A recent study in Denmark may show that certain environmental allergies may protect us from cancer. The study indicated that allergies to nickel and other chemicals showed the greatest protection against breast and skin cancer (not melanoma).
The connection with allergies and cancer is not hard to understand. When we are exposed to an allergen, our immune system is on high alert, meaning we have a heightened immune response to many benign substances. People with primed immune systems may be more sensitive in detecting early cancer cells.
On the other hand, some people with contact allergies may be more likely to develop a higher risk of certain cancers. This study indicated that the risk for bladder cancer was more likely with those who had allergies vs non-allergic people.
More studies need to be done, but there seems to be an interesting link between environmnental allergies and cancer.