Is potassium alum safe to use?

Potassium alum is generally considered safe for topical use in cosmetics, particularly in deodorants. Concerns about aluminum absorption are often related to aluminum chlorohydrate, which is a different compound.

How does potassium alum work in deodorants?

Potassium alum works by forming a thin, temporary barrier on the skin's surface, which helps to reduce the flow of sweat. It also has antimicrobial properties that inhibit the growth of bacteria responsible for body odor.

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Potassium Alum

Potassium Alum is a naturally occurring mineral salt that acts as an astringent and antimicrobial agent. In cosmetics, it is primarily used in deodorants to reduce perspiration and inhibit odor-causing bacteria. It forms a temporary barrier on the skin's surface, helping to keep skin dry and fresh.

NoneAstringentVeganEvidence: Medium

BenefitModerate 1.5 / 4

Oil control i1.5 / 4

Whether it can reduce excess sebum, shine, or greasiness — absorbents, sebum-regulating ingredients, and some acne actives.

RiskLow 1 / 4

Irritation i1 / 4

Risk of short-term irritation — stinging, burning, dryness, redness, or discomfort. Common for strong actives, acids, retinoids, fragrances, and harsh surfactants.

Rated by SpottyLabs' ingredient methodology, independent of brands.

What it helps with

reduces perspiration
inhibits odor-causing bacteria

Things to watch

can be irritating to sensitive skin

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Frequently asked questions

Is potassium alum safe to use?: Potassium alum is generally considered safe for topical use in cosmetics, particularly in deodorants. Concerns about aluminum absorption are often related to aluminum chlorohydrate, which is a different compound.
How does potassium alum work in deodorants?: Potassium alum works by forming a thin, temporary barrier on the skin's surface, which helps to reduce the flow of sweat. It also has antimicrobial properties that inhibit the growth of bacteria responsible for body odor.