Olga Khazan on The Reason Anxious People Often Have Allergies:
“There is good circumstantial evidence that’s growing that a number of mental illnesses are associated with immune dysfunction,” says Sandro Galea, a physician and epidemiologist at the Boston University School of Public Health.
If the link is in fact real, allergies could be causing anxiety and other mood disorders in a few different ways. For one, it’s stressful to be sick, and people with allergies frequently feel like they have a bad cold. The experience of straining to breathe, or of coughing and wheezing, could simply make people feel anxious.
Then there are biological explanations. Allergies trigger the release of the stress hormone cortisol, which can interfere with a feel-good brain chemical called serotonin. It’s not clear how the cortisol does this, Nanda says; it might inhibit the production of serotonin or make it fail to bind with its receptors properly. But when something goes wrong with serotonin, the theory goes, depression or anxiety might set in.
Huh. I definitely suffer from seasonal allergies (they have thankfully slacked off for the summer) and have struggled with anxiety since I was a kid (though I’ve never been clinically diagnosed). I’ll be following this research with interest.