This was not all that surprising. Previous research had detected similar inverse correlations between allergies and brain tumours, suggesting that a welcome side effect of allergy was resistance to cancer. But this new study went further. It looked carefully at the time in the patients' lives when their allergies were active, and it found that this timing was crucial. Dr Wigertz noted that the absence of allergy was correlated with the time when a glioma first formed. That was true even in people who had previously had allergies which had then cleared up.
As an allergy sufferer, I never thought it was a good thing to have. It’s surprising how bad things could turn out to be good after all or have positive side effects. I guess it helps to remember this when something bad happens: despite the pain, it could prevent bigger suffering.