What a change in body odour can tell you about your health

Body odour is a common occurrence that can provide clues about an individual's health. Sweat itself typically does not have a strong smell; instead, bacteria and fungi on the skin break down sweat components, resulting in odour. Factors such as heat, physical activity, diet, and hygiene can influence body odour. However, new or persistent changes in body odour should not be dismissed as mere hygiene issues, as they may indicate underlying health conditions requiring medical evaluation.

Hemanath M. J., a consultant in internal and family medicine, emphasizes that the apocrine glands in armpits, groin, and scalp contribute more to odour than eccrine glands, which cover most of the body. Stress can stimulate these apocrine glands, intensifying odour. Hormonal changes during puberty, menstruation, menopause, or other conditions can also alter sweating and body odour. For instance, an overactive thyroid may cause excessive sweating and make odour more noticeable.

A change in body odour is often temporary when there is a clear trigger, such as eating certain foods, starting medications, or undergoing hormonal changes. The odour usually returns to normal once the trigger is removed. However, a persistent or unexplained change in body odour may be linked to a skin condition or an underlying medical problem.

Skin infections in moist areas like the armpits or groin can alter odour, potentially accompanied by redness, soreness, itching, peeling, or discharge. Conditions such as erythrasma and fungal infections can produce distinct smells, particularly in warm, moist areas.

Certain metabolic conditions have been associated with distinctive odours. Uncontrolled diabetes can result in fruity or sweet-smelling breath due to ketone build-up. A rare condition called trimethylaminuria can cause a fish-like odour because the body cannot properly break down certain compounds. Despite some distinctive smells being linked to complications of diabetes, liver disease, or kidney disease, doctors caution against treating these smells as diagnostic tests.

The overall clinical picture, including symptoms, examination, and biochemical investigations, guides diagnosis. When there is a sudden change in body odour without an obvious cause, consulting a doctor is advisable. A doctor may consider recent changes, examine the skin, and order tests such as blood glucose and HbA1c, kidney and liver function tests, and thyroid profile.

Skin scraping or culture may be useful if an infection is suspected. While body odour can provide insights into health, it should not be used for self-diagnosis, as most changes have everyday explanations. Sudden, unexplained increases in sweating, night sweats, or odour accompanied by other symptoms like weight loss, excessive thirst, frequent urination, fatigue, swelling, fever, or skin changes should prompt medical attention.