How to choose an antiperspirant or deodorant: what to look for on the label

3 min read

In "Start odor care with your armpits and the soles of your feet," I wrote that underarm odor isn't sweat itself, but what skin bacteria make when they break down sweat and skin oils.

So what should you look at when choosing from the shelf of antiperspirants and deodorants? Start by separating whether what you want to control is "sweat" or "odor."

Antiperspirants and deodorants do different jobs

Antiperspirants are mainly for reducing sweat itself. Deodorants are mainly for curbing bacterial overgrowth and odor. In practice, many products contain ingredients for both.

• Wet underarm patches on your shirt bother you → something with sweat-reducing ingredients
• Odor bothers you more than the amount of sweat → something with ingredients that curb bacteria or odor

Look at the "active ingredients"

In Japan, where I live, most products claiming to reduce sweat or odor are classed as "quasi-drugs" and list their "active ingredients" on the package. (In the United States, antiperspirants are regulated as over-the-counter drugs and also list an active ingredient.) Looking there tells you what the product is designed to do.

Among sweat-reducing ingredients, aluminum chloride is considered strong-acting but also more likely to irritate the skin. The Japanese Dermatological Association's clinical guidelines recommend topical aluminum chloride as the first-line treatment for "primary focal hyperhidrosis," excessive underarm sweating [1].

If you sweat so much it gets in the way of daily life, rather than putting up with store-bought products, you have the option of seeing a dermatologist.

Is aluminum safe?

You may have heard that "the aluminum in antiperspirants causes breast cancer."

The European Commission's Scientific Committee on Consumer Safety (SCCS) assessed the safety of aluminum in cosmetics and concluded that it is safe in non-spray antiperspirants and deodorants up to 6.25% (as aluminum) and in sprays up to 10.60% [2].

Meanwhile, a 2023 systematic review found that studies on the link between antiperspirant/deodorant use and breast cancer were inconsistent, and no clear conclusion could be drawn. The authors also said that, as a precaution, it may be better to avoid antiperspirants containing aluminum [3].

For now, the accurate picture is that there's no basis for calling it "dangerous," but the assessments don't entirely agree either. If it worries you, you can choose an aluminum-free deodorant that curbs bacteria and odor.

Guidelines for choosing

Foot odor involves not just sweat but humidity inside your shoes. Foot care is covered in the original article.

If you choose by these guidelines