Picking a Safe Deodorant: A Dermatologist's Checklist

Deodorant is one of those everyday products where the marketing is louder than the science. Here is what a dermatologist actually looks at when the underarms are sensitive, minus the fear-based claims.

Deodorant vs antiperspirant

They are not the same product. Deodorant tackles odour, usually by controlling the bacteria that break down sweat. Antiperspirant contains aluminium salts that temporarily reduce how much you sweat. If wetness bothers you, you want an antiperspirant; if only smell does, a plain deodorant may be gentler.

The aluminium question

You have probably seen "aluminium-free" sold as safer. The large reviews of the evidence do not support a link between antiperspirant aluminium and cancer or other serious disease. Going aluminium-free is a perfectly valid personal preference, but it is a choice, not a medical necessity for most people.

What actually irritates sensitive underarms

• Fragrance, the single most common cause of underarm reactions.
• High alcohol content, which can sting and dry the thin underarm skin.
• Baking soda, whose high pH triggers rashes in a lot of people.
• Strong essential oils, which are natural but still common allergens.
• Applying right after shaving, when the skin barrier is briefly broken.

A simple checklist

• Prefer fragrance-free or low-fragrance if your skin reacts.
• For irritation-prone skin, look for baking-soda-free formulas.
• Choose antiperspirant for wetness, deodorant for odour only.
• Apply to clean, dry, un-shaved skin, ideally at night.

Patch test a new deodorant on your inner forearm for two or three days before putting it under your arms. If a product repeatedly causes an itchy, sore rash, stop and speak to a doctor rather than pushing through it.