A cat purring on your lap. A dog's tail going at the door before you have your key out of the lock. If anything has ever taken the edge off a bad day without saying a word, it was probably one of those. Try getting that from a colleague.
The idea that pets are good for you is so familiar that it sounds like a fact. It is partly a fact. Some of what gets claimed for animals holds up well, some holds up only in the moment, and one of the biggest findings is usually left off the list altogether.
One simple and often overlooked help might be sitting right at your feet, or perched on your shoulder. Here are the five benefits most often promised for it, each put to the test, and then the one that was missing.
1. Calmer, in ten minutes
The usual claim is that animals lower your stress hormone and raise your bonding hormone. For petting, that is roughly what has been measured.
When 249 university students were split into four groups, one group spent ten minutes petting cats and dogs. Another watched other people pet them, another looked at photos of the same animals, and the last just waited. Afterwards, the students who had their hands on the animals had lower cortisol, the stress hormone, than all three of the others. Looking was not enough. Touch did it. Scrolling past cat photos, it turns out, is not the same thing.
The animal gets something out of it too. After a spell of friendly contact between dog lovers and dogs, a whole set of feel-good chemicals rose in both species. Among them were the body's own painkillers, the bonding hormone oxytocin, and dopamine, the chemical of reward. Cortisol fell in the people.
Dogs have even learned to start the process themselves. When dogs gazed into their owners' eyes, the owners' oxytocin rose, and they stroked and talked to the dogs more. Then the dogs' oxytocin rose in turn, a loop that feeds itself. Wolves did not. Somewhere in the long history of dogs living with us, the look became part of the bond.
They can read you back. Breath and sweat were collected from 36 people before and after a stressful arithmetic task, and four trained dogs were asked to pick out the stressed sample. They got it right 93.75% of the time. Your dog may know you have had a bad day before you have taken your coat off.
Under pressure, animals help too. The Invisible War Inside Your Body (And How to Win It) has the strange dog that calmed people more than a friend did. How Stress Spreads Through Families and Why Your Nervous System Fights Some Stress Techniques, both linked below, have the pet in the room during a stressful test, and the owner's own dog against a friend.
The verdict is yes, for the moment you are with them.
2. A better mood
Pets are masters of unconditional love, and it is easy to assume that owning one keeps depression away. Here the evidence gets less friendly.
Some findings show pet owners doing better. Others show them no healthier or happier than anyone else, and a few show them doing worse. Anyone who has been woken before dawn by a cat demanding breakfast will understand. Looking across the lot, one reviewer of the field concluded that a general "pet effect" on health and happiness is not yet a fact, but an unproven idea. His book is about why we think so crookedly about animals in the first place.
There are good reasons the results disagree. People who choose a pet differ from people who do not, in money, health, home and time. A dog can lift a lonely life, and a sick dog, a dog that bites or a dog you cannot afford can weigh one down. Grief comes with the deal too. Losing a pet can hurt as much as losing a person, sometimes more, and there is no set time for it to pass. It is the price of the love, paid at the end.
The clearest sign comes from children. Among 643 children aged 4 to 10 brought in for routine check-ups, 12% of those with a dog at home screened positive for anxiety, against 21% of those without. Their weight, screen time and activity did not differ. It was one look at one moment, so it shows a link, not a cause, but it is the kind of link worth noticing.
So the lift in the moment is real. A cure for low mood has not been shown. The verdict is sometimes, depending on the person.
3. More movement
This is the claim with the strongest backing, and it is mostly about dogs.
Among 191 dog owners and 455 people without dogs in Cheshire, the owners were 14 times more likely to walk for pleasure. They were four times more likely to reach 150 active minutes a week. Their other exercise did not drop to make room for the walks. The dog added walking to their week.
