Hair dyes are as common as lipstick, with nearly as many shades. But some researchers say these popular beauty products have an ugly flip side: They may cause cancer. The Medical Detective asked experts, “Should she, or shouldn’t she?” Read on to learn the truth about coloring hair, where the harshest chemicals lurk and how to tone down gray the healthy way…
Coloring Hair Risk #1: The Type of Dye
More than 5,000 chemicals are in hair dye, according to the National Cancer Institute.
In 2004, the Environmental Working Group (EWG), a nonprofit environmental research and advocacy agency, rated 117 personal-care hair dyes, and found about 80 had chemicals that might pose a cancer risk. Today the group rates 945 hair dyes for safety at the EWG website.
Coloring Hair Risk #2: Frequency
The number of times you dye your hair may increase your cancer risk. Women who colored their hair with permanent dye at least once a month for a year or longer doubled their odds of developing bladder cancer over those who didn’t, according to a 2001 University of Southern California study.
Coloring Hair Risk #3: Your DNA
Your genetic makeup also may make you more susceptible to bladder cancer if you use permanent dyes, according to a 2011 study by the International Journal of Cancer.
Coloring Hair Risk #4: When You Started Dyeing
Started dyeing your hair before 1980? Then you have a 40% greater risk of Non-Hodgkin’s lymphoma, according to a 2008 combined analysis of four case-control studies that included more than 4,000 women with NHL and about 5,800 women without the disease.
That’s because earlier hair dyes contained chemicals such as aromatic amines, organic compounds joined to an aromatic structure that can harm your health. There was no increased risk among women who began using hair dye after 1980 because the FDA issued warnings about such chemicals and manufacturers dropped them from products.
Coloring Hair Risk #5: Pregnancy
Hair dyes probably are safe to use during pregnancy for both mom and fetus because absorption through the skin is minimal, according to the American College of Obstetricians and Gynecologists.
Still, pregnant women should think twice about coloring hair, especially with coal-tar-based products, Gago-Dominguez advises.