Sweating Up a Storm This Summer? Here’s How to Get Rid of Those Armpit Stains

Written by

Stephanie NguyenSenior Editor of Cleaning & Organizing at Apartment Therapy
Stephanie NguyenSenior Editor of Cleaning & Organizing at Apartment Therapy
I cover all the ways to make your home sparkle with decluttering tricks, cleaning tips, and organizing hacks. I have more than five years of experience working in media and hold degrees in English and Journalism from the University of Hawaiʻi at Mānoa. I Iive with my husband and dog in Hawaiʻi.
published Aug 8, 2022
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It’s been a scorching summer — with all of us looking for ways to cool down. It’s no surprise that with the heat comes the sweat and with that the inevitable stains on your clothes, specifically at the armpits. My sweet husband has been dealing with this for years, often ruining some of his favorite T-shirts. And I was at my wits’ end scrubbing away at these stains again and again, only for it to not really get clean.

It turns out, these stains are so tough because there’s more than just sweat behind it. “These stains are stubborn because it’s not just sweat, it’s a reaction of the fats and proteins in sweat with the aluminum and zirconium in antiperspirant that then reacts with the fibers on your clothes,” explains Jennifer Ahoni, a principal scientist at Tide. “The longer they remain on your fabric, and set into the fibers, the harder it becomes to remove these stains.”

So why do we get armpit stains — and why are they yellow?

“Yellow underarm stains develop in a variety of ways. First, body oils can bind with the aluminum and zirconium in antiperspirant leading to yellowing over time. Body oils alone can also stain clothes yellow. Normally, sweat on its own won’t stain clothes, but it’s the combination of sweat and body oils that will turn clothes yellow over time,” says Ahoni.

Along with yellowing, sweat creates lingering odors, and the type of sweat you produce attributes to that smell. “The extra sweating caused by heat or physical activity comes from the eccrine gland in your skin, which is 99 percent water and doesn’t smell that bad,” shares Ahoni.  “In contrast, stress sweat comes from the apocrine gland in your skin and contains 20 percent fats and proteins — and smells really bad.”

This is due to the fact that these fats and proteins break down into even smaller, stinkier molecules that produce body odor smells. “ And while we mostly think of visible stains when it comes to doing laundry, up to 70 percent of soils on garments are invisible and made up of body soils like sweat and skin oils,” she adds.

But don’t sweat it — there’s a way to tackle these tough stains. Here’s how to get rid of armpit stains.

What you’ll need:

  • Warm water
  • A high-quality liquid detergent
  • Vinegar
  • Laundry softener

How to remove armpit sweat stains

Start by rinsing garments in warm water to dilute the stain. Then, pre-treat it with a mixture of a high-quality liquid detergent — Ahoni recommends Tide Hygienic Clean Heavy Duty Laundry Detergent — and distilled white vinegar. “Yellow armpit stains respond well to low pH,” says Ahoni. “Vinegar is a great DIY option to help.” Pour it all over the stain, rub gently, and let it sit for 20 minutes. Make sure that you don’t use pure vinegar, especially on Rayon fabrics, which can be easily damaged by it, cautions Ahoni. 

If the stain still won’t budge, you’ll need a tougher laundry product. “We recommend 9 Elements Purifying Softener as a laundry soak,” shares Ahoni. Create a mixture of softener and water at a ratio of 1-to-10. Soak your clothes in this for 20 minutes, stirring every five minutes. Then, toss it in the washer with other items. You may have to repeat this process before drying to eliminate the stains.

How to prevent armpit sweat stains

There are a three things that you can do to prevent these types of stains from occurring, shares Ahoni.

  • Switch to a deodorant that doesn’t contain aluminum zirconium.
  • Treat stains as soon as possible — don’t let them sit. “The longer stains are on a fabric, the tougher they are to remove,” she says.
  • Use a high-quality detergent regularly to remove both visible and invisible soils, all the way down to the fiber level. Over time, this will “prevent the buildup of body soils that lead to odors and dinge.”

It’s important to note that while you can’t always see body soils on garments, it’s crucial that they are cleaned thoroughly to prevent odors from “reblooming.” Using a high-quality detergent can stop this from happening, shares Ahoni, getting down to the microscopic level to remove both visible and invisible dirt, giving you a clean you can trust.