Do pets lower risk of allergies
Pets alter infants' microbiota to lower risk of allergies, obesity
New research highlights the benefits of having pets around the house during childhood, after finding that early-life exposure to furry animals may reduce the risk of developing allergies and obesity.
Led by researchers from the University of Alberta in Canada, the study found that children exposed to dogs, cats, and other furry pets in early life before birth and up to 3 months after experienced significant increases in two beneficial gut bacteria: Ruminococcus and Oscillospira.
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Study co-author Anita Kozyrskyj, of the Department of Pediatrics at Alberta, and colleagues recently reported their
According to The Humane Society of the United States, around 79.7 million households in the U.S. own at least one animal, with dogs taking the top spot as most popular pet.
Our four-legged friends undoubtedly bring us joy and companionship, but studies have shown that their benefits do not end there, particularly for children.
One study reported by Medical News Today last year, for example, found that dog exposure in the first year of a childs life was associated with a 13 percent decreased asthma risk in later childhood.
It has been suggested that such associations are down to changes in gut microbiota the population of microorganisms in the intestines as a result of exposure to bacteria from pets.
To find out more about how pet exposure in early life might influence the gut microbiota of children, Kozyrskyj and colleagues analyzed data from the Canadian Healthy Infant Longitudinal Development Study (CHILD) cohort, including 746 infants who were born between 2009 and 2012.
As part of the study, the infants mothers were required to report any household pets owned during the second and third trimester of pregnancy, as well as 3 months after birth.
Around 46 percent of infants were exposed to household pets before and after birth, the team reports. Dogs accounted for around 70 percent of household pets.
Fecal samples were collected from each infant around the age of 3 months and analyzed to determine the abundance of specific gut bacteria.
The researchers found that infants who were exposed to furry animals before and after birth demonstrated a twofold increase in the abundance of Ruminococcus and Oscillospira in their guts, compared with infants not exposed to household pets.
These findings remained even after accounting for three factors that can influence an infants gut bacteria: delivery by cesarean section, antibiotics during birth, and limited breast-feeding.
Furthermore, the team found that pet exposure prior to birth appeared to reduce the transmission of vaginal group B strep (GBS) from mother to child during delivery. GBS is associated with sepsis, pneumonia, and meningitis in newborns, although GBS infection can be prevented through intravenous antibiotics during pregnancy.
While further studies are needed to gain a better understanding of how early-life pet exposure affects bacterial populations, Kozyrskyj and team believe that their findings support previous studies showing that household pets can benefit childrens health.
The researchers write:
[] exposure to pets increased the abundance of two bacteria, Ruminococcus and Oscillospira, which have been negatively associated with childhood atopy and obesity.
[] In addition, our finding of reduced streptococcal colonization with prenatal pet ownership may lower the risk for childhood metabolic and atopic disease. Further research is needed to link the pet-related microbiota changes with health outcomes of infants in the CHILD cohort, as well as in other populations.
The researchers say that it is too soon to make conclusions about the new treatments such research could bring, but Kozyrskyj believes that a dog in a pill could be feasible.
Its not far-fetched that the pharmaceutical industry will try to create a supplement of these microbiomes, much like was done with probiotics, she says.
Learn how childhood pets may surpass siblings when it comes to relationship satisfaction.
Having A Pet Can Lower Your Babys Risk For Allergies
The benefits of having a pet are endless even for the smallest members of the family.
Research shows that during a babys first year (and even during pregnancy!), being around pets may increase immunity, which can reduce the risk of allergies developing in children.
Isnt that cool? Researchers call this the hygiene hypothesis, which is the theory that the cleaner we live, the more prone we are to asthma and allergies.
We spoke with Dr. Leah Alexander, a pediatrician and consultant for Mom Loves Best, for more insight on the connection between having a pet and your babys risk for allergies.
Reasons why pets may lower your babys risk for allergies
Environmental allergies are actually pretty common in children, unfortunately (40 percent of children reportedly suffer from allergies in the U.S.).
Recent research has shown that exposure to animals early in life, including household pets, can have a protective effect against the future development of allergies, Dr. Alexander told The Dodo.
According to Dr. Alexander, there are a few theories for why this happens:
- Being around pets during infancy primes the intestines with healthy bacterial flora which reduces the sensitization to allergens. This has mostly been seen in infants who arent exposed to vaginal flora because of a cesarean section birth.
- It can also promote the development of immune tolerance in a dose-dependent way; the number of pets and amount of contact increase the level of protection.
- Some studies show not only a reduction in future allergies but also asthma and atopic dermatitis. However, the time frame is critical contact should begin prior to their first birthday. After a year, the risk of allergies and asthma increases.
Pets can reduce the risk of eczema, too
Having a pet can actually lower your babys risk for all sorts of allergies, like eczema, for example. New research suggests that a dogs diverse bacteria could help a childs immune development, and can offer children significant protection against the inflammatory condition, which causes the skin to become itchy, dry and cracked.
Other factors that reduces the risk of allergies in kids
While research confirms that children who are around pets (particularly dogs and cats) in the first year of life may suffer less from allergies, wheezing and asthma, other factors can contribute to a lower risk of allergies, too:
- Interaction with siblings
- Exposure to day care
- Genetics (Children have a one in three chance of developing allergies if just one of their parents has them, and a 70 percent chance if both parents have allergies.)
