What causes sweaty skin to smell?

Dr. Michael Roizen, MD
Internal Medicine

Body odor or BO, as it is affectionately called, is not due to perspiration per se, but rather the bacteria that feast on its chemicals.


Sweat is actually completely odorless until it comes into contact with bacteria that normally live on the surface of our skin. The bacteria break down the proteins and fats in sweat into fatty acids and ammonia. The result? Fairly putrid BO. People with certain metabolic disorders are at higher risk of body odor, and they can produce odors that smell like fish. Talk to your doctor about what options (other than deodorant) might work for you.

Continue Learning about Functions of Skin

How do skin tags affect my skin health?
Diana MeeksDiana Meeks
Skin tags are small growths of skin that usually form on the neck, armpits, and groin areas. They're...
More Answers
What is the role of squalane in the skin?
Ben KaminskyBen Kaminsky
Squalane is a naturally occurring oil found in human skin. This fine emollient does a superb job...
More Answers
Is it normal to sweat from only one armpit?
Dr. Mehmet Oz, MDDr. Mehmet Oz, MD
Watch this video to learn more from Dr. Mehmet Oz about sweating.
More Answers
What are the essential components of stratum corneum?
Dr. Mehmet Oz, MDDr. Mehmet Oz, MD
The stratum corneum, also known as the skin barrier, is the outermost layer of skin which protects u...
More Answers

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.