Large studies have not found a convincing overall association between early-life cat or dog ownership and the later risk of asthma or allergic sensitization.

Other reviews have also reported inconsistent findings.

It is especially important to remember that for a child who is already sensitized to a particular animal, continued exposure may actually worsen symptoms.

So adopting a cat or dog specifically to “prevent allergies” is not recommended.

💚 How can pets still contribute to disease prevention?

The best-supported mechanism is surprisingly ordinary.

There is no mysterious “healing substance” produced by dogs or cats.

Pets can change the way we live.

A dog gets us out of the house.

A walk gets us moving.

Being outside brings us into contact with other people.

A pet creates a daily routine.

They provide social contact and give us someone to care for.

All of these things may encourage behaviors that are themselves associated with better health.

Physical activity is the clearest example.

Regular movement is proven to reduce the risk of cardiovascular disease, stroke, type 2 diabetes, some cancers, dementia and premature death.

⚠️ But there is another side to the story

Any discussion of the health benefits of pets would be incomplete without acknowledging the risks.

Cats and dogs can carry infections, parasites and zoonotic pathogens.

Extra caution may be needed for:

• young children

• older adults

• pregnant people

• people with weakened immune systems

Regular veterinary care, vaccination, parasite prevention, hand hygiene and safe handling of animal waste can significantly reduce these risks.

People with allergies or asthma should also discuss pet ownership with their doctor when appropriate.

🐾 The MačkaPas takeaway

A cat or dog is not medicine and certainly not a reason to avoid seeing a doctor.

But pets are more than just a pleasant addition to the home.

Science points to several very real ways in which animals can support human health.

Dogs encourage people to move more and may therefore indirectly contribute to the prevention of chronic disease.

Cats and dogs provide social contact and emotional support.

Specially trained dogs support some people with diabetes, epilepsy and PTSD, although their capabilities have important limitations.

Animal-assisted interventions may improve certain symptoms and quality of life for people with dementia and some other conditions.

The most important thing is not to turn genuine scientific findings into magic.

A pet cannot promise you lower blood pressure, freedom from depression or a longer life.

But they can bring more movement, companionship, attachment, routine and the feeling that someone is waiting for you at home.

And that is already quite a lot. ❤️