if sweat is odourless, why do our armpits smell?

When we perspire, bacteria on the skin multiply and break down sweat into acids which cause unpleasant body odour.

Body odour depends on where the excess sweating occurs and which type of sweat glands are involved. It’s usually worse in the armpits and the pubic region, and this is because of the special type of sweat glands found in those locations. They’re called apocrine glands and the sweat they secrete is thought to have a smell which is a sexual attractant.

Our body odour is specific to us and can be used – especially by dogs – to identify people. Each person’s unique body odour can be influenced by diet, gender, health and medication.

People who sweat too much (hyperhidrosis) may be susceptible to body odour – often the salt level of their sweat is too high for the bacteria to break down.