Put away the hand sanitizer. It's not necessarily the grime, dust bunnies, cat dander, or pollen causing those miserable springtime allergies. The culprit actually may be too much cleanliness.
"Allergies have become widespread in developed countries: Hay fever, eczema, hives, and asthma are all increasingly prevalent. The reason? Excessive cleanliness is to blame," said Dr. Guy Delespesse, an immunologist and director of the Allergy Research Laboratory at the University of Montreal.
While family history, air pollution, processed foods, stress, and other factors can trigger allergic reactions, Delespesse is concerned by "our limited exposure to bacteria" — even cautioning parents to lighten up when their children drop toys on the floor.
"There is an inverse relationship between the level of hygiene and the incidence of allergies and autoimmune diseases," he said. "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."
The sneezing, itching, and coughing is widespread.
Some 50 million Americans suffer from allergic conditions, and the numbers are increasing, according to the American Academy of Allergy, Asthma & Immunology. The cost of treating allergies and asthma stands at about $32 billion a year.
And there is much misery: 60 percent of allergy sufferers say they were unable to find ways to stamp out the seasonal ills, according to a survey released this week by Consumer Reports National Research Center.
Delespesse also frets about the burgeoning allergic population. He noted that 10 percent of people in developed countries suffered from allergies two decades ago. Today, the percentage has increased threefold to 30 percent, with one in 10 children suffering from asthma. Deaths from that condition are also increasing, he said.
"It's not just the prevalence but the gravity of the cases," Delespesse added.
Well-intentioned hygiene can backfire, particularly with youngsters.
"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," Delespesse explained. "This remains a key in the development of a child's immune system."
Cleanliness does reduce our exposure to harmful bacteria, he said. But 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 in less-paranoid times.
As a homestyle panacea, Delespesse recommends yogurt — which contains its own spate of microorganisms, or probiotics — "to enrich intestinal flora," and consequently the immune system itself.
"Consuming probiotics during pregnancy could help reduce allergies in the child," he said, adding that some studies found that women who ate yogurt in the last third of their pregnancy may reduce the impact of allergies during the first two years of their child's life by 50 percent.
"Probiotics are not a miracle remedy, yet they are one of many elements that improve our diet and our health," he said.