That walking may be what matters most later in life. Among 11,194 older adults in Japan followed for about four years, dog owners had 40% lower odds of developing dementia severe enough to need care, even after they were matched with people of similar health, habits and social lives. Cat owners showed no difference. The lowest odds of all were in dog owners who also exercised regularly. The cat, it seems, does not take you anywhere.
A dog that needs walking is a personal trainer who never cancels and does not take no for an answer. Win the Morning, Win the Day: Simple Rituals That Separate High Achievers from the Rest has what decides whether owners actually go: the bond with the dog. The verdict is yes.
4. More people
Pets are often great icebreakers. Here, the measurement agrees.
When 2,692 people in Perth, San Diego, Portland and Nashville were asked how they had got to know their neighbours, pet owners were about one and a half times as likely as non-owners to have got to know people nearby. Some had made real friends through their animals, and some had found people to lean on.
It is hard to walk past someone whose dog has just sat on your foot. The verdict is yes, especially with a dog that gets you out of the door.
5. A sense of purpose
Caring for an animal gives the day a shape. Pets depend on you to be fed, walked, cleaned up after and noticed, and that routine can steady a life that has lost its own.
People have used that for a long time. In the late 1700s, the York Retreat in England, a Quaker asylum, brought animals into the care of its patients. In 1859, Florence Nightingale wrote that "a small pet animal is often an excellent companion for the sick".
Sigmund Freud kept his chow, Jofi, in the room during his sessions. He found that patients relaxed with the dog there, because nothing they said shocked or upset the dog. In 1961, Boris Levinson left his dog alone with a child who would not speak, and came back to find the child talking to the dog. The dog, unlike the analyst, never took notes.
Purpose is hard to measure, and it has been measured least. The stories are old and consistent. The verdict is likely, but untested.
The one the list missed: your heart
Here is the finding the usual pet lists leave out, and it is the biggest.
When 10 long-term follow-ups covering 3,837,005 people were pooled, dog owners were 24% less likely to die over about ten years than people without dogs. After a heart attack or other heart event, the drop was 65%. Deaths from heart disease were 31% lower.
In Sweden, 3,432,153 adults were followed for up to 12 years. Dog owners who lived alone were 33% less likely to die than people living alone without a dog, and owners in bigger households 11% less.
Cats have a case too. Among 4,435 Americans followed for about 20 years, people who had owned a cat in the past were 37% less likely to die of a heart attack. That held after allowing for age, sex, blood pressure, smoking, diabetes, cholesterol and weight.
Before anyone runs to the shelter, two catches. The pooled figures were not adjusted for other differences between owners and non-owners, and healthier, more active people may simply be the ones who get dogs. And in a smaller group from the Swedish twin register, with more detail on health and habits, the drop did not show. So a dog goes with a longer life. Whether the dog causes it is not settled.
What has been tested directly is smaller, and it points the same way. Among 76 people in hospital with advanced heart failure, some got a 12-minute visit from a volunteer with a therapy dog. Compared with ordinary care, it lowered the pressures inside the heart and lungs. It cut adrenaline and its partner noradrenaline more than a visit from the volunteer alone, and it eased anxiety more than either. Twelve minutes, a dog, and a measurably calmer heart.
The cost of a pet
Animals are not a free remedy, and the honest list includes what they take.
In the United States, about 86,629 people a year end up in emergency departments after a fall involving a cat or a dog, 88% of them with dogs. Women were hurt about twice as often as men. It takes one lead around the ankles. A pet is love on four legs, and now and then under your two. Bites are the other risk. About 4.5 million Americans are bitten by a dog each year, most of them children, and nearly half of American children have been bitten by the age of 12.
Pets bring germs into the kitchen, too. Good Hygiene: The Everyday Habits That Matter Most has why you should wash your hands after feeding, stroking or cleaning up after them.
If allergies are what holds you back, the evidence runs the other way from what you might expect. Among 474 children in Detroit followed from birth, 33.6% of those with no dog or cat in their first year were allergic to common triggers by the age of 6 or 7. With one pet it was 34.3%. With two or more, it was 15.4%. Unconventional Remedies for Chronic Allergies has why growing up around animals seems to teach the immune system to stay calm.
