When I lived in Portland I was miserable in late spring because the grass pollen levels would go through the roof there. It is a consequence of being in a valley were 80–90% of the world’s grass seed is raised, and lawn grasses in general ranking high on the list of allergenic pollens. Friends kept recommending this or that alternative medicine treatment to me, but the only thing that really helped was getting out of Portland. As soon as I left, springtime allergies went back to being a minor annoyance instead of a major deal.
Ragweed pollens are the other big allergens on my list, but ragweeds are not very common on the West Coast (we have only one species in this region, and it’s quite particular about where it grows, so there just isn’t very much of it). It’s a big part of why I refuse to consider moving to the eastern half of the continent.
The experts caution against trying to solve one’s allergy problems by moving, but it’s the one thing that’s really worked for me. (It’s worked in reverse, too; the times I’ve moved to the Midwest and the Willamette Valley, allergies went from being something minor to something major and life-impacting almost immediately.)
That said, many of the food sensitivities I have are linked to certain foods having proteins in them similar to pollen allergies I have.