I’m a proponent of NOT using most commercial / store-bought deodorants and anti-antiperspirants which contain aluminium salts (and other nasty, confusingly named chemicals). Aluminium salts have been linked, the stress is on ‘linked’, not proven, to Alzheimer’s disease. Although there is inconclusive evidence to directly link aluminium salts to health ailments, perhaps it’s best to avoid them if we can. Other more natural ways of getting rid of bacteria could be in the form of ethanol (as found in 40% or higher alcohols that do not have sugar), wiping down your armpits with anti-bacterial baby wipes, or keeping your pits clean and dry. AVOID wearing synthetic fibres like polyester and op for natural fibres like cotton! Your pits will thank you for it!