Research looks at how living and working with dogs impacts ageing and stress levels
Owning or working with man’s best friend could slow down biological ageing in women, according to a new study. The research, which focused on female former soldiers, is among the first to examine the impact of working with service dogs.
Scientists measured biological indicators of stress and discovered that the way stress is felt emotionally doesn’t always reflect how it affects the body at a cellular level. They suggest that non-pharmacological interventions – such as service dog training – may help reduce the physical toll of stress and slow cellular ageing.
A research team, led by scientists from Florida Atlantic University (FAU), conducted a study in female veterans with post-traumatic stress disorder (PTSD) who served in the US military. Instead of receiving service dogs, the women volunteered to train them for other veterans.
The study, published in the journal Behavioural Sciences, examined whether this purposeful, mission-driven activity could reduce both biological and psychological stress, and whether previous combat exposure influenced those effects.
Female veterans aged between 32 and 72 were randomly assigned to either a service dog training programme or a comparison group that watched dog training videos. Both groups participated in one-hour sessions each week for eight weeks.
The research team measured biological stress by examining telomere length – a marker of cellular ageing – using saliva samples, and heart rate variability (HRV), an indicator of nervous system balance. Psychological stress was monitored using questionnaires measuring PTSD symptoms, perceived stress, and anxiety at multiple points during the study.
The findings revealed “promising” biological benefits associated with service dog training – particularly for veterans with combat experience – while improvements in psychological symptoms were seen across all participants, regardless of the intervention. One of the most “striking” findings involved telomere length.
Veterans who took part in the dog-training programme showed an increase in telomere length, suggesting a slowing of cellular ageing. However, those in the control group exhibited a decrease in telomere length, indicating accelerated ageing. Combat experience significantly influenced the results.
Veterans exposed to combat who trained service dogs saw the most significant increase in telomere length, while those with combat exposure in the control group experienced the most noticeable declines. Both groups, those who trained dogs and those in the control group, reported “significant” reductions in PTSD symptoms, anxiety and perceived stress over the eight-week period.
The mental health improvements were similar across groups, suggesting that simply participating in the study and receiving structured attention may have offered therapeutic value. Study first author Professor Cheryl Krause-Parello, associate vice president for FAU research, said: “Female veterans face unique reintegration challenges that are often overlooked, and traditional PTSD treatments don’t always meet their needs.
“Non-traditional approaches like connecting with animals can offer meaningful support. These relationships provide emotional safety and stability, which can be especially powerful for women.
“But not all veterans can care for a service animal, so animal-related volunteerism may offer similar healing benefits without the burden of ownership.”
She says the study also suggests that skills learned during service dog training – such as positive reinforcement and reading animal behaviour – may have strengthened participants’ bonds with their own pets at home, offering additional emotional support. Prof Krause-Parello stated: “Unlike general volunteering, service dog training uniquely blends emotional healing with building a close relationship between veterans and their animals, providing therapeutic benefits that go beyond typical community engagement.”
She continued: “This research underscores the power of service dog training as a meaningful, non-pharmacological intervention to support the health and healing of female veterans with PTSD. It opens the door to more personalised approaches that nurture both the mind and body.”