Then there is the money, the time, the holidays you plan around them, and the vet bills. A pet is a commitment that lasts its whole life, not a prescription you can stop when the stress passes.
No pet? Borrow one
You do not need to own an animal to get the moment of calm. The students' ten minutes came from visiting animals, not living with them. Volunteering at a local animal shelter gives you the walks, the stroking and the routine, and the shelter gets a pair of hands.
You do not even need fur. As a large aquarium tank was restocked with fish, visitors looked for longer, their heart rates dropped further and their mood rose more with every stage. More fish, more calm.
Or skip the touching altogether. When 1,292 people answered 26,856 short check-ins on their phones, moments when they could see or hear birds went with better mental wellbeing, and the lift lasted well beyond the moment. It held in people with depression too. A bird feeder outside the window brings them to you. A stuck to the glass puts them close enough to watch from your chair.
Be here now
Animals have a unique way of reminding us to be present. A dog does not worry about tomorrow's meeting, and a cat has never once checked its phone. Ten minutes with either brings your attention back to the warm, breathing thing in front of you.
Take the ten minutes today. Put your hand on an animal, yours, a neighbour's or a shelter's, and leave your phone in the other room.
Calmer with a pet in the room? How Stress Spreads Through Families — the couples who did arithmetic with a hand in ice water, and why the pet beat the spouse.
Why a dog, and not a friend? Why Your Nervous System Fights Some Stress Techniques — the women who reacted least with their own dog in the room, and other ways to work with your body instead of against it.
Know someone who would be calmer with a dog? Send them this, and the catch that comes with it.
Disclaimer: This article is general information. For advice about your own health, stress or mood, talk to a qualified health professional.
Affiliate Disclosure: This article contains affiliate links. As an Amazon Associate, All For Life earns from qualifying purchases, at no extra cost to you. We only link to products we would recommend without the commission.
Sources
Pendry P, Vandagriff JL (2019). Animal Visitation Program (AVP) Reduces Cortisol Levels of University Students: A Randomized Controlled Trial. AERA Open 5(2). doi.org/10.1177/2332858419852592
Odendaal JSJ, Meintjes RA (2003). Neurophysiological Correlates of Affiliative Behaviour between Humans and Dogs. The Veterinary Journal 165(3):296–301. doi.org/10.1016/s1090-0233(02)00237-x
Nagasawa M, Mitsui S, En S, et al. (2015). Oxytocin-gaze positive loop and the coevolution of human-dog bonds. Science 348(6232):333–336. doi.org/10.1126/science.1261022
Wilson C, Campbell K, Petzel Z, Reeve C (2022). Dogs can discriminate between human baseline and psychological stress condition odours. PLOS ONE 17(9):e0274143. doi.org/10.1371/journal.pone.0274143
Polheber JP, Matchock RL (2014). The presence of a dog attenuates cortisol and heart rate in the Trier Social Stress Test compared to human friends. Journal of Behavioral Medicine 37(5):860–867. doi.org/10.1007/s10865-013-9546-1
Allen K, Blascovich J, Mendes WB (2002). Cardiovascular reactivity and the presence of pets, friends, and spouses: the truth about cats and dogs. Psychosomatic Medicine 64(5):727–739. doi.org/10.1097/01.psy.0000024236.11538.41
Allen KM, Blascovich J, Tomaka J, Kelsey RM (1991). Presence of human friends and pet dogs as moderators of autonomic responses to stress in women. Journal of Personality and Social Psychology 61(4):582–589. doi.org/10.1037/0022-3514.61.4.582
