Habits in children that are often discouraged, such as thumb sucking and nail biting, may help prevent the development of allergies as children move into adulthood. A new study from the University of Otago in Dunedin, New Zealand concluded that children who develop habits that keep their hands and fingers near their mouths are exposed to microbes that reduce the risk of allergy development as they grow.
How Can Microbe Exposure Prevent Allergies?
Microbe exposure in children and adults causes an immune system reaction in which the body builds blood proteins that can identify and counter antigens. The proteins are called antibodies, and the more you have, the more diseases your body can fight on its own.
Strong evidence exists that suggests that in the first year of life, children who are exposed to microbes in dirt, dander, and other types of germs have a lower risk of developing allergies and asthma. These findings concluded that after the first year of life, the immune-boosting effects of microbes almost entirely lose efficacy. However, the Dunedin Multidisciplinary Study that has followed 1,037 patients for 40 years has brought to light incredible new evidence that contradicts the original finding.
In the study, children's nail biting and thumb sucking habits were recorded by parents at 5, 7, 9, and 11 years old. Following allergy testing by skin prick at ages 13 and 32 years old, researchers found that 38 percent of participants who had either sucked their thumb or bitten their nails had no allergies. The percentage is small compared to the 49 percent of children without oral nervous habits in childhood who suffered from at least one allergy. Even more impressive are that only 31 percent of participants who both sucked their thumb and bit their nails still developed allergies.
The results tell a promising but still inconclusive story. Though reactions to allergens were less prominent in thumb suckers and nail biters, the effect of nervous habits on allergic diseases such as asthma and hay fever seemed to be non-existent.
Should I Encourage My Child to Thumb Suck and Nail Bite?
Researchers say that it is best to avoid encouraging thumb sucking and nail biting habits in children. Rather, if your child is showing signs of an uncontrollable nervous habit, do not try to prevent him or her from continuing to partake in that habit. You may be depriving your child of microbes that help to train the body to fight diseases, allergies, and asthma.
The hygiene hypothesis suggests that the decrease in western countries of infectious disease has caused an increase in autoimmune and allergic disease. Some medical professionals believe that if a child is not given exposure to disease when he or she is very young, the child will become hypersensitive to viral and bacterial infections as well as increasing their risk for immune disorders in adulthood.
Accordingly, experts advise that parents allow their children to play and explore as freely as possible without putting them in danger. Exposure to outdoor conditions, soil, domesticated animals, and other substances that contain countless microbes may help your child develop an immune system that is prepared to handle the dangers among which he or she grows and prevent allergies.
