These Six Things Don't Actually Cause Cancer

Cancer doesn’t have a cause, and no one has the right to suggest your actions might have led to cancer. Here’s what the science says about common cancer correlations.

Did something I did or didn’t do cause cancer? A decade ago, when I was diagnosed with breast cancer at 42, I questioned everything in my life.

I tried to make sense of it, and I went straight down the proverbial rabbit hole.

Was it the cellphone I had tucked in my underwire bra or the antiperspirant I used? Maybe it was all that microwave popcorn I ate, or using plastic everything, or dying my hair.

To this day, some people will ask me if I use antiperspirants and microwaves — as if I caused my own cancer.

Where did these cancer myths come from? Read on to learn how they got started, plus the research that proves them wrong.

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1. Underwires: uncomfortable, but not all-powerful

Myth: Underwire bras may block lymph flow and contribute to toxic buildup in the underarm area, leading to breast cancer.

The reality: There’s no clinical or scientific evidence to support the rumors that underwire bras lead to breast cancer.

This idea may have come from a 1995 book called “Dressed to Kill: The Link Between Breast Cancer and Bras,” which claimed that women have a much higher risk of breast cancer if they wear underwire bras for more than 12 hours a day.

In the only study conducted on bra-wearing and cancer was conducted 20 years after the book was released. Researchers studied 1,513 women ages 55 to 74 years and found no association between bra-wearing and breast cancer.

Researchers considered factors including:

• cup size
• how recently a bra was worn
• hours worn per day
• underwire use
• age participant started wearing bras regularly

2. Antiperspirant: don’t sweat it

Myth: Chemicals from antiperspirants accumulate under the arms and in the breast tissue, causing cancer.

The reality: There’s no strong scientific evidence to support a link between breast cancer and antiperspirant use.

Before viral social media posts, there were viral emails in the 90s. The infamous myth that antiperspirants contribute to breast cancer may have begun in one of these emails.

This urban legend claimed that if you nicked your armpit shaving, chemicals from your antiperspirant could get into your body and cause cancer. I’ve actually been vaguely aware of this myth since long before my own diagnosis.

The only studies showing any kind of link between cancer and antiperspirants are considered unreliable.

Additionally, a 2021 study comparing 384 people with breast cancer and an equal number without breast cancer found no significant link between aluminum-based antiperspirants and breast cancer.

3. Hold the phone on cell phones and cancer

Myth: Cell phones cause breast cancer, especially if you put them in your bra.

Reality: The risks of cellphone use aren’t fully understood, but there’s no definitive evidence that they cause cancer — or any other health problems.

Have you ever used your bra as a convenient “pocket” to tuck your cellphone into? Somewhere along the way, the myth surfaced that doing this could cause breast cancer.

This idea likely came about following the belief that holding a cellphone to your head could cause brain tumors. However, a 2024 review conducted by the World Health Organization (WHO) found no evidence that mobile phone use causes brain cancer.

According to the FDA, there’s insufficient evidence of health problems caused by exposure to radio frequency energy emitted by cell phones.

The CDC’s stance? “There is no scientific evidence that provides a definite answer to the question, and more research is needed.”

4. When prevention gets a bad rap: mammograms and cancer

Myth: Mammograms meant to catch cancer early can actually cause it.

The reality: This myth is harmful because it may prevent people from getting lifesaving screenings. In most cases, the potential benefits of getting mammograms far outweigh the potential harm.

Some people fear that the radiation involved in screening for cancer actually might cause it.

There is radiation involved in mammograms and X-rays, and we’re exposed to natural and manmade sources of radiation every day. Repeated exposure to radiation can increase the risk of cancer.

However, the potential benefits of getting mammograms almost always outweigh the potential harm from radiation exposure. However, if you’re concerned about your own levels of exposure, talk with your doctor.

5. The verdict on microwaves: enjoy your popcorn

Myth: Microwaves emit cancer-causing waves.

The reality: The FDA limits the amount of microwaves that can leak from an oven throughout the device’s lifetime to 5 milliwatts (mW), which is far below the level known to harm people.

Microwave ovens are constructed to prevent the escape of electromagnetic radiation. This includes safety interlocks that ensure the oven turns off anytime the door is opened.

6. Hair dye: go blonde if you want to

Myth: Exposure to hair dye causes cancer.

The reality: The International Agency for Research on Cancer (IARC) concluded that workplace exposure to hair dye could be carcinogenic, but that personal hair dye isn’t a risk factor.

According to Cancer.org, it’s not clear how much personal hair dye use could raise cancer risk, if at all. Most studies have not found a strong link between hair dye and cancer, but there’s a need for more research.

When myths have some merit

While a lot of the myths out there are just plain false, some of the rumors about cancer-causing substances have some research behind them.

Plastic and BPA

Most of the research on plastic and BPA involves animal or cell studies.

For instance, a 2021 review noted that BPA has been shown to induce the growth of breast, prostate, and ovarian cancer cells in test tubes. It also noted that exposure to BPA early in life was linked to increased rates of breast and prostate cancer in animals.

One 2021 study found higher BPA concentrations in urine and breast adipose tissue samples of people with breast cancer compared to people without breast cancer.

Another 2021 study found a link between BPA and prostate cancer, but not breast cancer.

Parabens

The FDA notes that there’s currently no information showing that parabens used in cosmetics have an effect on human health, but more research is needed.

According to a 2023 study, healthy participants who reduced their use of personal care products with parabens and phthalates showed reductions in cancer-related biomarkers.

A 2022 review noted that paraben exposure can increase the presence of cancer-generating cells.

So what actually increases breast cancer risk?

In my 10 years in Cancerland, I’ve seen people who were the picture of health and wellness and those who weren’t both get breast cancer. It’s impossible to know why it happens to an individual person.

That said, the CDC notes there are certain risk factors for breast cancer that can’t be changed. These include:

Age and gender

The risk of breast cancer increases as people age, and women are more likely to get it. Most cases are found in women over 50.

Genes and family history

Certain genes, like BRCA1 and BRCA2, raise the risk of getting breast cancer. If you have close relatives with breast or ovarian cancer, it also increases your chances.

Hormones and reproductive factors

Starting your periods before age 12 or experiencing menopause after 55 can increase the risk of breast cancer due to increased exposure to hormones.

Breast characteristics

Dense breasts make it harder to spot tumors, which may increase cancer risk.

Personal health history

Women who’ve already had breast cancer or certain noncancerous breast conditions are at higher risk.

Previous treatments

Chest radiation therapy earlier than age 30 can raise the risk of breast cancer later in life.

How to spot sensationalist cancer claims

There’s so much information floating around online and on social media claiming this or that about cancer.

When learning new information, I look at who is sharing it. Is it a social media influencer trying to rack up likes, or somebody who can back up information by citing sources and studies?

Whenever you come across new health information, put on your critical thinking hat. Start off with a skeptical eye until you’re able to verify the information from a reliable source.

Ultimately, the best place to start with questions and concerns is a doctor or oncologist who knows your personal health history.

Takeaway

Just remember, cancer happens.

You didn’t cause your cancer by putting your cellphone in your underwire bra while putting on antiperspirant, before your mammogram appointment, after eating microwave popcorn.

Do your own homework by talking with your doctors and finding reliable sources for cancer information.

And remember: Do what you can when you can. Otherwise, don’t sweat the small stuff.