Herzog H (2011). The Impact of Pets on Human Health and Psychological Well-Being. Current Directions in Psychological Science 20(4):236–239. doi.org/10.1177/0963721411415220
Wikipedia. Animal loss. en.wikipedia.org
Gadomski AM, Scribani MB, Krupa N, et al. (2015). Pet Dogs and Children's Health: Opportunities for Chronic Disease Prevention? Preventing Chronic Disease 12:E205. doi.org/10.5888/pcd12.150204
Westgarth C, Christley RM, Jewell C, et al. (2019). Dog owners are more likely to meet physical activity guidelines than people without a dog: An investigation of the association between dog ownership and physical activity levels in a UK community. Scientific Reports 9:5704. doi.org/10.1038/s41598-019-41254-6
Taniguchi Y, Seino S, Ikeuchi T, et al. (2023). Protective effects of dog ownership against the onset of disabling dementia in older community-dwelling Japanese: A longitudinal study. Preventive Medicine Reports 36:102465. doi.org/10.1016/j.pmedr.2023.102465
Westgarth C, Christley RM, Christian HE (2014). How might we increase physical activity through dog walking?: A comprehensive review of dog walking correlates. International Journal of Behavioral Nutrition and Physical Activity 11:83. doi.org/10.1186/1479-5868-11-83
Wood L, Martin K, Christian H, et al. (2015). The Pet Factor - Companion Animals as a Conduit for Getting to Know People, Friendship Formation and Social Support. PLOS ONE 10(4):e0122085. doi.org/10.1371/journal.pone.0122085
Wikipedia. Animal-assisted therapy. en.wikipedia.org
Wikipedia. York Retreat. en.wikipedia.org
Nightingale F (1859). Notes on Nursing: What It Is, and What It Is Not. gutenberg.org
Kramer CK, Mehmood S, Suen RS (2019). Dog Ownership and Survival. Circulation: Cardiovascular Quality and Outcomes 12(10):e005554. doi.org/10.1161/CIRCOUTCOMES.119.005554
Mubanga M, Byberg L, Nowak C, et al. (2017). Dog ownership and the risk of cardiovascular disease and death – a nationwide cohort study. Scientific Reports 7:15821. doi.org/10.1038/s41598-017-16118-6
Qureshi AI, Memon MZ, Vazquez G, Suri MF (2009). Cat ownership and the Risk of Fatal Cardiovascular Diseases. Results from the Second National Health and Nutrition Examination Study Mortality Follow-up Study. Journal of Vascular and Interventional Neurology 2(1):132–135. pubmed.ncbi.nlm.nih.gov
Cole KM, Gawlinski A, Steers N, Kotlerman J (2007). Animal-assisted therapy in patients hospitalized with heart failure. American Journal of Critical Care 16(6):575–585. pubmed.ncbi.nlm.nih.gov
Centers for Disease Control and Prevention (2009). Nonfatal Fall-Related Injuries Associated with Dogs and Cats — United States, 2001–2006. Morbidity and Mortality Weekly Report 58(11):277–281. cdc.gov
Wikipedia. Dog bite. en.wikipedia.org
Ownby DR, Johnson CC, Peterson EL (2002). Exposure to Dogs and Cats in the First Year of Life and Risk of Allergic Sensitization at 6 to 7 Years of Age. JAMA 288(8):963–972. doi.org/10.1001/jama.288.8.963
Stein MM, Hrusch CL, Gozdz J, et al. (2016). Innate immunity and asthma risk in Amish and Hutterite farm children. New England Journal of Medicine 375(5):411–421. doi.org/10.1056/NEJMoa1508749
Cracknell D, White MP, Pahl S, et al. (2016). Marine Biota and Psychological Well-Being: A Preliminary Examination of Dose-Response Effects in an Aquarium Setting. Environment and Behavior 48(10):1242–1269. doi.org/10.1177/0013916515597512
Hammoud R, Tognin S, Burgess L, et al. (2022). Smartphone-based ecological momentary assessment reveals mental health benefits of birdlife. Scientific Reports 12:17589. doi.org/10.1038/s41598-022-20207-6