Infants with lower concentration of cortisol, the stress-related hormone, in their saliva develop fewer allergies than others, new Swedish research shows. Hopefully this new knowledge will be useful in future allergy prevention.
The study by Karolinska Institutet is published in the December paper issue of Journal of Allergy and Clinical Immunology.
The incidence of allergies in children has increased over the past few decades, especially in the West. In Sweden, 30 to 40 percent of children have some kind of allergy. A combination of environmental and lifestyle factors during pregnancy and early infancy are thought to be responsible for the sharp rise in allergic diseases.
"Psychosocial factors and the stress hormone cortisol are associated with allergic diseases," says Dr Fredrik Stenius of the Department of Clinical Research and Education at Stockholm South General Hospital. "Our study found that children with low salivary cortisol levels as infants have a lower prevalence of allergies during the first two years of life, compared to other children."
The team has previously described a link between a lower prevalence of allergies in school children and an anthroposophic lifestyle. Austrian scientist and philosopher Rudolf Steiner developed the anthroposophic lifestyle in which health is a combination of mind, body and spiritual balance; his followers integrate both modern medicine with alternative, nature-based treatments. They tend to make restrictive use of antibiotics and fever antipyretics
"And now we've found the same link in infants from families that follow anthroposophic lifestyles, and that they have relatively low levels of cortisol," adds Dr Stenius, who earned his PhD earlier in the year with a thesis on the subject.
The researchers believe that factors related to stress regulation also influence the development of infant allergies and will now monitor the infants from the neonate period and into childhood.