Body Odour and Bromhidrosis: Causes and What Helps

Sweat on its own has almost no smell. Body odour develops when bacteria living on the skin break down sweat, mainly from the apocrine glands in the underarms and groin, and when the odour is strong and persistent despite normal hygiene, doctors call it bromhidrosis. Most people improve with washing twice a day, drying well, using an antiperspirant, wearing breathable clothes and managing heavy sweating, while a dermatologist can offer further treatment and check for less common medical causes.

Body odour is something many people in India worry about quietly, especially in humid summers, crowded commutes and long workdays. It is common, it is not a sign of being unclean, and it is treatable.

Why does body odour happen?

Your skin has two main types of sweat glands:

• Eccrine glands, spread across the whole body, produce watery sweat that cools you down
• Apocrine glands, found mainly in the underarms, groin and around the nipples, become active at puberty and produce a thicker sweat containing fats and proteins

DermNet explains that odour comes from bacteria on the skin, such as Corynebacterium and Staphylococcus species, breaking down sweat, sebum and skin debris. This is why underarm odour usually starts at puberty.

A 2024 review of underarm bromhidrosis also notes that genetics play a role. Variations in a gene called ABCC11 influence how much odour the apocrine glands produce, and these variations differ between populations.

What is bromhidrosis?

Bromhidrosis means a persistent, unpleasant body odour that is stronger than usual and does not improve with normal hygiene. DermNet describes two types:

• Apocrine bromhidrosis, the most common, affecting the underarms and groin
• Eccrine bromhidrosis, more widespread and often linked to heavy sweating, certain foods, medicines or metabolic conditions

What makes body odour worse?

Common contributing factors include:

• Heat and humidity, which increase sweating
• Excessive sweating (hyperhidrosis). Our hyperhidrosis guide explains this in detail
• Synthetic, tight clothing that traps sweat
• Underarm hair, which holds sweat and bacteria
• Higher body weight, with more skin folds
• Diabetes
• Strong smelling foods such as garlic, onions, certain spices, and alcohol
• Stress and anxiety, which trigger apocrine sweating
• Skin infections, such as erythrasma in the folds or pitted keratolysis on the feet
• Certain medicines

Rarely, an unusual body odour has a metabolic cause. Trimethylaminuria, sometimes called fish odour syndrome, causes a fishy smell in sweat, breath and urine. Liver and kidney disease can also change body odour. These need medical assessment.

What daily habits help?

NHS advice and dermatology sources suggest:

1. Wash the underarms, groin and feet at least twice a day in hot weather with soap or an antibacterial wash, and dry thoroughly
2. Use an antiperspirant, not just a deodorant. Applying it at night on dry skin often works better, because sweat glands are less active then
3. Wear loose, breathable fabrics such as cotton and linen, and avoid tight synthetic clothes
4. Change clothes and socks daily, and more often if you sweat heavily
5. Wash clothes properly and dry them completely in the sun
6. Keep underarm hair short by trimming or shaving if it helps you
7. Air your shoes and rotate pairs. Use moisture wicking socks
8. Notice your diet. If certain foods make odour worse, reduce them
9. Manage stress where possible

Deodorant or antiperspirant: which should I use?

Product	What it does	Best for
Deodorant	Masks odour with fragrance, some reduce bacteria	Mild odour, little sweating
Antiperspirant	Reduces sweat, so less for bacteria to act on	Odour with sweating
Antibacterial wash	Reduces skin bacteria	Underarm and foot odour
Strong prescription antiperspirant	Stronger sweat reduction	Heavy sweating, under medical advice

If a product causes itching, redness or a rash, stop it. You may be reacting to a fragrance or other ingredient. Our guide to contact dermatitis from hair dye and other products explains how such allergies happen.

What about foot odour?

Feet have many sweat glands, and closed shoes in hot weather create the perfect environment for bacteria. Helpful steps:

• Wash and dry feet carefully, especially between the toes
• Wear cotton or moisture wicking socks and change them daily
• Alternate shoes so each pair dries fully
• Treat athlete’s foot or other fungal infections. Read our guide to ringworm and tinea in India
• See a doctor if you notice small pits on the soles, which can be pitted keratolysis, a bacterial infection linked to sweaty feet

What can a dermatologist offer?

If daily measures are not enough, your dermatologist may:

• Look for and treat skin infections such as erythrasma or pitted keratolysis
• Prescribe topical antibacterial treatments in selected cases
• Treat excessive sweating with stronger antiperspirants, iontophoresis for hands and feet, botulinum toxin injections for the underarms, or oral medicines
• Suggest laser hair reduction for the underarms. See our laser hair reduction guide
• Consider procedures such as microwave or laser based treatments, or in severe cases surgery to reduce underarm sweat glands, after discussing risks and benefits
• Arrange tests if a medical cause is suspected

Results vary, and no treatment works for everyone. Surgery is usually reserved for severe cases where other options have failed.

Does body odour change with age, hormones or life stage?

Yes, and knowing this can be reassuring.

• Puberty: apocrine glands switch on, so underarm odour often appears for the first time in the early teens. Teenagers benefit from learning simple habits early, such as daily bathing, clean clothes and an antiperspirant. Our teen skincare routine covers the basics
• Hormonal changes: some women notice changes in sweating or odour around periods, pregnancy or menopause
• Exercise and work: physically demanding jobs, sports and long hours in uniforms or protective clothing increase sweating and odour
• Stress: sweat produced during anxiety comes partly from apocrine glands and may smell stronger than sweat from heat

In children before puberty, a strong body odour is unusual. DermNet advises that investigation is warranted in children with body odour, and in anyone with a generalised odour affecting breath and urine as well as sweat.

What are common body odour myths?

• More perfume fixes it. Fragrance on top of sweat often makes the smell stronger and can irritate the skin
• Body odour means poor hygiene. Many people with bromhidrosis wash often. Genetics, sweating and skin bacteria matter more
• Antiperspirants are dangerous. For most people they are a safe, effective first step. Stop any product that irritates your skin
• Home remedies like lemon or baking soda under the arms cure it. These can irritate thin underarm skin and cause rashes or dark marks

When to see a dermatologist

See a dermatologist or doctor if:

• Odour continues despite good hygiene and antiperspirants for a few weeks
• Body odour has changed suddenly or smells unusual, such as fishy or sweet
• You also have heavy sweating, especially at rest or at night
• You notice rashes, brown patches in the folds, or pits on the soles
• You have other symptoms such as weight loss, excessive thirst, fever or yellowing of the eyes
• Odour is affecting your confidence, relationships or work

Talking about body odour can feel awkward, but it is a routine concern for dermatologists. If you would prefer to discuss it privately, Dr. Maria offers online consultations where you can explain your symptoms and get a clear plan.