July 4, 2006

European study supports hair dye-lymphoma link

NEW YORK (Reuters Health) - Using hair dye may increase the
risk of a type of cancer known as lymphoma, a European study

"Our data suggest that personal use of hair coloring is
associated with a small increase in lymphoma risk, particularly
among women who started using hair coloring products before
1980," Dr. Silvia de Sanjose of the Catalan Institute of
Oncology in Barcelona and colleagues write in the July 1 issue
of the American Journal of Epidemiology.

Past research has suggested a link between coloring one's
hair and lymphoma risk, de Sanjose and her team note. They
sought to investigate the association by analyzing results from
a large study of lymphoma patients and matched healthy
controls, including a total of 4,719 people from six European
countries. About three quarters of women reported using hair
dye, while 7 percent of men did.

The researchers found an overall 19 percent increased risk
of lymphoma among people who reported coloring their hair. The
increased risk was 26 percent among those who used hair dye 12
or more times a year.

People who began coloring their hair before 1980 showed a
37 percent increased lymphoma risk, while those who had only
dyed their hair before 1980, but not afterwards, showed a 62
percent increased risk.

Based on the findings, de Sanjose and her team calculate
that roughly 10 percent of lymphomas in women could be due to
the use of hair dye.

From 1978 to 1982, the researchers note, the ingredients of
certain types of dyes were changed to eliminate some
potentially cancer-causing agents. But it is not clear whether
the newer dyes are risk-free. Clearly, more research is needed,
they conclude.

SOURCE: American Journal of Epidemiology, July 1, 2006.