Is it normal to have a sour smell? Understanding body odor changes

September 25, 2025 •

5 min read

Did you know that sweat itself is odorless until it mixes with bacteria on your skin? Understanding this interaction is key to knowing if is it normal to have a sour smell, which can be caused by various factors from diet to hygiene and underlying health issues.

Quick Summary

While a sour smell can be a common and normal result of bacterial activity, it can also signal diet issues, stress, or more serious conditions like diabetes or infection. The cause determines whether it is a temporary, harmless occurrence or a sign that warrants medical attention.

Key Points

Bacteria are the cause: A sour smell is produced when bacteria on your skin break down sweat, primarily from your apocrine glands.
Diet plays a role: Foods like garlic, onion, and high-protein diets can influence your body's odor by releasing volatile compounds through sweat.
Stress is a factor: Stress can trigger excessive apocrine sweating, providing more material for odor-causing bacteria.
Hormones can shift odor: Life stages like puberty, pregnancy, and menopause cause hormonal changes that can affect body scent.
Underlying conditions may be to blame: Diabetes, kidney issues, and skin infections can cause a persistent sour smell and require medical attention.
Hygiene is key for prevention: Regular washing with antibacterial soap and wearing breathable fabrics can help manage body odor.

The Science Behind Your Scent

Sweat is a natural and necessary bodily function that keeps you cool. Your body has two main types of sweat glands: eccrine and apocrine. Eccrine glands are all over your body and produce clear, salty sweat that is typically odorless. Apocrine glands are concentrated in areas like the armpits and groin and produce a thicker, milkier sweat that contains proteins and lipids.

The sour or tangy smell associated with body odor, known as bromhidrosis, arises when the bacteria on your skin break down the proteins and lipids from the apocrine sweat. The waste products of this bacterial feast are what create the characteristic sour smell. This means that while some degree of body odor is normal, a strong or persistent sour smell can be a sign of changes in your diet, hormones, or an underlying health issue.

Common Causes of a Sour Smell

Several factors can influence the activity of your apocrine glands and the bacteria on your skin, leading to a sour body odor.

Lifestyle and Dietary Factors

Diet: Certain foods can influence your body odor. The way your body metabolizes foods like garlic, onions, curry, and cumin can produce sulfur-like compounds that are released through your sweat. High-protein, low-carb diets can cause the body to burn fat for energy, producing ketones that can result in a vinegar-like smell.
Poor Hygiene: Infrequent washing or not thoroughly drying skin folds can lead to an accumulation of bacteria, causing a more pronounced sour odor. The constant moisture in areas like under the breasts or in the armpits creates an ideal breeding ground for bacteria.
Stress: Emotional sweating, triggered by stress and anxiety, is primarily released by the apocrine glands. This stress-induced sweat is thicker and provides more fuel for odor-causing bacteria, leading to a stronger smell.
Medications and Supplements: Some drugs, including certain antidepressants and supplements, can alter your body's chemical balance and affect your natural odor.

Hormonal Changes

Hormonal fluctuations throughout your life can alter your sweat production and scent.

Puberty: As apocrine glands become active, teenagers often experience a change in body odor.
Menstruation and Pregnancy: Changes in hormone levels can affect how much and what type of sweat is produced.
Menopause: Hot flashes and night sweats are common during menopause, and fluctuating hormone levels can lead to changes in body odor.

Underlying Medical Conditions

While often harmless, a persistent or sudden change in body odor can sometimes signal a more serious health issue.

Diabetes: Uncontrolled diabetes can lead to diabetic ketoacidosis, a serious condition where the body breaks down fat for energy. This produces ketones, causing a distinct fruity or vinegar-like smell on the breath and skin.
Kidney or Liver Disease: When these organs are not functioning properly, waste products can build up in the body and be released through sweat, resulting in a distinct, often sour or ammonia-like smell.
Infections: Bacterial infections like trichomycosis, a bacterial infection of the underarm hair, can cause a very strong sour smell. Fungal infections in skin folds, a condition called intertrigo, can also produce a foul, sour odor.
Hyperhidrosis: This is a condition of excessive sweating that can lead to more frequent and noticeable body odor.
Trimethylaminuria (TMAU): A rare genetic disorder where the body cannot break down the chemical trimethylamine, leading to a pungent, fishy odor in sweat, urine, and breath.

