One of the first demonstration of relationships between pets and health was an early study of 92 heart-attacks in which 28% of pet owners survived for at least a year as compared to only 6% of non-pet owners (Friedmann et al., 1980).
In a survey by Wood et al., 2011, the odds of feeling lonely were twice as high in non pet owners than in pet owners. Pet owners were also significantly more likely to report excellent or very good health compared to non-pet owners fewer pet owners reported a diagnosed mental health problem, that is, 17.8% compared to 21.6% (non-pet owners).Among 11,000 German and Australian adults pet owners were in better physical condition that non-pet owners, and they made 15% fewer doctor visits and a better mental well-being (Harold Herzog, 2011).
A study found that changes in pet ownership at different times in the life cycle affected feelings of attachment and it was concluded that pet attachment was particularly important among divorced, never married, widowed, childless and newly weds, because pets both give and receive affection (Albert and Bulcroft, 1988). In another research an interview study of 81 widowed women, ranging from 1 to 3 years, it explored variables related to adjustment following the loss of their spouse and comments such as “I feel they patronize me” and “I’m a dropout of society” were given by two women describing how they perceived the support of their friends whereas women referred to their pets in a positive, affectionate way and reported significantly less loneliness (Sable P., 1991). In another study, 45 women were exposed to a stressful stimulus alone, in the presence of a human friend, and in the presence of their dog.
Their autonomic nervous system responses to stress, such as heart rate, were measured. The stress response was marked when subjects were alone, and even more marked when a friend was present. But having a dog present significantly reduced the stress response (Horward Frumkin, 2001).
Allen et al., 2001, conducted a clinical trial in which hypertensive stockbrokers were randomly assigned to either pet or no-pets condition. Six months later, when put in a stressful situation subjects in the pet group showed lower increases in blood pressure than the non-pet group. A study of chinese women found that pet owners exercised more, slept better, felt more physically fit and missed fewer days from work than women without pets (Harold Herzog, 2011). In one study, patients about to undergo oral surgery were randomly assigned to one of five conditions: a half-hour looking at an aquarium, with or without hypnosis; a half-hour looking at a picture of a waterfall, with or without hypnosis; and a half-hour of sitting quietly.
The patients’ comfort and relaxation during surgery were graded independently by the oral surgeon, the investigator, and the patients themselves. The most relaxed patients were those who looked at the aquarium, irrespective of whether they had been hypnotized. The patients who looked at the waterfall picture were almost as relaxed, but only if they had been hypnotized first. Otherwise, they had low relaxation scores, as low as those of the control patients (Allen D.T, 1997).