While researchers arent saying that new parents should rush out and adopt a dog or cat, adults with existing pet allergies should take that into consideration, as well as the big responsibility that comes with caring for a pet.
But hey, if youve always wanted a pet maybe nows the time!
Are Pets the New Probiotic?
Scientists are paying increasing attention to the indoor microbiome, the billions of bacteria, viruses and fungi that we share our homes and offices with. But not all those micro-organisms are bad for us, experts note. And exposure to a rich array of indoor germs may actually be salutary, helping stave off a variety of illnesses.
So there is growing concern that, in our anxiety to banish bacteria from our indoor world, we have become too clean for our own good. We run the risk of scrubbing, disinfecting, vacuuming and filtering out the fortifying mix of microscopic creatures that our immune system needs to develop properly.
Enter the dog.
Dogs roll in the mud. They sniff feces and other questionable substances. Then they track countless germs into our homes on their paws, snouts and fur.
And if the latest research on pets and human health is correct, that cloud of dog-borne microbes may be working to keep us healthy. Epidemiological studies show that children who grow up in households with dogs have a lower risk for developing autoimmune illnesses like asthma and allergies and it may be a result of the diversity of microbes that these animals bring inside our homes.
According to the so-called hygiene hypothesis, spending over 90 percent of our time in the bacteria-poor environment indoors, as we do (especially early in life, when our immune systems are being formed), can cause our bodies to overreact to harmless substances later on, making us sick.
Allergies and asthma are both examples of the way that the immune system is misfiring, said Jordan Peccia, a professor of environmental engineering at Yale University. An allergy is our immune system attacking something that it shouldnt attack, because it hasnt been calibrated properly.
Dr. Peccia said exposure to animal micro-organisms during the first three months of life helps to stimulate a childs immune system so that it doesnt become overly sensitive later in life. A study published last year in The New England Journal of Medicine found that Amish children in Indiana who grew up close to barnyard animals had far lower rates of asthma than Hutterite children, who were raised apart from animals on large mechanized farms in North Dakota.
A co-author of the study, Jack Gilbert, the director of the Microbiome Center at the University of Chicago, said that the Amish suffer from fewer immune-related illnesses than the rest of us because they grow up with their livestock and the bacteria they host, as our human predecessors did for thousands of years.
When we are deprived of contact with these ancestral bacterial allies, our immune systems sometimes lose the ability to distinguish between friend and foe. The solution: If we cant bring our kids to the farm, maybe we can bring the farm to kids, said Dr. Gilbert, who believes that cohabitation with pets is the next best thing to living next door to a barnyard for training a growing immune system.
Our home environments already contain an abundance of microbes. An analysis of house dust collected by volunteers in a citizen science study called The Wild Life of Our Homes found more than 125,000 kinds of bacteria and 70,000-plus species of fungi in the participants dwellings.
Each of us sheds 38 million bacteria into our environment every hour. We breathe them out; they flake off our skin. Many of those bacteria die right away in the warm, dry air of our homes. But countless microbes survive in house dust or cling to the surfaces of things like computer screens and pillowcases.
Pets, and dogs especially, add a lot to the diversity of the indoor microbiome. Research has shown that dog ownership raised the levels of 56 different classes of bacterial species in the indoor environment, while naturally more fastidious cats boosted only 24 categories. We dont yet know if contact with feline microbes also helps prevent immune disorders; there have not yet been large enough studies to provide reliable data, Dr. Gilbert said. But we do know that indoor cats have less impact on the indoor microbiome than outdoor cats, he added.
For sure, some animal-borne microbes are not good for us, said Dr. Scarlett Magda, the president of the New York-based Veterinarians International, a nonprofit group that promotes human and animal health through veterinary care.
Dogs may, for example, lick the urine of rodents infected with leptospirosis, then lick us and transmit the bacteria through breaks in the skin, though only a handful of cases of leptospirosis are reported in New York City each year, and its not known if any were caused by pets.
Cats are well-known carriers of toxoplasmosis. And pet turtles and frogs (and occasionally dogs and cats) can carry salmonella bacteria on their skin and in their feces. But not to worry, said Dr. Magda: Just wash your hands.
The potential upsides of pet ownership appear to outweigh the risks and continue to be elucidated.
Some intriguing early research suggests links between the microbes that our animal companions bring into our homes and that we breathe in and swallow and the microbes that thrive in our digestive tract. Exposure to animal bacteria may trigger bacteria in our gut to change how they metabolize the neurotransmitters that have an impact on mood and other mental functions, Dr. Gilbert said, although he cautioned that research into how pet microbes affect the human gut microbiome remains at an early stage.
Netzin Steklis, a biologist at the University of Arizona who is working on a study of the elderly to learn more about how living with dogs changes their skin and gut microbiomes, says that pet owners have long known that animal companionship can lift our mood. But it is not just an oxytocin story anymore, she said, referring to the brain chemical often called the hormone of love. She suspects that the physiological effect of their bacteria in our guts may contribute to the well-known antidepressive benefit of pet ownership.
Dogs have been with humans for 40,000 years, she said. But we are only now looking to find out how living with them impacts our health. Well know more soon.
