What You Need to Know about Breast Cancer and Hair Dye
What Are the Risk Factors for Breast Cancer?
Studies have shown that your risk for breast cancer is due to a combination of factors. The main factors that influence your risk include being a woman and getting older. Most breast cancers are found in women who are 50 years old or older.
Some women will get breast cancer even without any other risk factors that they know of.
Having a risk factor does not mean you will get the disease, and not all risk factors have the same effect. Most women have some risk factors, but most women do not get breast cancer. If you have breast cancer risk factors, talk with your doctor about ways you can lower your risk and about screening for breast cancer.
Risk Factors You Cannot Change
Getting older. The risk for breast cancer increases with age; most breast cancers are diagnosed after age 50.
Genetic mutations. Inherited changes (mutations) to certain genes, such as BRCA1 and BRCA2. Women who have inherited these genetic changes are at higher risk of breast and ovarian cancer.
Reproductive history. Early menstrual periods before age 12 and starting menopause after age 55 expose women to hormones longer, raising their risk of getting breast cancer.
Having dense breasts. Dense breasts have more connective tissue than fatty tissue, which can sometimes make it hard to see tumors on a mammogram. Women with dense breasts are more likely to get breast cancer.
Personal history of breast cancer or certain non-cancerous breast diseases. Women who have had breast cancer are more likely to get breast cancer a second time. Some non-cancerous breast diseases such as atypical hyperplasia or lobular carcinoma in situ are associated with a higher risk of getting breast cancer.
Family history of breast cancer. A woman’s risk for breast cancer is higher if she has a mother, sister, or daughter (first-degree relative) or multiple family members on either her mother’s or father’s side of the family who have had breast cancer. Having a first-degree male relative with breast cancer also raises a woman’s risk.
Previous treatment using radiation therapy. Women who had radiation therapy to the chest or breasts (like for treatment of Hodgkin’s lymphoma) before age 30 have a higher risk of getting breast cancer later in life.
Women who took the drug diethylstilbestrol (DES), which was given to some pregnant women in the United States between 1940 and 1971 to prevent miscarriage, have a higher risk. Women whose mothers took DES while pregnant with them are also at risk.
Risk Factors You Can Change
Not being physically active. Women who are not physically active have a higher risk of getting breast cancer.
Being overweight or obese after menopause. Older women who are overweight or obese have a higher risk of getting breast cancer than those at a normal weight.
Taking hormones. Some forms of hormone replacement therapy (those that include both estrogen and progesterone) taken during menopause can raise risk for breast cancer when taken for more than five years. Certain oral contraceptives (birth control pills) also have been found to raise breast cancer risk.
Reproductive history. Having the first pregnancy after age 30, not breastfeeding, and never having a full-term pregnancy can raise breast cancer risk.
Drinking alcohol. Studies show that a woman’s risk for breast cancer increases with the more alcohol she drinks.
Research suggests that other factors such as smoking, being exposed to chemicals that can cause cancer, and changes in other hormones due to night shift working also may increase breast cancer risk.
What You Need to Know about Breast Cancer and Hair Dye
We already know many risk factors(above) for developing breast cancer.
There are those you can’t change, such as s3x, age, and genetics.
There are some you can change, like sedentary lifestyle and alcohol consumption.
Whether or not you develop breast cancer is likely not due to a single thing but a combination of factors. One of those factors may be exposure to certain chemicals.
Chemical hair dyes and straighteners contain more than 5,000 chemicals, say the authors of a new study published in the International Journal of Cancer.
Researchers at the National Institute of Environmental Health Sciences, part of the National Institutes of Health (NIH), looked at chemical hair dyes and straighteners to see if they’re linked to increased breast cancer risk.
They say their study supports the theory that women who use permanent hair dye and chemical hair straighteners have a higher risk for developing breast cancer than those who don’t.
The rise in risk was lower for women who have their hair done in a salon. Using semipermanent or temporary dye was associated with little to no increase in risk.
Experts say there’s a lot to learn from this study, but they caution that it doesn’t prove cause and effect.
The researchers used data from 46,709 women who enrolled in the Sister Study between 2003 and 2009.
Participants were between the ages of 35 and 74 and came from all 50 states and Puerto Rico. None had a personal history of breast cancer, but all had a sister with a breast cancer diagnosis.
The researchers factored in such variables as socioeconomic status, reproductive history, and menopausal status.
Average length of follow-up was 8.3 years.
