Pet lovers unite!
Do you have an extra lint-roller to get the animal hair off your black pants? Got a ball or two wedged under the couch? Is your cat perched atop your warm computer? Congratulations! You are on your way to a healthy microbiome.
It’s been established that pets have the capacity to make us healthier. They can inspire us to exercise which increases our physical health. They can provide camaraderie which lessens loneliness and depression and improves our mental health. And more recent research suggests that they can increase microbial diversity to advance our overall health.
The Benefits of Exercising with our Pets
Most dog owners get more exercise per week than people who are not dog walkers. A study of the UK showed that dog owners walked 7 times per week, and averaged 220 minutes of walking per week.1 In fact in this study, 88% of dog walkers met physical activity guidelines each week, whereas only 29% of people who don’t have dogs met the same guidelines. In fact, dog owners run or jog more often – even without their dog!1
Running or walking with our dogs has widespread health effects, including microbiome health. The World Health Organization recommends that women get 150 minutes of aerobic movement per week and this level of exercise has been shown to modify the microbiome.2 Specifically, women who exercised, according to WHO guidelines, had a higher abundance of health-promoting bacterial species, including Faecalibacterium prausnitzii, Roseburia hominis and Akkermansia muciniphila.2 These microbes also correlate with a decreased body fat percentage and increased muscle mass. If walking or running a dog provides an excuse for people to exercise, it’s expected that similar changes in the microbiome occur due to movement, whether you have a pet or not.
The Benefits of Cuddling with our Pets
But our relationships with our pets go beyond exercise. They’re companions that we can pet and cuddle. Everyone from school age children, to veterans, and elderly people claim that cuddling a pet can help them cope with stress.3,4,5 In these studies, even ninety minutes per week reduced depression, although the results weren’t significant.6 Ninety minutes per week – not per day. What are these pets doing that is so transformative? Some research suggests that both the pet and its owner experience a surge in oxytocin when they snuggle.7
Why does cuddling our pet release oxytocin? We commonly think of oxytocin as the “bonding” hormone. Oxytocin is released when mothers breastfeed their infants and is thought to bond mother and child.8 Additional research has shown that oxytocin can be released during nurturing and love to reveal general sense of well-being extending to physical, mental, social, and spiritual health.<sup>8</sup> Oxytocin decreases the HPA axis to relieve stress. And isn’t that the relationship we have with our pets? We bond, nurture, and love them. They reduce our stress (except when they’ve eaten our shoes or destroyed our couch).
Do we Share a Microbiome with our Pets?
Are we picking up our pet’s microbes when we pet them, kiss them, and live with them? Research from the 1980’s showed that dogs and their humans shared many of the same microbes.9 However, at that time, the technology was unable to examine a large percentage of microbes. A 2020 study from the University of Wisconsin used 16S RNA to measure microbes in stool of 178 pet owners (mostly dogs and cats) vs 154 people who didn’t have pets. They (re)discovered that pet owners had differences in their microbiome. While there were not enough differences between the two groups to see differences in alpha or beta diversity, L. gasseri and B. cellulosilyticus were more prevalent in those with no pets while C. oroticum and A. muciniphila were more prevalent in those with pets in the home. The relevance of these specific microbes is unknown, and confounders are abundant. But the discovery makes logical sense.
Animals groom themselves, licking every part of their body. And then we pet them. Microbial transfer is bound to occur.
An exciting Canadian study examined how prenatal and postnatal exposure to household pets affected the microbiome of the infant.10 In this study, households were grouped into 3 categories: those without pets; those that had prenatal pets; and those with prenatal and postnatal pets. Of the 746 infants, half were exposed to at least one furry pet in their prenatal/postnatal life (8% prenatal only; 46% prenatal and postnatal). Prenatal and postnatal pet exposure increased Oscillospira and/or Ruminococcus, microbes are associated with a healthy microbiome. But these researchers didn’t stop there. They noted that antibiotics is often associated with birth, and these antibiotics can lead to an overgrowth of Streptococcaceae. Excitingly, pet exposure reduced the Strep overgrowth! This is leading others to consider pets as a new microbiome-based therapy.11
What are the Benefits to owning (and cuddling) a Pet?
