Body Odor: what it usually means
Also searched as: bromhidrosis, strong body smell, excessive body odor · Updated 19 Aug 2026 · Educational — not medical advice
The short answer: Body odor is most often caused by bacteria breaking down sweat on the skin, particularly in the armpits and groin, and is influenced by diet, hygiene, hormonal changes, and certain medical conditions. Strong sweat gland activity during puberty commonly increases odor. A sudden change in body odor, especially a sweet, fruity, or ammonia-like smell, can occasionally signal an underlying metabolic or kidney condition and is worth mentioning to a doctor.
See a doctor promptly if…
A sudden, unexplained change in body odor, especially a sweet or fruity smell, should be checked for uncontrolled diabetes.
An ammonia-like or fishy body odor along with fatigue or swelling may indicate a kidney or metabolic issue needing evaluation.
Body odor that persists despite good hygiene and over-the-counter products can be evaluated for hyperhidrosis or another cause.
Body odor accompanied by unexplained weight change or excessive thirst should be checked promptly.
Common causes
- Bacterial breakdown of sweat — Bacteria naturally present on the skin break down proteins and fats in sweat from apocrine glands, producing the characteristic odor.
- Poor hygiene or infrequent washing — Sweat and bacteria that are not regularly washed away accumulate and intensify odor over time.
- Diet — Strong-smelling foods such as garlic, onions, and certain spices can be excreted through sweat and affect body odor.
- Hormonal changes — Puberty, menopause, and other hormonal shifts increase activity of sweat glands, particularly apocrine glands in the armpits and groin.
- Certain medical conditions — Diabetes, kidney or liver conditions, and some metabolic disorders can produce distinctive changes in body odor.
- Stress and anxiety — Emotional stress activates apocrine sweat glands specifically, producing a stronger odor than sweat from heat or exercise.
What helps
- Wash daily with soap and water, paying attention to areas prone to sweating.
- Use an antiperspirant or deodorant and change into clean, breathable clothing regularly.
- Consider dietary factors like garlic, onions, or alcohol that may be contributing to odor.
- Shave or trim underarm hair, which can reduce the surface area where bacteria accumulate.
Which doctor to consult
A dermatologist can address persistent body odor related to sweat glands; a family doctor should be seen if odor changes suddenly or is accompanied by other symptoms suggesting a metabolic cause.
Lab tests doctors often check
If this symptom persists, these are the values a doctor commonly looks at — and if you already have a report, the analyzer explains where you stand.
Questions people ask
Why does body odor get stronger with stress?
Stress activates apocrine sweat glands, found mainly in the armpits and groin, which produce a thicker, protein-rich sweat that bacteria break down more readily than the watery sweat produced during exercise or heat. This is why nervous sweating often smells stronger.
Can diet really change how you smell?
Yes, foods like garlic, onions, curry spices, and alcohol contain compounds that can be partially excreted through sweat glands and breath, temporarily intensifying body odor. Reducing intake of these foods or drinking more water can help lessen their effect for some people.
What does it mean if body odor suddenly changes?
A sudden change, particularly a sweet or fruity smell, can sometimes indicate poorly controlled blood sugar, while an ammonia-like odor may point to a kidney-related issue. If odor changes noticeably without an obvious reason like diet or hygiene, it is worth mentioning to a doctor.
Related symptoms
This guide is educational and doesn't replace a clinical assessment. If a symptom is severe, rapidly worsening, or worrying you, see a doctor — being checked and reassured is never a wasted visit.