Body odour, also known as bromhidrosis, is the unpleasant smell that can occur when you sweat. Human sweat is mostly odourless, but when bacteria on the skin break down the sweat into acids, it produces an unpleasant smell.
Sweat glands
The human body contains 3-4 million sweat glands. There are two types of gland:
- eccrine glands – spread across your skin, these are responsible for regulating your body's temperature by cooling your skin with sweat when you get hot
- apocrine glands – concentrated in your armpits, genital area and breasts, these glands develop during puberty and release scented chemicals known as pheromones
Eccrine sweat is usually odourless but can start to smell if bacteria get a chance to break down the stale sweat. It can also take on an offensive odour if you consume certain things, such as garlic, spices, alcohol and certain medications, such as some antidepressants.
But it is the apocrine glands that are mostly responsible for body odour because the sweat that they produce contains a high level of protein, which bacteria find easy to break down. Body odour is worse if you have a high level of apocrine sweat production, or there is lots of bacteria on your skin.
Who is affected
Everyone who has passed the age of puberty (and therefore developed apocrine glands) can produce body odour.
Factors that can make body odour worse include:
- being overweight
- eating a diet rich in spicy foods
- having certain medical conditions, such as diabetes (see the Body odour warning sign box in Body odour - treatment)
Men tend to sweat more than women and are more likely to have body odour.
Managing body odour
You can manage a body odour problem by getting rid of any excess skin bacteria and keeping the affected skin as dry as possible. This can often be achieved through simple hygiene measures.
Surgery is available for more severe sweating that cannot be treated by self-care measures and over-the-counter products. See Body odour – treatment for more information.
