Breast cancer is a major cause of cancer-related deaths among women. According to a new finding, the use of permanent hair dyes and straighteners can increase the risk of this chronic disease, especially in African American women.

The study that was published in the International Journal of Cancer on Wednesday suggested that black women are more likely to develop this deadly disease due to their use of hair dyes and straighteners than their white counterparts. Over two million women worldwide are affected by breast cancer every year. According to the World Health Organisation (WHO), it is a major cause of cancer-related deaths among women with around 15 percent of deaths caused due to it.

Breast cancer
Over two million women worldwide are diagnosed with breast cancer every year. Pixabay

What is Sister Study?

For the research, the study team examined data of an ongoing study called the Sister Study, which involved nearly 46,800 women between the age group of 35 and 74. Around nine percent of the participants were African American women. The research began by analysing the lifestyle surveys and medical records of each of the participants. The study team, then, asked the participants to file up a questionnaire with details about their use of hair dyes and straighteners.

At the end of the study, the researchers found that those who used permanent hair dyes or chemical straighteners were at increased risk of developing breast cancer later in life. The study team also found that black women had a 45 percent increased risk of developing this chronic disease than their white counterparts.

"Researchers have been studying the possible link between hair dye and cancer for a long time, but results have been inconsistent. In our study, we see a higher breast cancer risk associated with hair dye use, and the effect is stronger in African American women, particularly those who are frequent users," Alexandra White, corresponding author and head of the National Institute of Environmental Health Sciences (NIEHS), said in a statement.

Which chemical can cause breast cancer?

A limitation of the study is that it was not designed to find out which chemical in permanent hair dyes and straighteners can cause breast cancer. The research did not look into the specific ingredients contained in the products used by the study's participants.

Another limitation is that all the participants in the study were already at risk of developing breast cancer as their sisters had this chronic disease. "We are exposed to many things that could potentially contribute to breast cancer, and it is unlikely that any single factor explains a woman's risk. While it is too early to make a firm recommendation, avoiding these chemicals might be one more thing women can do to reduce their risk of breast cancer," Dale Sandler, co-author of the study, said in a statement.