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 — sweat glands are all over the body. A person may have body odour when the skin's bacteria break down sweat into acid. This means bacteria and acids create body odour, not sweat itself.
Proper hygiene can often manage body odour, including:
- ✅ Applying deodorant
- ✅ Keeping the body clean
- ✅ Wearing clean clothes
However, body odour from medical conditions can persist, even with good hygiene.
Non-Serious Reasons for Body Odour
Most cases of body odour are from relatively simple causes:
- 🦷 Poor oral hygiene
- 🧄 Eating certain foods (garlic, spices) that are expelled through the skin
- 🔄 Hormonal changes (common in teenagers)
- 😰 Mental or physical stress
However, when someone who didn't smell badly suddenly does, it's unlikely they changed their whole diet or stopped washing properly. This warrants investigation.
Serious Medical Causes of Body Odour
🦠 Bromhidrosis
Bromhidrosis is a medical condition characterised by extreme body odour. It occurs when bacteria on the skin break down sweat, producing an abnormal smell similar to onions or sulphur.
Two types affect people:
- Apocrine bromhidrosis — The most common type. Causes excessive odour in the genital areas and armpits. The smell resembles raw meat, sulphur or onions.
- Eccrine bromhidrosis — Less common. Results in smelly sweat on the head, torso, feet and hands.
💧 Hyperhidrosis
Hyperhidrosis causes the body to sweat excessively. Although it doesn't cause odour directly, excess sweat mixes with bacteria, leaving an embarrassing body odour.
Two types:
- Primary hyperhidrosis — Causes excessive sweat in specific areas (feet, hands, groin, head). Usually hereditary, affecting about 5% of the population.
- Secondary hyperhidrosis — Excessive sweating from a medical condition or certain medications. Causes sweating all over the body but is reversible when the underlying condition is treated.
Medications that may cause excessive sweating include: iron and zinc supplements, antidepressants (Protriptyline, Norpramin, Pamelor), and pilocarpine (for dry mouth treatment).
😰 Stress and Anxiety
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 causes. It's a lifelong condition where the body can't produce sufficient insulin or use it properly to regulate blood sugar.
People with uncontrolled diabetes may develop ketoacidosis, which causes:
- ⚠️ Strange breath smell (like old fruit)
- ⚠️ Distinctive body odour
Warning: Ensure you visit your healthcare provider immediately if you experience these symptoms.
🫀 Liver or Kidney Disease
Liver or kidney disease can cause a bad body smell. These vital organs process and eliminate toxins from the body. If they aren't functioning properly, your body's smell will be strong and different.
This change in smell, along with changes in urination and other symptoms, may indicate liver or kidney damage.
👉 Book Kidney Function Test | Book Liver Function Test
🦋 Overactive Thyroid
An overactive thyroid may result in bad body smell from excessive sweating due to the hyperfunction of the thyroid gland. Thyroid dysfunction has immediate and long-term health implications.
🔬 STDs and UTIs
You may have a urinary tract infection (UTI) if your urine smells like sulphur. UTIs may also cause:
- ⚠️ Fishy-smelling urine
- ⚠️ Burning sensation
- ⚠️ Increased need to urinate
Certain bacterial infections, such as bacterial vaginosis, and sexually transmitted diseases like gonorrhoea and chlamydia, may cause a change in vaginal odour.
🦶 Skin Infections
If your smell comes from your shoes, you may have athlete's foot — a common fungal infection characterised by red, scaly skin. It causes burning, smelly, stinging and itchy feet.
If untreated, athlete's foot can spread to other body parts and even cause bacterial infections like cellulitis.
⚖️ Hormonal Imbalances
Hormone fluctuations may result in excessive sweating and body odour. This commonly affects:
- 🤰 Pregnant women
- 👩 Menopausal or perimenopausal women
- 👦 Teenagers
Symptoms may include increased sweating, night sweats and hot flashes.
🧬 Metabolic Disorders
Gene mutations may also affect body odour, though this is rare. Trimethylaminuria (TMAU) is a disease that prevents the liver from breaking down the chemical compound trimethylamine, leaving a fishy smell or smell like eggs.
When your body doesn't break down trimethylamine, 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. The symptoms stop when you reduce or stop taking these supplements.
How to Prevent Smelly Armpits
- 🚿 Wash armpits daily and after sweating
- 🧄 Avoid certain foods like garlic, onions, and alcohol
- 🧴 Use deodorant or antiperspirant
- ✂️ Shave your armpits to reduce bacteria buildup
When Should I See a Doctor?
Everyone's armpits smell occasionally — this 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.
See a doctor if:
- ❌ Your armpits smell frequently despite good hygiene
- ❌ You experience a sudden, persistent bad smell
- ❌ The smell is accompanied by other symptoms
- ❌ It's affecting your social life and causing distress
Bromhidrosis and hyperhidrosis can cause social problems and distress, so ensure you consult with your GP.
Tests That May Help Identify the Cause
- 🔬 Diabetes Test
- 🔬 Kidney Function Test
- 🔬 Liver Function Test
- 🔬 Thyroid Function Test
- 🔬 Hormonal Analysis
- 🔬 STI Screening
🏥 Visit Walk In Clinic London
If your armpit smell is embarrassing and persistent, don't suffer in silence. Our experienced doctors can help identify the underlying cause and recommend appropriate treatment.
Call us on 020 71833649 to book an appointment.