Understanding sweat and body odour
Your body odour is completely natural and all of us have our own distinct scent.
What is sweat?
Sweat is mainly water, but it also contains some salts. Sweat is made in glands in the deeper layer of your skin. These glands are all over your body but there’s more of them in your armpits, palms, forehead, and on the soles of your feet.
Why do you sweat?
The main function of sweating is to regulate body temperature by helping to cool it down when it’s too high. When the water in your sweat evaporates, it cools down the surface of your skin.
You might also sweat when you eat hot or spicy food, have a fever, or experience emotional distress.
If you sweat excessively, there could be an underlying condition causing it. Some of these conditions could include:
- Obesity or high levels of body fat
- hormonal changes that happen during menopause (hot flushes)
- infections or other illnesses linked with fevers
- diabetes
- an overactive thyroid (hyperthyroidism).
Some medications may also cause you to sweat a lot. These can include some medications used to treat depression like selective serotonin reuptake inhibitors (SSRI’s) and tricyclic antidepressants.
Why does sweat smell?
Sweat doesn't actually have a smell on its own. Your sweat glands secrete protein, which forms an odour when it is broken down by bacteria living on your skin. When they do this, they also produce waste products and it’s these waste products that cause the unpleasant smell. The reason the smell is usually stronger in your armpits, groin and feet is because those areas are usually hidden away from light, warmer and damper.
What does it mean if your body odour changes?
You might notice a change in your body odour if you start a new medication such as antidepressants. Some research suggests that a woman’s body odour changes depending on where she is in the ovulatory cycle.
You might also notice a different odour if you change your diet. Foods containing sulphur (like broccoli and cauliflower), spices, or drinking coffee and alcohol can all affect the way you smell.
Changes in body odour could also mean you might be sick or have an underlying condition. Conditions like diabetes, kidney disease, liver disease can make body odour worse.
If you have diabetes and your blood sugar levels get too high, your breath may start to smell fruity. If this happens suddenly, and you’re also urinating a lot, it’s important to see a doctor straight away.
Another condition that causes a change in body odour is trimethylaminuria. Trimethylaminuria is a metabolic disorder where the body is unable to breakdown trimethylamine. Trimethylamine is found in eggs, fish, liver and legumes. As the trimethylamine builds up, it’s released through sweat, breath, urine and reproductive fluids, leading to a scent that has a fishy odour. It doesn’t seem to contribute to any other health problems, and symptoms can be reduced with some dietary changes and specific soaps.
How can you manage body odour?
To limit body odour, it’s a good idea to not eat too much strong smelling or spicy food and limit how much coffee and alcohol you’re drinking.
It’s also important to follow these hygiene practices:
- wash your armpits, groin and feet at least twice a day with soap and dry thoroughly
- shave your armpits regularly to prevent too much heat building up
- use antiperspirants and deodorants
- change and wash your clothes regularly
If you have a problem with excessive sweating, or you have concerns about your body odour, it’s best to see your doctor for advice.
More information
Sources
https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/hormonal-endocrine-system
https://www.healthline.com/health/sudden-change-in-body-odor#causes
https://www.nhs.uk/conditions/body-odour-bo/
https://www.nhs.uk/conditions/excessive-sweating-hyperhidrosis/
https://www.sciencedirect.com/science/article/abs/pii/S1090513816301945?via%3Dihub
https://rarediseases.info.nih.gov/diseases/6447/trimethylaminuria
https://www.nhs.uk/conditions/antidepressants/side-effects/
https://www.abc.net.au/news/health/2016-01-19/why-am-i-so-sweaty-ways-to-stop-excessive-sweating/7097808
All information contained in this article is intended for general information purposes only. The information provided should not be relied upon as medical advice and does not supersede or replace a consultation with a suitably qualified Health Care Professional.