Adding a fresh new shirt to your work rotation feels great (particularly if it’s custom made to your own measurements). But that feeling fades quickly if the shirt develops unsightly yellow stains under the armpits after just a few wears.

What causes armpit stains
It’s not you—it’s your deodorant. While you might assume at first that sweat is to blame, the discoloration is a result of the aluminum found in most widely available deodorants.

How to prevent armpit stains
Unless you work from home, the answer to this problem is not to skip deodorant entirely. Instead, you just need to get more selective. Not every brand is made with aluminum, and those that skip the discoloring ingredient often advertise their aluminum-free status on the label. These won’t be stocked by every pharmacy, but you can easily find them at a Whole Foods or over Amazon. This small purchase can reap big dividends by extending the life of every dress shirt in your closer.

How to treat armpit stains
But what about those unfortunate shirts that have already been yellowed? Don’t discount them just yet. You may be able to reverse the damage by picking up another product available at virtually any pharmacy: OxiClean. You’ll want to apply the cleaning solution to the shirt’s stained area and allow it to soak in before washing. The more heavily stained the area is, the longer the cleaning solution should be allowed to soak in.