Could certain hair dyes, relaxers raise breast cancer risk?

June 21, 2017 by Randy Dotinga, Healthday Reporter

(HealthDay)—The safety of hair products has been debated for years. Now, new research suggests that black women who use dark hair dyes face a higher risk of breast cancer, while chemical relaxers and straighteners boost the odds in white women.

The findings stem from a study of more than 4,000 . Use of dark brown or black hair dyes by was tied to a 51 percent greater risk of breast . And whites who used hair relaxers had 74 percent higher odds.

But while the study found a possible link between the hair products and breast cancer risk, it did not prove a connection.

"Our findings do not suggest that simply using hair dyes, relaxers or both will cause a woman to get breast cancer," cautioned study lead author Adana Llanos.

"The reality is that we regularly encounter a variety of harmful exposures, which we have no control over," said Llanos, an assistant professor of epidemiology with the Rutgers School of Public Health and Rutgers Cancer Institute of New Jersey.

However, she added, "we should limit or reduce the possibility of harmful exposures when we are able to do so."

But another expert said the study findings are inconclusive and don't warrant a change in hair care.

Scientists have studied the potential risks of hair dye for decades, focusing on bladder cancer, leukemia and breast cancer. There haven't been any definitive findings yet. The American Cancer Society says most studies looking into hair dye and breast cancer have found no link between the two.

However, studies generally haven't included black women, Llanos said.

For the new study, researchers asked 4,285 white and black women in New York City and New Jersey about their past use of hair care products. Their ages ranged from 20 to 75. Nearly 2,280 were .

The idea was to compare hair product use among women who developed breast cancer and women who didn't get the disease.

The products included dyes, chemical relaxers and deep conditioning creams containing cholesterol or placenta. Cholesterol is marketed as a moisture restorer, and placenta is sold as a hair repairer, Llanos said.

While the study found that black women who used dark dyes had a 51 percent greater risk of developing breast cancer overall, the risk for developing estrogen receptor positive breast cancer—the most common type—was 72 percent higher.

Llanos said it's not clear why the chemicals in hair products may boost cancer risk. But she said research has suggested it could have something to do with DNA damage or the body's absorption of harmful chemicals.

It's also not clear why the risks might differ by race or why darker dyes might be especially dangerous.

"One hypothesis is that the chemical composition of hair products marketed for and used among whites may differ from the products marketed for use by African-Americans," Llanos said. "More research is needed to determine specifically which compounds and chemicals are dangerous and even which specific consumer products and brands contain those chemicals."

The researchers adjusted their findings so they wouldn't be thrown off by factors like age, education or use of birth control pills. And Llanos said it's possible that something related to lifestyle other than use of hair products could affect .

A toxicologist for the Personal Care Products Council, a trade group, countered that no studies have shown that hair dyes or relaxers cause cancer.

"Those who use cosmetics and personal care products can feel confident that they are protected by a combination of strong federal safety regulations enacted by the U.S. Food and Drug Administration [FDA] and the science-based safety assessments from the companies that manufacture these products," Linda Loretz, chief toxicologist for the council, said in a statement.

According to the U.S. National Cancer Institute, about 12 percent of American women will develop cancer at some point in their lives.

Although the study didn't include men, Llanos said her advice is the same for both sexes: "Be mindful of hair products, cosmetics and other that you use."

However, Dana Rollison, of the Moffitt Cancer Center in Tampa, Fla., said women shouldn't panic based on these results.

"Until more results are available, women should not be concerned with using ," said Rollison, who is vice president and chief data officer. "Exposures should not be avoided on the basis of a single study."

While the study tackles an important research question, Rollison said, it also has a number of limitations. She believes more research is needed to fully understand if there's a link between dye and .

The study appears in the June online issue of the journal Carcinogenesis.

Explore further: Hormonal contraceptives and hair dyes increase breast cancer risk

More information: Adana Llanos, Ph.D., MPH, assistant professor, epidemiology, Rutgers School of Public Health and Rutgers Cancer Institute of New Jersey, New Brunswick; Dana Rollison, Ph.D., vice president and chief data officer, department of cancer epidemiology, Moffitt Cancer Center, Tampa, Fla.; Linda Loretz, Ph.D., chief toxicologist, Personal Care Products Council; June 2017, Carcinogenesis

For more about hair dye and cancer, visit the American Cancer Society.

Related Stories

Hormonal contraceptives and hair dyes increase breast cancer risk

March 9, 2017
In her recent doctoral dissertation, researcher Sanna Heikkinen from the University of Helsinki and Finnish Cancer Registry evaluates the contribution of the use of hormonal contraceptives and hair dyes to the spectrum of ...

Pregnancy not dangerous for women who had breast cancer

June 4, 2017
Becoming pregnant after a diagnosis of breast cancer does not raise the risk of the cancer returning, said the largest study of its kind to date, released Saturday at a major cancer conference.

Are cooling caps the solution to prevent hair loss during chemotherapy?

March 15, 2017
Hair loss—one of the most-feared side effects of cancer treatment—may have met its match. Scientists have known since the 80s that cooling a person's scalp can prevent significant hair loss during chemotherapy. A cooling ...

Study confirms link between alcohol consumption, breast cancer risk in black women

May 1, 2017
Alcohol consumption is known to be a risk factor for breast cancer based on studies predominately done in white women. Now a University of North Carolina Lineberger Comprehensive Cancer Center study has found the same risk ...

Hair loss in women with breast cancer can have major implications on their sense of identity

April 19, 2016
A new study from The University of Nottingham highlights the importance of hair loss to women with breast cancer.

Researchers identify breast cancer risk factors for younger, black women

October 19, 2016
Black women under the age of 45 are at increased risk for an aggressive form of breast cancer [estrogen receptor (ER) negative] if they experienced a high number of pregnancies, never breast fed, and/or had higher waist-to-hip ...

Recommended for you

Targeting the engine room of the cancer cell

June 18, 2018
Researchers at Columbia University Irving Medical Center (CUIMC) have developed a highly innovative computational framework that can support personalized cancer treatment by matching individual tumors with the drugs or drug ...

Researchers create novel combination as potential therapy for high-risk neuroblastoma

June 18, 2018
Researchers at VCU Massey Cancer Center in Richmond, Virginia, have identified a promising target to reverse the development of high-risk neuroblastoma and potentially inform the creation of novel combination therapies for ...

Study suggests well-known growth suppressor actually fuels lethal brain cancers

June 18, 2018
Scientists report finding a potentially promising treatment target for aggressive and deadly high-grade brain cancers like glioblastoma. But they also say the current lack of a drug that hits the molecular target keeps it ...

Genomics offers new treatment options for infants with range of soft tissue tumors

June 18, 2018
The genetic causes of a group of related infant cancers have been discovered by scientists at the Wellcome Sanger Institute, the University of Wuerzburg and their collaborators. Whole genome sequencing of tumours revealed ...

Standard myelofibrosis drug can awaken 'dormant' lymphoma

June 18, 2018
Most patients with myelofibrosis, a rare chronic disorder of the haematopoietic cells of the bone marrow, benefit from drugs from the JAK2 inhibitor class: symptoms are relieved, survival extended and general quality-of-life ...

Breast cancer researcher warns against online genetic tests

June 18, 2018
We have never been so fascinated by the secrets inside our cells.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.