Why do more of us have allergies, asthma?

If you think that people are scratching, wheezing and sneezing more frequently, you're right. Worldwide, eczema, asthma, hay fever and food allergies have nearly doubled in the past 20 years, says Dr. Marc McMorris, clinical associate professor at University of Michigan and medical director of the university's allergy specialty and food allergy clinic.

By Anne Stein, Special to Tribune Newspapers

April 11, 2011