Allergies have become a widespread in developed countries: hay fever, eczema, hives and asthma are all increasingly prevalent. The reason? Excessive cleanliness is to blame according to Dr. Guy Delespesse, a professor at the Université de Montréal Faculty of Medicine.

Allergies can be caused by family history, air pollution, processed foods, stress, tobacco use, etc. Yet our limited exposure to bacteria concerns Dr. Delespesse, who is also director of the Laboratory for Allergy Research at the Centre hospitalier de l'Université de Montréal.

"There is an inverse relationship between the level of hygiene and the incidence of allergies and autoimmune diseases," says Dr. Delespesse. "The more sterile the environment a child lives in, the higher the risk he or she will develop allergies or an immune problem in their lifetime."

In 1980, 10 percent of the Western population suffered from allergies. Today, it is 30 percent. In 2010, one out of 10 children is said to be asthmatic and the mortality rate resulting from this affliction increased 28 percent between 1980 and 1994.

"It's not just the prevalence but the gravity of the cases," says Dr. Delespesse. "Regions in which the sanitary conditions have remained stable have also maintained a constant level of allergies and inflammatory diseases."

"Allergies and other autoimmune diseases such as Type 1 diabetes and multiple sclerosis are the result of our immune system turning against us," says Dr. Delespesse.

Why does this happen? "The bacteria in our digestive system are essential to digestion and also serve to educate our immune system. They teach it how to react to strange substances. This remains a key in the development of a child's immune system."

Although hygiene does reduce our exposure to harmful bacteria it also limits our exposure to beneficial microorganisms. As a result, the bacterial flora of our digestive system isn't as rich and diversified as it used to be.

Dr. Delespesse recommends probiotics to enrich our intestinal flora. Probiotics are intestinal bacteria that have a beneficial impact on health. They've been used for decades to make yogurt. Probiotics have a proven effect on treating diarrhea, and studies are increasingly concluding similar benefits for the immune system and allergies.

"Consuming probiotics during pregnancy could help reduce allergies in the child," says Dr. Delespesse. "They are not a miracle remedy, yet they are one of many elements that improve our diet and our health."

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