World Dog Day: Health Benefits of Living with Dogs

On World Dog Day, marked on 26 August, science offers fresh reasons to view the relationship between people and dogs as more than companionship and affection. Studies suggest that living with a pet may be linked to a range of health benefits, from protection against infections during the earliest years of life to positive effects on emotional wellbeing.

The study “The role of dog keeping in the home microbiota and its impact on children’s health”, published in the journal Pediatric Allergy and Immunology, presented findings on the connection between pets and strengthening babies’ bodies. According to the research, exposure to bacteria commonly found in homes with dogs can reduce the need for antibiotics in early childhood by up to 25%.

Dr Carolina Affonseca, coordinator of the postgraduate course in Paediatrics at Afya Educação Médica Belo Horizonte, says the benefit does not appear to result simply from a greater quantity or diversity of microorganisms in the home, but rather from particular groups associated with the presence of a dog.

“One explanation involves stimulating the immune system while it is still developing. Early contact with different environmental microorganisms may help train components of innate immunity and encourage more balanced responses to common infections. Another possible route concerns the gut microbiome. Studies have found differences in the composition of this microbiota among babies living with dogs, including a greater diversity of bacterial groups during the first 18 months of life and a higher presence of bacteria,” she explains.

Specific microorganisms may account for part of the association

The research followed babies from their ninth to 52nd week of life, examining episodes of fever and ear infections, the number of weeks considered healthy, and antibiotic use, as well as samples of household dust. Dr Carolina Affonseca explains that, when researchers assessed dust from the homes, they identified certain groups of bacteria and fungi associated with dogs, including bacteria from the Pasteurella genus. These specific microorganisms could statistically explain around 10% to 25% of the observed association between having a dog at home and lower rates of fever, ear infections and antibiotic use.

“An interesting point is that the potential benefit does not seem to depend merely on a home having a larger quantity or diversity of microorganisms. The total microbial richness of the dust, the overall concentration of bacteria and the proportion of bacteria of human origin did not explain the association. The effect appears to be linked above all to particular microorganisms connected with the presence of the dog,” the doctor adds.

Benefits of living with dogs

In adulthood, the benefits of living with a dog also continue to build, with significant effects on the mind and emotional wellbeing. The “Survey: Pet Owners and the Human-Animal Bond September 2016”, conducted by the Human Animal Bond Research Institute (HABRI) in partnership with the Cohen Research Group, found that 74% of owners reported substantial improvements in their mental health because of their bond with pets. The findings indicate that an animal’s presence can ease depression, anxiety, stress and loneliness, while boosting self-esteem and encouraging social interaction.

Sabrina Magalhães Teixeira, psychology coordinator at Afya Sete Lagoas, says three mechanisms help explain the benefits of living with dogs for people:

• Physiological: physical and visual contact with dogs activates the oxytocin-mediated neuroendocrine system. Oxytocin is an important hormone in the formation of bonds. Stroking a dog may increase oxytocin while lowering cortisol levels and heart rate, helping to manage stress and increase wellbeing and feelings of security;
• Psychological: this is linked to attachment theory and to seeing the dog as a “secure base”. The animal’s presence may lessen feelings of threat and fear, supporting wellbeing, security and the ability to cope with everyday challenges;
• Social: a dog may be regarded as a source of support and companionship, helping to reduce loneliness, reinforce self-esteem and foster a sense of purpose through caring for and bonding with the animal.

“It is important to stress that this bond is not automatic. Having an animal alone does not guarantee these benefits; the relationship between owner and animal must also be built and nurtured. Through these mechanisms, living together may be associated with reduced stress, anxiety and worries, as well as stronger self-esteem, security, emotional regulation and a sense of purpose and responsibility,” Sabrina Magalhães Teixeira explains.

By Matheus Garcia