We often think of body odour as an awkward inconvenience – something to hide with deodorant or a quick shower. But the smells our bodies produce can actually reveal a surprising amount about our underlying health.
Where does body odour come from?
Our scent begins with sweat – but not all sweat is created equal. Most body odour arises from bacteria interacting with secretions from apocrine glands, found mainly in the armpits and groin.
These glands produce a thicker, protein-rich fluid that has very little smell on its own. But when skin bacteria break it down, we get the familiar, pungent armpit odour.
In contrast, eccrine glands, which are distributed across almost the entire body, secrete a more dilute mixture of water and salt. This usually has little inherent smell, though it can still contribute to odour when bacteria proliferate on the skin.
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What can body odour say about your health?
Subtle shifts in scent can sometimes signal underlying medical issues. For example, poorly controlled diabetes can lead to a sweet, fruity smell on the breath or skin, often described as similar to pear drops or nail polish remover.
This can be a sign of diabetic ketoacidosis, a medical emergency in which a lack of insulin causes ketones to build up in the bloodstream.
Similarly, liver disease has long been associated with a distinctive musty or ‘faecal’ smell, while kidney failure can cause an ammonia-like odour as the body struggles to clear waste products.
Infections can also alter odour, as can hormonal changes such as pregnancy, menstrual cycles and menopause.
Intriguingly, scientists are now exploring whether human odour could help diagnose disease earlier and more accurately.
Recent research into conditions like Parkinson’s disease has shown that specific volatile organic compounds (VOCs) released through the skin may change long before more obvious neurological symptoms appear.
This field was partly inspired by observations from individuals with an unusually heightened sense of smell – including one woman who famously detected a distinct musky odour in her husband years before he was diagnosed with Parkinson’s.
Lifestyle, diet, and genetics
Of course, not all odours are a cause for concern. Foods such as garlic, onions and curry contain volatile compounds that are excreted through sweat. Alcohol, caffeine, and various medications can alter your scent too.
Even stress can influence how we smell via changes in sweat composition.
Your natural skin microbiome – the communities of bacteria that live on your skin – also plays a huge role, which is why some people naturally produce a stronger odour than others.
What can you do if body odour is worrying you?
Good hygiene is the most important thing. Regular washing with soap, particularly in areas dense with apocrine glands, reduces the bacteria responsible for breaking down sweat.
Antiperspirants reduce sweat production, while deodorants mask odour.
Wearing breathable fabrics such as cotton or moisture-wicking materials can limit bacterial growth, especially during exercise. Staying well hydrated and eating a balanced diet can also moderate scent.
If odour changes are persistent, unexplained, or accompanied by other symptoms- especially in the context of diabetes, liver, or kidney disease – it’s worth seeking medical advice.
This article is an answer to the question (asked by Scott Edwards, Spalding) 'Can my smell reveal anything about my health?'
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