They protect against heart disease and soothe depression. These are not drugs, but our best friends

Children born into families with a dog are less likely to develop eczema. This is according to a recent study by scientists from the American College of Allergy, Asthma and Immunology. The protective effect resulting from contact with a pet lasts up to 10 years of age – later it decreases. The dependence is especially pronounced in the case of children under the age of two. Eczema is a term used to refer to a variety of inflammatory skin diseases such as atopic or seborrheic dermatitis. Some of them are allergic. The disease manifests itself as skin lesions in the form of red lumps which form vesicles. If they become infected, purulent discharge may appear. It is quite easy to achieve such an effect, because another symptom of eczema is itching, which is conducive to scratching the affected skin – especially in children.

The same group of scientists also conducted two studies involving children with asthma. The first one concerned the impact of dog allergens on the health of babies. Second, other biological agents that come from dogs, such as bacteria. Contact with pets has been found to reduce the risk of developing asthma in children who are not allergic to canine-derived allergenic proteins. For toddlers with allergies – mostly in urban areas – the results were inconclusive. On the one hand, the study showed that exposure to allergens causes an allergic reaction, and on the other hand, contact with the dog brought about beneficial anti-asthmatic health effects. How exactly this mechanism looks like is unknown. According to the researchers, it may be microbial in origin, but there are other explanations as well. Recently, scientists from the University of Zurich have shown that sialic acid synthesized in the cells of some farm animals reduces inflammation in the respiratory tract.

Interacting with animals can provide relief for people suffering from depression and mood disorders. This is evidenced by a number of studies from the last twenty years. In 1996, scientists investigated how tetrapods affect the mood of elderly people. It turned out that a weekly contact with the “visiting” dog was enough for the residents of the nursing home to experience an improvement in mood and well-being. The presence of a resident dog in other centers of this type brought similar effects. A 2002 study found that contact with animals helps reduce the feeling of loneliness in the elderly. Interestingly, the mood is improved not only by the presence of tetrapods, but also of birds – especially direct contact with them, for example, stroking – which is confirmed by a study from 1996. According to other studies, contact with animals alleviates the symptoms of patients with schizophrenia. Dog therapy, which helps to deal with emotional problems, also has proven health effects.

Dog and cat owners are less likely to suffer from cardiovascular disease. And when they get sick – they have a better chance of survival. According to a 1995 study in the American Journal of Cardiology, dog owners who have suffered a heart attack are much less likely to die in the following year than those who live without pets. In the study group, out of 87 “dogs”, only one death was recorded, while out of 282 people without animals, as many as 19 died within twelve months after the heart attack. Social support also plays an important role in recovery. Like contact with dogs, it increases life expectancy after MI, regardless of other psychosocial and even physiological factors. According to a 2009 meta-analysis, dog owners are less likely to develop heart disease by having to … take their pets out for a walk on a regular basis, which is moderate but regular exercise.

Animals can benefit the human immune system. Or at least dogs – as confirmed by a study published in 2004 in the journal Psychological Reports. 55 college students who were randomly assigned to one of three groups took part in the experiment with the quadrupeds. 19 people from the experimental group were supposed to pet the dog. 17 people from the first control group did the same – only that the object of their caress was a dummy animal. In the second control group there were 19 people who sat comfortably but idly on the couch. Saliva samples were collected from participants before and after the 18-minute experiment. It turned out that people playing with living creatures had a marked increase in the level of immunoglobulin A (IgA) – a compound responsible for the immune response. IgA plays an important role in the immune response in the respiratory tract, gastrointestinal mucosa, and the genitourinary system. This substance prevents, inter alia, colonization of the organism by pathogenic pathogens.

This is not a surprise for animal lovers, although it’s nice to know that this fact is confirmed by research. An experiment carried out in 2003 showed that playing with a dog reduces the level of cortisol and increases the concentration of oxytocin, dopamine, prolactin, endorphins and phenylalanine. The first of these compounds is the stress hormone, which has a similar effect on human metabolism to that of adrenaline. The persistently elevated level of this substance in the blood causes a number of adverse health consequences, such as the development of obesity, insulin resistance, and skin inflammations. The other compounds are neurotransmitters, the action of which is related, inter alia, to with the improvement of mood. In addition, they perform many other important functions in our body, including regulate blood pressure, appetite, and the work of the nervous system. A study from 2010 showed similar results. It showed that in children with autism spectrum disorders, the level of cortisol, and thus stress, decreased as a result of interactions with dogs. This is significant because chronic nervous tension is considered one of the main risk factors for the development of civilization diseases, such as heart disease, diabetes and cancer.