Hair Dye May Raise Cancer Risk
(Reuters Health,1/24/04)

Tongzhang Zheng of Yale School of Medicine, and team, compared 600 women who had non-Hodgkin lymphoma (NHL), a form of cancer that affects the lymphatic system, with 700 healthy women. The researchers report that subjects who began dying their hair before 1980, especially if they used dark permanent dyes, had a higher risk of developing NHL; whereas, those who had begun using hair coloring more recently did not have an increased risk. These findings indicate that either the removal of carcinogens from newer dye formulas has made them safer or that the cancer takes 25 years to manifest and these women may develop NHL at a future date.