Study participants who used hair dye tended to be younger, have fewer years of education, were more likely to be current smokers, and more likely to have used oral contraceptives.
Black women, postmenopausal women, and those who had fewer children were less likely to have used permanent dye.
As a whole, women who regularly used permanent hair dye in the year before enrolling in the study were 9 percent more likely to develop breast cancer than those who didn’t use these products.
For black women, the increase was 45 percent, while it was 7 percent for white women.
According to the researchers, products marketed to black women have higher concentrations of estrogens and endocrine-disrupting compounds.
The use of permanent dyes every 5 to 8 weeks or more was associated with a 60 percent increased risk of breast cancer for black women. The increase in risk was about 8 percent for white women.
Overall, using chemical straighteners in the year before enrollment was associated with an 18 percent increase in risk.
The researchers found that women using hair straighteners every 5 to 8 weeks were about 31 percent more likely to develop breast cancer. The association was about the same for black and white women, but more black women used straighteners.
Study authors wrote that the research highlights “potential differences in associations by ethnicity” and the findings “have the potential for substantial public health impact.”
What the study doesn’t tell us
Dr. William J. Gradishar is a professor of breast oncology, director of the Maggie Daley Center for Women’s Cancer Care, and director of Breast Medical Oncology at Robert H. Lurie Comprehensive Cancer Center at Northwestern University in Illinois.
Gradishar told Healthline that the study’s conclusions were based on a large number of participants. That’s a positive element.
“But as usual with survey data, when asking what patients did or did not do, or what they were exposed to, there’s always a risk of having some error in recall,” he said.
“None of the women got genetic testing, so we don’t know if they were at higher risk. Some probably were, which might explain some of the observations made,” Gradishar said.
Gradishar, who chairs the National Comprehensive Cancer Network (NCCN) Guidelines Panel for Breast Cancer, says it’s difficult to know whether these observations are applicable to the broader population.
“We don’t want to dismiss these results, but one has to be cautious about overinterpreting them,” Gradishar said.
Study authors acknowledged they didn’t evaluate the formulation of the various dyes or straighteners used. Use of hair products throughout the follow-up period wasn’t considered.
Dr. Stephanie Bernik is the chief of Breast Service at Mount Sinai West and an associate professor of surgery at the Icahn School of Medicine at Mount Sinai in New York.
“I’m not surprised at a potential connection between hair dye and breast cancer,” she told Healthline. “There are chemicals in dyes that act as estrogen disrupters and other chemicals that are carcinogenic.”
Bernik doesn’t have absolute confidence that hair products are the reason study participants developed breast cancer.
“It was a select group of women. Every participant had a sister with breast cancer, so they already had elevated risk,” she explained.
“Many things we once held to be true about breast cancer risk turned out not to be the case. The bottom line is that more studies should be done to prove it. This one indicates that it may increase breast cancer risk, not that it does,” Bernik said.
Should women stop using hair products?
Gradishar suggests that women shouldn’t be overly concerned or necessarily stop using hair products based on this study alone.
“We need to be cautious about scaring everybody,” he said.
Bernik advises women to be careful when using permanent hair dyes or straighteners at home. Use gloves and follow package safety warnings.
For those who are worried or fall into high-risk groups, she recommends looking at alternatives, such as using semipermanent dye or going to a salon.
While white women who dyed their hair regularly face a 7% chance of developing, black women face a much higher risk – 45%.
Our new work is out today- we found permanent hair dye and chemical straightener use was associated with higher risk of breast cancer #epitwitter #AcademicTwitter #sisterstudy #breastcancer https://t.co/2Z5FdiEfIo
— Alexandra White (@alexandrajwhite) December 4, 2019
Putting risks into perspective
According to the American Cancer Society, the average lifetime risk of developing breast cancer is 13 percent for women in the United States. It’s less common than skin cancers.
The higher risk for black women is something we’ve known for a long time, says Gradishar.
In particular, black women have a greater frequency of triple-negative breast cancer.
“There are a lot of individual things we’ve known for decades that contribute to elevated risk, and perhaps this [dyes and straighteners] will be another. But none exist in isolation,” he said.
Gradishar advises all women to get screening mammograms as recommended.
Bernik says that if you’re concerned about breast cancer risk, a low fat diet and regular exercise go a long way.
“Previously we have found that if you lead a healthy lifestyle, you’re less likely to get cancer. That’s really proven,” she said.