Do Antiperspirants Increase Breast Cancer Risk?

For decades, claims on the internet and offline have suggested that antiperspirants cause breast cancer. But research doesn’t show that using antiperspirants raises breast cancer risk.

Antiperspirants work by blocking pores on the skin, stopping sweat from getting to the surface. By blocking sweat, they can help stop your armpits from smelling.

Deodorants are different because they don’t affect how much you sweat. They only help fight body odor that develops from sweating.

Some of the chemicals in antiperspirants have been linked to cancer risk and other health issues. But the small amount of these chemicals you can absorb from antiperspirants hasn’t been shown to increase breast cancer risk. And deodorants don’t contain these chemicals at all, so deodorants are even less of a concern.

The main ingredient in antiperspirants that people worry about when it comes to breast cancer is aluminum. This metal is the active ingredient in antiperspirants that blocks pores and keeps you from sweating.

The worry with aluminum is that you could absorb it through the skin on your underarms, which are close to the breasts. If the metal gets in the body, some worry it’ll travel to the breasts and cause changes to estrogen receptors — for example, making them bind more estrogen. Estrogen can promote the growth of breast cells, including cancerous breast cells. So, some people worry that aluminum could increase breast cancer risk by increasing how much estrogen gets to breast cells.

There’s also evidence that aluminum inside the body may cause changes in a person’s genes and cells, which can increase cancer risk. 

But scientists don’t know how much aluminum actually gets through the skin and enters the body from antiperspirants. The amount may be very small — and maybe too small to increase cancer risk. A 2001 study, for example, found that only 0.012% of aluminum applied to underarms was absorbed. So, the amount of aluminum a person absorbs through the skin from antiperspirants would be much less than the amount a person absorbs through the gut from food during the same time period.

We’re exposed to aluminum through food, water, vaccines, and more. A 2023 study looked at lifetime exposure to aluminum from all sources. It found that, although more research is needed, there is not enough evidence to link breast cancer development to total aluminum exposure, let alone aluminum from antiperspirants.

Because deodorants don’t contain aluminum, they are not a concern for breast cancer risk.

The other main chemicals in antiperspirants that people worry about are parabens. These are preservatives that mimic estrogen and can be absorbed through the skin. Some research suggests that parabens have the potential to cause cancer. But studies of cancer in humans have not found evidence that it does, according to the American Cancer Society. And most antiperspirants and deodorants don’t contain parabens.

In addition to the chemicals found in antiperspirants, some people worry that stopping sweat could increase breast cancer risk by blocking cancer-causing toxins that leave the body through sweat. However, sweating is not how toxins leave the body. Rather, toxins leave the body through urine and feces.

Only a few studies have looked into possible links between antiperspirants and breast cancer.

Most of these studies have been case-control studies. In these studies, researchers ask a group of people with breast cancer and a group without it to report how often they have used antiperspirants during their lives. Because these studies ask people to think back decades ago, they aren’t very reliable. And people with breast cancer may be more likely to recall exposures to things that they think could be linked to cancer. So most of the research on this topic isn’t considered conclusive.

Even so, most case-control studies have not found a link between antiperspirants and breast cancer. They’ve found that both people who do have breast cancer and those who don’t are equally likely to have used antiperspirants.

More research with better study designs and more participants are needed to give a clearer sense of whether there is a link between antiperspirants and breast cancer. But for now, there’s no reason to believe that the two are connected.

Even though research hasn’t found a link between antiperspirants and breast cancer, there also isn’t a lot of strong research on the topic. So some experts recommend avoiding antiperspirants if you can, mostly because they contain aluminum — and there’s no such thing as an aluminum-free antiperspirant. The logic is that if you don’t need to use antiperspirants, it’s best to avoid them just in case they could increase breast cancer risk. 

If you sweat a lot but want to cut back on antiperspirants, you don’t have to quit them altogether. This is because a small amount of aluminum entering the body is less likely to be harmful. So, instead of using antiperspirants multiple times a day, switch to use once daily. Or only use them on special occasions, when you really don’t want to sweat through your shirt.

If you’re mostly worried about body odor and not sweat stains, you can opt for deodorant over an antiperspirant.

You might also want to check that your antiperspirant or deodorant doesn’t contain parabens. Look for products labeled as “paraben-free,” or check the label for the common parabens methylparaben, propylparaben, butylparaben, and ethylparaben. If your antiperspirant or deodorant does contain one or more of these ingredients, consider switching to a paraben-free product.