I have been following this line closely since I have some pretty bad allergies and have had since a child. I grew up in a poor family in the late forties and early fifties. Making mud pies, cats, dogs, four siblings, neighbors all over the place, exposed to everything that came along and had most of the childhood illness's as there weren't any vaccines in those days. In other words I wasn't sheltered, protected or in a "clean" enviriorment. What is even more interesting is that for a little over two years I had been symptom free for the most part...then this last year started lo-carb diet and have been moving in the direction of paleo although not there by a long shot - and for the last month have had the worst episode of sinus allergies and asthma attacks that I have had in years...figure that one out! My wife thinks my diet is causing it. My doctor says allergies are allergies and there is no predicting when and where and how intense the attack will be. Me, I am just glad I have an inhaler so I can survive. steve