MORE ON THE PARASITE / ALLERGY HYPOTHESIS: “People know that something isn’t right. They keep their kids in the cleanest environments and they get asthma. We get all of these things that were rare becoming common. And a lot of it comes down to hygiene. Excessive hygiene can potentially lead to disease.” D’oh! Plus, the advantages of letting your kids play in the dirt, and the big, big question: “Will people be afraid to take a worm pill?”