What causes body odour and how can it be prevented?

Almost everyone worries about underarm odour at some point or another. It can potentially lead to some embarrassing social situations and unpleasant conversations. Body odour, clinically known as bromhidrosis, is caused by the breakdown of sweat by bacteria. Wearing constricting, heavy layers of clothing exacerbates sweat and can cause more odour. For example, you may have noticed your musk more since the onset of winter.    

[caption id=“attachment_7900751” align=“alignleft” width=“380”]  Representational image. Image by DrawnByShaun from Pixabay.[/caption]

Breaking down body odour

Sweat is produced largely by two types of glands: eccrine and apocrine. The former covers most of the body and acts as a cooling system - during physical exertion, sweat evaporates from the skin and helps maintain healthy body temperature. The apocrine glands, on the other hand, are present where there is a large number of hair follicles, like the genitals and underarms. Unlike eccrine glands, which open directly on the surface of the skin, apocrine glands open into the hair follicle which leads to the surface of the skin. They only start working after the onset of puberty, which is why body odour is first noticed then.   Sweat is odourless until bacteria interact with it and produce foul-smelling chemicals called thioalcohol. The sweat produced by apocrine glands is richer in protein, which can be easily broken down by bacteria. It is also produced is a warm, moist, and dark environment - ideal breeding conditions for bacteria.  

No reason to sweat it - usually

While body odour is not usually a cause for concern, it can be a consequence of underlying health issues. An overactive thyroid gland can cause excessive sweating, whereas liver disease, kidney disease and diabetes change the composition of sweat and alter the smell. If you notice that you are sweating significantly more than usual, or sweating is suddenly disrupting your life, it is a good idea to see your physician. Hyperhidrosis, a condition in which one sweats excessively from the armpits, hands and feet, is also diagnosed by a professional and there are several treatments available to manage it.

Armpit innovations

A study conducted in 2015 by researchers at the University of York claimed that body odour was caused by a bacteria called Staphylococcus Hominis. It is a part of the microbiome of the underarm and the researchers found that even a small amount of it released high amounts of thioalcohol on interaction with sweat. That was the first time the biological pathway of body odour was understood. Unilever, the cosmetics company, partly funded the study.   Unlike current antiperspirants and deodorants, targeted oral treatment could be more effective in attacking the underlying cause of body odour. It will still be a long time before any practical application is developed; further studies need to be carried out and the microbiome needs to be understood better. It is not known yet if there are a ‘good’ bacteria involved in sweating, but it is an educated approach to fully understand the mechanism before introducing further interventions. An underarm microbiome transplant, pioneered by a scientist at Ghent University in Belgium who calls himself Dr Armpit, may have an exciting future as well. The idea is to replace the microbiome of someone suffering from chronic body odour with a microbiome that breeds ‘good’ bacteria. This, however, is a new area of study and the results have been mixed so far.   Botox has also been used as an effective treatment against body odour.

Easy ways to beat body odour

There are luckily many little things you can do to mitigate body odour:

1. Maintain good hygiene: Bathing regularly with antibacterial soap goes a long way in combating unpleasant odours.
2. Shaving the armpits: Studies have shown that shaving significantly reduces underarm odour since hair traps more moisture and makes the environment more conducive for bacterial growth.
3. Dietary changes: Consuming large amounts of spicy food, or caffeinated beverages may make you sweat more and cause more body odour.
4. Looser clothes: Breathable, natural fabrics such as cotton do a better job of ventilating the skin and help sweat evaporate faster.
5. Deodorants and antiperspirants: Deodorants mask the smell of sweat using fragrances and turn the skin slightly acidic which discourages bacterial growth. Antiperspirants temporarily block sweat glands. Both provide some protection for at least 12 hours.  

For more on this topic, please read our article on   Hyperhidrosis: Symptoms, Causes and Treatment_._ Health articles in Firstpost are written by myUpchar.com, India’s first and biggest resource for verified medical information. At myUpchar, researchers and journalists work with doctors to bring you information on all things health.