What the Smell of Your Pimples Can Tell You About Your Skin Health

Our bodies are capable of creating a lot of odd odors: from bad breath to gross gas, stinky sweat and even strange-smelling sneezes. And now you can add foul-smelling pimple pus to the list. Yep, pimples — when popped — can produce their own ‌bouquet‌ of scents.

If you've ever encountered a pungent pustule, you probably wondered what caused the stench and whether it was normal.

We spoke to Stacy Chimento, MD, a board-certified, Miami-based dermatologist at Riverchase Dermatology, to learn about what various types of pimple pus smells could say about your skin's health.

Acne is an inflammatory skin disorder that happens when oil glands become clogged with excess oil and dead skin cells, trapping bacteria in the pores, Dr. Chimento says. This process produces an inflammatory response, which results in the development of pimples that contain pus.

When you squeeze a zit and release the pus (mixed with bacteria, blood and debris), it can, at times, emit a foul or strange smell. This odor is simply the byproduct of the bacteria feeding on skin oil, Dr. Chimento says.

And while an occasional stinky spot isn't uncommon or cause for alarm, some scents — like the three listed below — can signal more serious skin issues if they occur frequently.

A foul-smelling secretion that with a yellowish, cottage-cheese appearance is probably related to an epidermoid cyst, a noncancerous bump beneath the skin.

"The skin is made up of a thin layer of cells that the body sheds," Dr. Chimento says. "An epidermoid cyst forms when these cells move deeper in the skin and multiply rather than slough off." Epidermoid cysts may also develop because of an injury or irritation, she adds.

These cysts typically have a cottage-cheese consistency — a thick, yellow substance made up of the protein keratin — which is secreted by epidermal cells, according to the Mayo Clinic. Sometimes, this liquid drains from the cyst, and you'll catch a whiff of potent odor.

Sulfurous smelling pus can be a sign of acne conglobata, a rare form of nodulocystic acne that commonly occurs when painful, large cysts connect deep beneath the skin, Dr. Chimento says. It can also occur with other cyst-forming conditions. Acne conglobata is a serious skin condition, which can also cause disfiguring, visible scars, she adds.

The first sign of acne conglobata is multiple inflamed nodules, which are filled with pus that may have a foul odor like rotten eggs, Dr. Chimento says.

If your blemish emanates an aroma of alliums (read: your pimple smells like garlic or onions), you can blame bacteria.

Zits are filled with pus, which is essentially dead white blood cells that provide a feast for infesting bacteria, Dr. Chimento says. These bacteria are mostly anaerobic (meaning they don't require oxygen to survive), and they generate their own sulfur compounds as they grow, she explains.

That's why when you pop a zit infested with this type of anaerobic bacteria, you may notice a smell of garlic or onions, whose signature pungent scent (and flavor) comes from the presence of sulfur-containing compounds.