6 breast cancer myths you shouldn’t believe

Can wearing underwire bras cause breast cancer? What about using antiperspirants containing aluminum or eating foods made with soybeans?  

The answer to all three of these questions is “no.” We went to Therese Bevers, M.D., medical director of MD Anderson’s Lyda Hill Cancer Prevention Center to understand why and further separate fact from fiction. Here, she debunks these and three more breast cancer myths that you shouldn’t believe. 

Myth 1: Wearing an underwire bra can cause breast cancer.

Fact: Underwire bras can be uncomfortable. But can that pinching sensation around your rib cage really lead to a breast cancer diagnosis? Bevers says no. 

“We don’t have any evidence to support that theory,” she says. “While breast cancers can develop in the lower inner and outer quadrants of the breast — the parts closest to the underwire — that’s not the most common location for them to occur. And cancer is not caused by a wire pinching or poking you anywhere.” 

So, why does this particular myth persist?  

“A lot of women find underwire bras painful,” Bevers notes. “And breast cancer is one of the most common forms of cancer. So, I suppose it’s normal to wonder if one causes the other. But it doesn’t. Pain isn’t a typical symptom of breast cancer, either. Most breast cancers are painless. So, if you want to wear underwire bras, go ahead. Unless you’re still healing from a mastectomy, we don’t advise against it for anyone.” 

Myth 2: Using antiperspirants that contain aluminum can cause breast cancer.

Fact: Many conventional antiperspirants contain some form of aluminum to block the sweat glands in the armpit temporarily. People have been using them now for more than a century. 

“But, again, we have no data to support the theory that these products cause cancer,” says Bevers. “If that were the case, we’d be seeing a lot more breast cancers in men, because they use antiperspirants, too. And, we haven’t.”  

Even if the aluminum in antiperspirants does turn out to be a risk factor someday, she notes, it would likely still be at a very, very low level. So, why does this myth persist? 

“When researchers found traces of aluminum in some breast tumors, people jumped to the conclusion that antiperspirants caused them,” Bevers explains. “But you can find traces of aluminum even in normal, healthy breast tissue. So, it’s not surprising that tumor tissue would contain it as well. That doesn’t mean the aluminum caused it. There’s a big difference between correlation and causality.” 

Myth 3: Eating soy products can cause breast cancer.

Fact: Soybeans contain phytoestrogen, a naturally occurring plant compound that is thought to mimic the effects of estrogen when ingested.  

Some breast cancers are fueled by hormones, so patients might fear that eating soy products could hinder their breast cancer treatments — or even encourage breast cancer to grow.   

But Bevers says not to worry. 

“First of all, it’s the combination of estrogen plus progesterone as a hormone replacement therapy that slightly increases your risk of breast cancer,” she explains. “Estrogen alone does not appear to do so. And second, some phytochemicals in soy products are known to be beneficial.” 

So, why does this myth persist? 

“I think it’s because how phytoestrogen affects the body is a question that has yet to be fully answered,” says Bevers. “I just tell my patients not to use soy supplements to try to relieve hot flashes or other symptoms of menopause; they’re not regulated in the same way that medicines are and they haven’t been proven effective. But there’s no need to avoid soy in general. It can still be part of a healthy diet.” 

Myth 4: Breast cancer always involves a lump.

Fact: You might think that breast cancer always involves a lump. But that’s not the case.  

“Inflammatory breast cancer (IBC) usually presents as a skin change,” says Bevers. “That can confuse people sometimes, so they’ll show up in my clinic with just a very small area of pink on their skin. I’m happy to work it up and tell them that it’s not IBC. But there’s usually no mistaking IBC for something else. It’s pretty dramatic.”  

Still, if you notice something about your breasts that’s unusual for you, Bevers says to get it checked out. 

“IBC is pretty rare,” she says. “But any time you have symptoms that are causing you concern, you should get them evaluated.” 

Myth 5: Breast cancer only occurs in women.

Male breast cancer makes up only about 1% of all U.S. breast cancer diagnoses each year. So, a lot of people don’t realize that men can get it, too. But they can. 

“It’s rare, but if a man feels a lump or notices discharge or changes in his breast, he should get checked out,” says Bevers. “I have several male breast cancer patients who were diagnosed with just those symptoms.”  

A genetic mutation such as BRCA1 or 2 — which increases your odds of developing breast cancer — can even be passed down through a father’s bloodline. So, don’t dismiss that as a possibility if a male in your family is diagnosed with breast cancer.  

“Any time I encounter a male with breast cancer, I wonder, ‘Why did he get this?’” says Bevers. “It’s not uncommon to find a genetic mutation in those cases.”  

Myth 6: Breast cancer is usually genetic.

Fact: Cancer touches so many people’s lives that it’s easy to become convinced it must be passed down from generation to generation — especially if cancer runs in your family.  

Actually, the opposite is true. Between 90% and 95% of all cancers are not hereditary. 

“While breast cancer can be genetic, most women diagnosed with breast cancer do not have a family history of it,” Bevers says. “Women who do are obviously at higher risk, but the vast majority of breast cancers occur in women who have no genetic mutation.” 

So, why does this myth persist? 

“I think people hear how high the risk can be for cancer in individuals who do have a genetic mutation or a strong family history and somehow get that mixed up with the percentage of cancers that are caused by one,” says Bevers. “But that’s just a guess.” 

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