I’d like to publicly thank my older sisters for bringing home plenty of germs and leaving me relatively allergy free. According to research, there’s “something about being the youngest that was protective. And it’s probably the same theory that you’re just getting exposed to more germs on a day-to-day basis, and that, at a young age, that’s actually helpful because it helps to train your immune system so it’s not going to be oversensitive when the kid gets a little bit older.” NPR: Why our allergies are getting worse —and what to do about it. “If it seems like your seasonal allergies are getting worse over time, you’re probably not wrong. Estimates are that 30 to 40% of the world’s population now have some form of allergy, and medical anthropologist Theresa MacPhail says allergic reactions — including everything from hay fever to eczema and asthma — are growing in the U.S. and around the world.”