People with contact allergies develop reactions when they touch chemicals and common metals such as nickel.
A new Danish study looked at nearly 17,000 adults who were tested for contact allergies between 1984 and 2008. They found both men and women with contact allergies had significantly lower rates of breast and non-melanoma skin cancer.
Women with contact allergies also had lower rates of brain cancer.
However, people with contact allergies had higher rates of bladder cancer.
They study is published in the online edition of the journal BMJ Open.