Comparison of Common Causes for Sour Body Odor


Cause	Mechanism	Symptoms	Management	When to See a Doctor
Diet	Metabolizing certain foods (e.g., garlic, red meat) releases volatile compounds in sweat.	Temporary, odor occurs after eating specific foods.	Avoid or limit trigger foods; stay hydrated.	Odor persists even after dietary changes.
Stress	Cortisol and adrenaline trigger apocrine sweat glands, producing thicker sweat.	Occurs during periods of high stress or anxiety.	Relaxation techniques, stress management.	Persistent issue that interferes with daily life.
Hormonal Changes	Fluctuations (puberty, menopause) alter sweat production and composition.	Accompanied by other hormone-related symptoms.	Good hygiene, breathable fabrics.	Accompanied by other concerning symptoms.
Poor Hygiene	Bacteria multiply in moisture trapped in skin folds.	Strong, localized odor.	Regular washing with antibacterial soap, proper drying.	Odor persists despite good hygiene.
Medical Conditions	Underlying issues like diabetes, kidney disease, or infections.	Accompanied by other illness-related symptoms.	Treat the underlying condition.	Sudden, unexplained, or persistent odor, especially with other symptoms.

How to Manage and Prevent Sour Body Odor

Managing and preventing a sour smell often involves a combination of lifestyle and hygiene adjustments.

Enhance Hygiene Practices: Shower or bathe daily, and always after intense exercise. Use an antibacterial soap to reduce the odor-causing bacteria on your skin. Pay special attention to areas prone to sweating, like armpits, groin, and under breasts.
Use Deodorants or Antiperspirants: Deodorants mask odor, while antiperspirants contain compounds that temporarily block sweat glands. For excessive sweating, a doctor may recommend prescription-strength products.
Wear Breathable Fabrics: Opt for natural fabrics like cotton, wool, and linen that allow your skin to breathe and wick moisture away. Avoid tight-fitting or synthetic clothing that can trap sweat.
Adjust Your Diet: If you notice a connection between certain foods and your odor, try reducing your intake of high-sulfur foods like garlic and onion, and be mindful of red meat and dairy.
Stay Hydrated: Drinking plenty of water can help dilute the compounds in your sweat and urine, making odors less concentrated.
Manage Stress: Since stress contributes to apocrine sweating, practicing relaxation techniques like deep breathing, meditation, or exercise can help reduce its impact on body odor.
Address Skin Fold Infections: For conditions like intertrigo, keeping the area clean and dry is crucial. Special washes or topical treatments may be needed for severe cases. You can learn more about this condition by visiting MedlinePlus on Intertrigo.

When to Consult a Doctor

While most cases of sour smell can be addressed with home remedies, some situations warrant a medical consultation. You should see a doctor if:

The sour smell is a sudden, significant change from your usual odor.
The odor persists despite good hygiene and dietary adjustments.
The smell is accompanied by other symptoms like fever, pain, fatigue, or changes in your urine or skin.
You suspect an underlying medical condition, such as diabetes, kidney issues, or an infection.

Conclusion

While it's normal for body odor to fluctuate, a persistent or sudden change resulting in a sour smell can be worth investigating. The cause can range from simple dietary choices and stress to more significant medical conditions. By observing your body's patterns and making appropriate lifestyle changes, you can often manage the issue effectively. However, it is always wise to consult a healthcare provider for any persistent, unexplained, or concerning changes in body odor to rule out potential health issues.

Frequently Asked Questions

A sour smell from the armpits is quite common. It occurs because the apocrine glands, concentrated in that area, produce sweat rich in fats and proteins that bacteria on the skin feed on, creating odor. Regular hygiene and using antiperspirant can usually manage it.

Yes, certain foods and diet types can affect your body odor. Foods with high sulfur content, such as garlic and onions, can be excreted through your sweat. Additionally, high-protein or low-carb diets can produce a vinegar-like scent due to the body burning fat for energy.

Stress can cause you to produce a different type of sweat, primarily from the apocrine glands, which contains more proteins and lipids. When bacteria break down this sweat, it can result in a stronger, sour odor.

While often harmless, a persistent or sudden sour smell can be a sign of an underlying medical condition. Examples include uncontrolled diabetes, kidney or liver disease, and bacterial or fungal infections.

To get rid of a persistent sour smell, ensure good hygiene by showering daily with antibacterial soap, wear clean and breathable clothing, and consider dietary changes. If the problem persists, consult a doctor to rule out any underlying health issues.

Yes, bacterial or fungal infections, especially in warm, moist areas like skin folds, can cause a foul or sour smell. The condition is known as intertrigo and is often accompanied by a red, raw, and itchy rash.

You should see a doctor if the sour smell is a sudden and unexplained change, if it persists despite good hygiene, or if it is accompanied by other symptoms like fatigue, pain, or excessive thirst. A doctor can help determine the cause and recommend treatment.

Yes, hormonal shifts can change your body odor. This is common during puberty, menstruation, pregnancy, and menopause, as these periods affect the activity of sweat glands and the composition of sweat.