Urine is a waste product that is excreted by the kidneys, and it can vary in color, odor, and consistency depending on a person’s diet, hydration levels, and overall health.

While urine usually has a mild odor, a foul-smelling urine can be a sign of an underlying health issue that needs attention.

1. Dehydration

One of the most common causes of foul-smelling urine is dehydration. When the body lacks sufficient water, the urine becomes more concentrated, resulting in a stronger and unpleasant odor.

Dehydration can occur due to excessive sweating, not drinking enough fluids, or certain medical conditions such as diabetes or kidney disease.

2. Urinary tract infection (UTI)

A urinary tract infection occurs when bacteria enter the urethra and multiply in the urinary tract.

Along with symptoms like frequent urination, pain or a burning sensation during urination, and cloudy urine, foul-smelling urine is often present in individuals with a UTI. The smell is usually strong and unpleasant, indicating the presence of bacteria or pus in the urine.

3. Cystitis

Cystitis is the inflammation of the bladder, commonly caused by a bacterial infection. It can lead to foul-smelling urine along with symptoms like pelvic pain, a persistent urge to urinate, and blood in the urine.

Cystitis can affect people of all ages but is more common in women due to the shorter length of the urethra, which makes it easier for bacteria to reach the bladder.

4. Kidney stones

Kidney stones are hard deposits of minerals and salts that form in the kidneys. They can cause severe pain in the back, lower abdomen, or groin, and may also lead to foul-smelling urine.

The strong odor is often a result of concentrated urine and the presence of various minerals in the urine. Other symptoms of kidney stones include blood in the urine and frequent urination.

5. Liver disease

Liver diseases such as cirrhosis or hepatitis can also contribute to foul-smelling urine.

When the liver is not functioning properly, it may lead to a buildup of certain compounds in the body, including those responsible for the unpleasant odor in urine. Individuals with liver disease may also experience other symptoms such as jaundice, fatigue, and abdominal pain.

6. Diabetes

Diabetes, particularly if uncontrolled, can affect the smell of urine. High blood sugar levels can cause the body to produce ketones, which are byproducts of fat metabolism. These ketones can be excreted in the urine, resulting in a sweet or fruity odor.

Foul-smelling urine in individuals with diabetes should be taken seriously and reported to a healthcare professional.

7. Bladder stones

Similar to kidney stones, bladder stones are hard mineral deposits that form in the bladder. They can lead to urinary issues such as frequent urination, pain or difficulty during urination, and foul-smelling urine.

The smell is often caused by the concentrated urine and the presence of minerals in the bladder. Bladder stones may require medical intervention for proper treatment.

8. STDs

Sexually transmitted diseases (STDs) such as gonorrhea or chlamydia can cause foul-smelling urine. These infections can affect the urinary tract, leading to symptoms like pain or a burning sensation during urination and an unpleasant smell.

Prompt diagnosis and treatment of STDs are crucial to prevent further complications and transmission of the infection.

9. Certain medications

Some medications can alter the odor of urine, making it foul-smelling. Antibiotics, vitamin B6 supplements, and certain chemotherapy drugs are known to have this side effect.

If foul-smelling urine coincides with starting a new medication, it is important to consult a healthcare professional to determine if it is a side effect and whether an alternative medication may be appropriate.

10. Certain foods and beverages

Finally, the consumption of certain foods and beverages can also cause foul-smelling urine. Asparagus, for example, can produce a temporary sulfur-like odor in urine.

Similarly, consuming strong-smelling foods like garlic or coffee can alter the odor of urine. While these changes are typically harmless, persistent and extremely foul-smelling urine should not be solely attributed to dietary factors and should be investigated further.