Does Aluminium in Deodorant Cause Breast Cancer?

Does aluminium cause breast cancer?

In 2012, studies about aluminium in antiperspirants and a possible connection with breast cancer made their way into the mainstream media, raising questions about an ingredient millions of women were using every day.

More than a decade later, there is still no clear, definitive answer.

The important thing to say upfront is that there is currently no established causal link between aluminium-containing antiperspirants and breast cancer. The available research hasn't demonstrated that using an aluminium antiperspirant causes breast cancer¹.

But that doesn't mean there are no questions worth asking.

Aluminium exposure, absorption through the skin and the effects of long-term exposure have been studied for decades. Aluminium has been detected in human breast tissue², in breast cyst fluid³ and in nipple fluid⁴, although finding aluminium in breast tissue does not, by itself, establish that it causes breast cancer.

So where does that leave us?

For us, it comes down to a slightly different question.

What does the research say about aluminium and breast cancer?

This is where it gets interesting.

In 2005, Professor Philippa Darbre at the University of Reading published a paper setting out why aluminium salts, applied daily to the underarm, warranted closer study. She pointed to the disproportionately high number of breast tumours occurring in the upper outer quadrant of the breast, the area nearest the underarm, and to aluminium's ability to interfere with oestrogen receptor function in breast cells grown in the lab⁵. Chemicals that behave this way are sometimes called metalloestrogens.

Two years later, a study measuring aluminium in breast tissue taken after mastectomy found significantly higher concentrations in the outer regions of the breast than the inner ones².

Later work found aluminium in breast cyst fluid at a median of 150 µg/L, against around 6 µg/L in blood serum³. In 2011, the same group analysed nipple fluid from 19 women with breast cancer and 16 without, and found mean aluminium concentrations of around 268 µg/L in the breast cancer group compared with around 131 µg/L in the group without, a statistically significant difference⁴.

However, these findings do not prove that aluminium caused the cancer.

That's an important distinction, and the researchers themselves make it. Darbre's own 2011 review, which gathers this evidence together, states plainly that the presence of aluminium in breast tissue does not demonstrate that it causes breast disease⁶.

Breast cancer is complex. There are many established risk factors, and finding a substance in breast tissue doesn't tell us whether it contributed to a tumour forming.

A 2023 systematic review of everyday aluminium exposure found no causal link, while noting that the authors would still choose to avoid aluminium antiperspirants on precautionary grounds⁷.

If you came here hoping we'd confirm that aluminium deodorant causes breast cancer, we can't do that, and we wouldn't want to.

So, should you avoid aluminium deodorant?

That's a personal decision.

Some people are perfectly comfortable using an aluminium antiperspirant. Others would rather avoid it as a precaution.

We're firmly in the second camp.

That isn't because we can point to clear, conclusive proof.

It's because we don't think aluminium is necessary to make an effective deodorant.

And when something is designed to be used every single day, often for decades, we prefer to ask a slightly broader question than "has this been proven harmful?"

We ask:

"Is there a good reason to use it at all?"

For us, the answer is no.

That's why Awake Organics deodorants are made without aluminium salts. We don't block your sweat glands. We don't try to stop your body doing something perfectly natural.

We simply help you smell good while your body gets on with being a body.

There's a wider picture behind all of this: how much aluminium is absorbed, what shaving changes, what the safety limits are measuring, and what else turns up on an antiperspirant label. We've covered that in Is natural deodorant healthier for you? Starting with aluminium.

A note on the evidence

Science is rarely as black and white as a headline makes it sound.

If future research gives us better answers about aluminium exposure and long-term health, we'll pay attention. That's part of being led by evidence.

For now, the most honest answer to "does aluminium in deodorant cause breast cancer?" is this:

No causal link has been clearly established. And since aluminium-free deodorant works perfectly well, we'd rather make that.