7 Medical Conditions That Cause Body Odor

Body odor: It’s embarrassing to talk about and usually blamed on poor hygiene. Not bathing regularly, wearing dirty clothes and not using deodorant are typical culprits.

But stinky armpits and smelly sweat aren’t always due to skipping a shower. Certain medical conditions that are out of your control can also cause body odor.

Today we’ll take a closer look at what diseases can cause bad body odor and what you can do to fight back.


Did you know that sweat, on its own, has no fragrance? There are sweat glands all over your body. Body odor happens when bacteria that live on your skin break down sweat into acids. Bacteria + acids = B.O.

Most body odor can be managed with proper hygiene. Keeping your body clean, applying deodorant, and wearing fresh clothing can help manage your body odor. However, body odor caused by certain medical conditions can be persistent problems — even with stellar hygiene practices.

Read: The 6 Best Deodorants For Body Odor


What diseases can cause bad body odor? Beyond hygiene, there are certain cases where diseases or medical conditions can alter a person’s body odor. Here are some of the top medical conditions that cause body odor.

1. Bromhidrosis

Bromhidrosis is a medical condition that causes extreme body odor. It occurs when your skin’s bacteria breaks down sweat and produces an abnormal smell that mimics sulfur or onions. There are two types of bromhidrosis: apocrine and eccrine.

  • Apocrine bromhidrosis is the most common type, causing excessive odor in your armpits and genital areas. This odor happens when sweat from apocrine glands mixes with skin bacteria, creating a smell that can resemble onions, sulfur or raw meat.
  • Eccrine bromhidrosis is a lesser-known form of bromhidrosis, causing smelly sweat on the hands, feet, head and torso. This odor happens when sweat from eccrine glands softens the skin’s keratin, breaking down bacteria that produce excessive odor.

2. Hyperhidrosis

Hyperhidrosis causes your body to sweat more than normal. While hyperhidrosis doesn’t cause odor itself, excessive sweating mixes with your body’s bacteria creating embarrassing body odor. There are two main types of hyperhidrosis: primary and secondary.

  • Primary hyperhidrosis causes excessive sweat in one body area, like the underarms, hands, feet, head and groin. It’s usually hereditary and affects approximately 5% of the population.
  • Secondary hyperhidrosis is excessive sweating caused by a medical condition or certain medications. Secondary hyperhidrosis causes all-over sweating and can be reversed if the underlying medical cause is resolved or eliminated. We’ll talk about some of these medical conditions in this article.

Some medications whose side effects can include excessive sweating are:

  • Antidepressants (Pamelor, Norpramin, Protriptyline)
  • Pilocarpine (used to treat dry mouth)
  • Zinc supplements
  • Iron supplements

3. Diabetes

Diabetes patients often experience additional medical complications. Diabetes-related urinary tract infections (UTIs) and high levels of blood glucose can increase body odor. Diabetic ketoacidosis is a life-threatening condition in which your body lacks insulin, depriving cells of the sugar they need for energy. One of the symptoms is a distinct, fruity breath smell.

Contact your physician for medical advice immediately if you suspect you have diabetic ketoacidosis.

4. Thyroid Conditions

Thyroid glands regulate many bodily functions, including our sweat response. When you have hyperthyroidism (overactive thyroid) or Grave’s disease, your body can produce an excessive amount of sweat, even if you aren’t exerting yourself.

5. Kidney Failure and Liver Dysfunction

The kidneys and liver help remove toxins from our bodies. When they cannot function properly, toxins can build up in the blood and digestive tract, creating odor. Kidney disease can cause urea to make your sweat take on an ammonia smell.

If you suspect that you have a thyroid, kidney or liver condition, talk to a healthcare professional promptly.

6. Metabolic Disorders

While this is incredibly rare, gene mutations can also affect body odor.

Trimethylaminuria, or TMAU, is a disease that prevents your liver from breaking down the chemical compound trimethylamine. Trimethylamine can be fishy-smelling or reek of eggs or urine. When your body cannot break down this compound, it builds up in your body and is released in your sweat, urine and breath.

Secondary trimethylaminuria can occur if you take large oral doses of L-carnitine, lecithin or choline. Lecithin and choline are contained in some food supplements. L-carnitine is sometimes used to enhance athletes' strength, and choline treats Alzheimer’s and Huntington’s disease. Symptoms disappear when doses are reduced or eliminated.

7. Hormones

Hormone fluctuations can cause excessive sweating and, by extension, body odor. Teens, pregnant women, and perimenopausal or menopausal women can experience hot flashes and night sweats, increasing excessive sweating and odor.


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