Through microbiome research, we are now starting to understand why large epidemiological studies have demonstrated that dog ownership is associated with lower childhood allergies and asthma.12 In this study, cat ownership didn’t reduce risk of asthma, nor did it increase it (odds ratio 1.0). However dog ownership in the first two years of life reduced risk of asthma in children aged 6-10 years old (odds ratio 0.77).
All of you goldfish, bird, and snake owners may be feeling left out right now. There is not a lot of research out there for these types of pets. A meta-analysis of bird only or rodent only (hamster, gerbil, mouse, etc) showed no effect of pet ownership on health outcomes.12 There have been a few studies looking at putting goldfish into a room with seniors, but the results have been inconclusive.
Before you rush right out and buy a dog, remember that many people aren’t prepared for the responsibility and cost associated with dog ownership. If you aren’t prepared for ownership, you may want to start with something like something like dog (or cat) sitting for a friend. If you’re ready for the next step, try “rent-a-pet” which is a service in some cities. You can rent a pet for a few hours, day, week, or month. Of course, at that point, you may not want to give it up. And you may need to invest in a lint roller.
- Westgarth C, Christley RM, Jewell C, German AJ, Boddy LM, Christian HE. 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. Sci Rep. 2019;9(1):5704. doi:10.1038/s41598-019-41254-6
- Bressa C, Bailén-Andrino M, Pérez-Santiago J, et al. Differences in gut microbiota profile between women with active lifestyle and sedentary women. PLOS ONE. 2017;12(2):e0171352. doi:10.1371/journal.pone.0171352
- Sharrer VW, Ryan-Wenger NM. A longitudinal study of age and gender differences of stressors and coping strategies in school-aged children. J Pediatr Health Care Off Publ Natl Assoc Pediatr Nurse Assoc Pract. 1995;9(3):123-130. doi:10.1016/s0891-5245(05)80020-3
- Mims D, Waddell R. Animal Assisted Therapy and Trauma Survivors. J Evid-Inf Soc Work. 2016;13(5):452-457. doi:10.1080/23761407.2016.1166841
- Cherniack EP, Cherniack AR. The benefit of pets and animal-assisted therapy to the health of older individuals. Curr Gerontol Geriatr Res. 2014;2014:623203. doi:10.1155/2014/623203
- Pet therapy in elderly patients with mental illness - MORETTI - 2011 - Psychogeriatrics - Wiley Online Library. Accessed February 27, 2022. https://onlinelibrary-wiley-com.liboff.ohsu.edu/doi/full/10.1111/j.1479-8301.2010.00329.x
- Petersson M, Uvnäs-Moberg K, Nilsson A, Gustafson LL, Hydbring-Sandberg E, Handlin L. Oxytocin and Cortisol Levels in Dog Owners and Their Dogs Are Associated with Behavioral Patterns: An Exploratory Study. Front Psychol. 2017;8. Accessed March 1, 2022. https://www.frontiersin.org/article/10.3389/fpsyg.2017.01796
- Erdman SE. Oxytocin and the microbiome. Curr Opin Endocr Metab Res. 2021;19:8-14. doi:10.1016/j.coemr.2021.04.006
- Caugant DA, Levin BR, Selander RK. Distribution of multilocus genotypes of Escherichia coli within and between host families. J Hyg (Lond). 1984;92(3):377-384.
- Tun HM, Konya T, Takaro TK, et al. Exposure to household furry pets influences the gut microbiota of infant at 3–4 months following various birth scenarios. Microbiome. 2017;5:40. doi:10.1186/s40168-017-0254-x
- Salas Garcia MC, Schorr AR, Arnold W, Fei N, Gilbert JA. Pets as a Novel Microbiome-Based Therapy. In: Pastorinho MR, Sousa ACA, eds. Pets as Sentinels, Forecasters and Promoters of Human Health. Springer International Publishing; 2020:245-267. doi:10.1007/978-3-030-30734-9_11
- Lødrup Carlsen KC, Roll S, Carlsen KH, et al. Does Pet Ownership in Infancy Lead to Asthma or Allergy at School Age? Pooled Analysis of Individual Participant Data from 11 European Birth Cohorts. PLoS ONE. 2012;7(8):e43214. doi:10.1371/journal.pone.0043214