Why Do My Armpits Smell Like Onions?

Advertisements

It's totally normal for your armpits to smell like onions, but there are a few ways to stop the stink. Image Credit: SabdiZ/iStock/GettyImages

We've all done the "turn and whiff" — you know, when you try to slyly turn your head to see if your pits are stinking up a storm? But what happens when that smell is…onion-y?

Video of the Day

If you're wondering why your body odor smells like onions, just know that it's not all that weird. Some people just smell like onions.

Here's why that can happen, plus tips for how to get rid of onion-smelling sweat.

What Causes Body Odor to Smell Like Onions?

"Sweat feeds the bacteria present on the skin, and that bacteria produces an odor," Deirdre Hooper, MD, a board-certified dermatologist at Audubon Dermatology in New Orleans, Louisiana, tells LIVESTRONG.com.

And everyone has a different microbiome (the diverse colony of microorganisms like bacteria that live all over your body), which is influenced by things like diet, stress, environment and genes.

"The reason why someone's sweat smells stinkier is based on their own microbiome. It doesn't mean that you're dirty," Dr. Hooper says. Ditto if you've got a sour body odor.

A January 2015 study in ​Microbiome​ swabbed the underarms of 24 white people. They found that those who didn't use antiperspirants tended to have about 50 times more bacteria than those who swiped with these topical sweat-stoppers. Interestingly enough, armpit odors ranged from "sulfury-cat urine" to "acid-spicy," "foot" (moldy) and "fresh onion."

Bottom line: If your armpits smell like onions, you just happen to have that type of bacteria that gives you that odor.

Related Reading

5 Causes of Garlic Breath or Body Odor

How to Stop Armpits From Smelling Like Onions

Advertisements

If your pits have an onion scent, consider switching from deodorant to antiperspirant. Image Credit: katleho Seisa/E+/GettyImages

So, here's the deal: There isn't good science to support that diet changes (like eliminating garlic or onions) are going to get rid of onion-smelling sweat.

"You can try it, but my advice is keeping the sweat under arms to a minimum," Dr. Hooper says.

Advertisements

Because sweat feeds bacteria, stopping sweat will be the best way to control underarm odors, onion-y or not:

1. Clean Those Pits

Prevention starts in the shower. Look for a gentle soap (like Dove), an antibacterial wash or a cleanser with sodium hyochlorite like CLn BodyWash.

"A good 10 to 15 seconds of massaging a cleanser into underarms will do a nice job of temporarily ridding bacteria in this area," Dr. Hooper says.

2. Dry Them Well

Here's a trick worth trying, Dr. Hooper says: After you shower, use a blow dryer to fully dry your underarms. Use a warm — not hot — setting and stop before/if any redness occurs.

The dryness creates a less-friendly environment for bacteria to flourish, which can help prevent sweat from smelling like onions. If you notice any other folds of your skin smell — under the breasts, on your belly, in your groin — you can use the hairdryer to dry those areas, too, she says.

3. Use Antiperspirant

OTC and prescription-strength antiperspirants are available. These traditionally use aluminum to temporarily plug sweat ducts, though some natural antiperspirants use alternative ingredients to decrease sweating.

(There is no scientific evidence to say that an antiperspirant will up your risk of cancer or other major health risks, though talk to your doctor if you have severe kidney disease, per Penn Medicine.)

In the 2015 ​Microbiome​ study mentioned above, people who had a more intense onion armpit odor were those who didn't use antiperspirants.

4. Consider Botox

If antiperspirants are not enough and sweating is extremely bothersome for you, talk to your doctor about whether you're a good candidate for Botox injections.

"This is a safe and effective way to decrease sweating," Dr. Hooper says. It's also perfectly OK to stop sweat in this area — your body won't have problems cooling itself off because your armpits aren't sweating.

Insurance may cover Botox after you've tried other treatments, so ask about their requirements.

Related Reading

This Is Why Your Deodorant Isn't Working Anymore

Advertisements