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When do smelly armpits indicate a serious health problem?
13 Sep 2023

When do smelly armpits indicate a serious health problem?

Most people feel embarrassed talking about their armpits having a bad smell and often blame it on poor hygiene. Smelly armpits usually occur from wearing dirty clothes, not using deodorants, and not bathing regularly, but this isn’t always true.

Some medical conditions that you can’t control may cause body odour. Possible remedies for excessive sweating include injections, over-the-counter treatments and prescription medications.

You may want to visit Walk In Clinic London if your armpits have a bad smell that isn’t a result of poor hygiene and other common, temporary causes.

Where does body odour come from?

Sweat alone has no smell, and sweat glands are all over the body. A person may have body odour when the skin’s bacteria break down the sweat into acid, meaning bacteria and acids give body odour.

Proper hygiene can often manage body odour, including applying deodorant, keeping the body clean, and wearing clean clothes. However, body odour from medical conditions can persist, even with good hygiene.

What are the non-serious reasons why someone might smell a little?

  • Poor oral hygiene
  • Eating certain foods that, when expelled through the skin, may leave a strong smell. For example, garlic and spices
  • Hormonal changes (which leaves many teenagers with a smell), mental or physical stress

Most cases of body odour are from a relatively simple cause. However, when someone who didn’t smell badly suddenly does, it is unlikely they changed their whole diet or stopped washing up properly.

What are the serious reasons someone might start to smell?

  • Bromhidrosis

Bromhidrosis is a medical condition characterised by extreme body odour. This condition occurs when bacteria on the skin break down sweat, producing an abnormal smell similar to onions or sulphur. Two main types of bromhidrosis affect people.

Apocrine bromhidrosis – It is the most common type of bromhidrosis. It causes excessive odour in the genital areas and armpits. This odour occurs when skin bacteria mix with sweat from the apocrine glands, leaving a smell similar to raw meat, sulphur or onions.

Eccrine bromhidrosis is the less common type, resulting in smelly sweats on the head, torso, feet and hands. This odour occurs when the eccrine glands soften keratin in the skin, breaking down bacteria to produce excessive odour.

  • Hyperhidrosis

This condition causes the body to sweat excessively. Although it doesn’t cause odour, excess sweat mixes with the bacteria on the body, leaving an embarrassing body odour. Two types of hyperhidrosis affect people.

Primary hyperhidrosis causes excessive sweat in a body part, like the feet, hands, groin and head. This condition is usually hereditary and affects about 5% of the population.

Secondary hyperhidrosis is excessive sweating resulting from a medical condition or certain medications. This condition causes sweating all over the body and is reversible when the underlying condition is treated.

Some medications that may cause excessive sweating include iron and zinc supplements, antidepressants (Protriptyline, Norpramin, Pamelor), and pilocarpine (for dry mouth treatment)

  • Stress

Anxiety and stress can cause excessive sweating. Sometimes, anxiety can cause a sudden change in the armpit’s smell.

  • Diabetes

Diabetes is one of the most common serious reasons. It is a life-long and serious condition that causes an inability of the body to produce sufficient insulin or use insulin properly to regulate blood sugar levels.

People with diabetes have elevated glucose levels and, if uncontrolled, may result in ketoacidosis. Ketoacidosis causes a strange breath smell like an old fruit and also leaves a distinctive body odour. Ensure you visit your healthcare provider immediately if you experience this symptom.

  • Liver or kidney disease

Liver or kidney disease can cause a bad body smell. These vital body organs process and eliminate toxins from the body. If they aren’t functioning properly, the body’s smell will be strong and different. This change in smell, including changes in urination and other symptoms, may indicate liver or kidney damage. Visiting your doctor is important if you experience these symptoms.

  • Overactive thyroid

An overactive thyroid may result in a bad body smell from excessive sweating due to the hyperfunction of the thyroid gland. Thyroid dysfunction has immediate and long-term health implications, such as excessive sweating.

  • STDs and UTIs

You may have a urinary tract infection (UTI) if your urine smells like sulphur but you didn’t eat asparagus. UTI may also cause your urine to smell fishy and have a burning sensation or an increased need to urinate.

Certain bacterial infections, such as vaginitis, commonly called bacterial vaginosis, and sexually transmitted diseases (STDs), like gonorrhoea and chlamydia, may cause a change in vaginal odour and a fishy smell.

If you think you have a bacterial infection, STD or UTI causing your smell, visit the nearest walk in clinic for medical care from an experienced doctor.

  • Skin infections

If your smell comes from your shoes, you may have an athlete’s foot. Athlete’s foot is a common fungal infection characterised by red, scaly skin. It causes burning, smelly, stinging and itchy feet. If untreated, an athlete’s foot can spread to other body parts and other people, even causing bacterial infections like cellulitis. Ensure you visit your healthcare professional if you have an unexpected foot odour that you think results from an athlete’s foot. Your provider can offer guidance and medication to treat this fungal infection.

  • Hormonal imbalances

Hormone fluctuations may result in excessive sweating, preventing body odour. Pregnant women, menopausal or perimenopausal women and teens may experience increased sweating and odour, night sweats and hot flashes.

  • Metabolic disorder

Gene mutations may also affect body odour, but this rarely occurs. Trimethylaminuria (TMAU), a disease that prevents the liver from breaking down the chemical compound trimethylamine, can leave a fishy smell or a smell like eggs. When your body doesn’t break down trimethylaminuria, it accumulates and is released in your breath, sweat and urine.

You may experience secondary trimethylaminuria if you take large oral doses of L-carnitine, choline or lecithin. Some food supplements also contain choline and lecithin. Choline helps treat Huntington’s and Alzheimer’s disease, while L-carnitine enhances athletes’ strength. The symptoms stop when you reduce or stop taking the doses of these medications.

How to prevent smelly armpits

  • The best way to prevent your armpits from smelling is to wash them daily and after sweating.
  • Avoid certain foods like garlic, onions, and alcohol, which usually cause smelly armpits.
  • Use deodorant or antiperspirant, and shave your armpits

When should I see a doctor?

Everyone’s armpits smell occasionally, so it is normal and not usually a cause for concern. However, if your armpits smell more frequently, it can be uncomfortable and affect your everyday life.

Bromhidosis and hyperhidrosis can cause social problems and distress, so ensure you consult with your GP.

If your armpits smell frequently or you experience a sudden, persistent bad smell from your armpits, you may have a health condition that needs treatment to stop the smell. Visit Walk In Clinic London if your armpit smell is embarrassing. You can also call us on 020 7096 8853 to book an appointment with our experienced doctor.


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