I had terrible allergies pre diet change. I was on a CW diet that I learned from my nutrition courses at school. I also was involved in a lot of chronic cardio. I was taking immuno therapy shots for allergies twice a week for a year and it really didn't help. And it was super expensive.
Since starting paleo over a year ago things have changed big time. Removing gluten/dairy from the diet helped the most. As well as slowing down with my exercises and sleeping better. I haven't been sick in over a year and I no longer take shots or anti-histamines. On high pollen days I still get clogged up if its windy but so does everyone else I work out with who don't have a history of allergies. If you ever get congestion in the sinuses and good fix is to use a neti pot which works wonders. I also agree that a good D3 supplement is a key component if you are not getting adequate sun exposure.
"If man made it, don't eat it" - Jack Lallane
People say I am on a "crazy" diet. What is so crazy about eating veggies, fruits, seafood and organ meats? Just because I don't eat whole wheat and processed food doesn't make my diet "crazy". Maybe everyone else with a SAD are the "crazy" ones for putting that junk in their system.