Sweat stains are one of the most frustrating laundry problems, because they often appear slowly and catch you off guard. The yellow marks under your arms come from sweat, body oils and the aluminum in some antiperspirants reacting together over time. Luckily, a few small daily habits make a big difference. Most of the fixes are simple and take only a minute or two.
Prevention starts with how you apply your deodorant. Then the way you handle sweaty clothes after you take them off matters just as much. Follow the steps below and your shirts will stay brighter for longer.
5 steps
Step by step
- 1
Start with clean, dry underarms
Wash your underarms with soap regularly and make sure they are fully dry before you apply anything. Shaving or trimming also helps, because hair collects more sweat.
Buildup on the skin gives sweat and product more to cling to, so this first step does a lot of the work.
- 2
Apply a thin layer
With a stick, use 2-3 long strokes per underarm for a thin layer. With a spray, shake the can, hold it several inches from the armpits and spray for 2-3 seconds.
Do not overapply. Too much product gives its ingredients more chance to mix with sweat and stain your shirt.
- 3
Let it dry completely
Give the product time to dry before you put on clothes. Applying it first in your routine makes this easy to do.
Wait until the deodorant is completely dry before dressing to limit transfer to your shirt.
- 4
Try applying it at night
Consider applying antiperspirant at night, when your skin is dry, to help reduce sweat. Choose the right antiperspirant for your skin and let it dry completely before you get dressed.
- 5
Pick a product that stains less
Aluminum-free products are less likely to stain than aluminum-based ones, though they can still stain. If the problem persists, try a different brand of deodorant or antiperspirant.
Why sweat and antiperspirant leave yellow stains
Yellow marks appear when proteins in sweat mix with aluminum from antiperspirants, body oils and detergent residue. Aluminum zirconium binds to sweat components and fabric, building up and discoloring into yellow underarm stains.
The staining does not develop immediately, so the marks often show up after several wears. Sweat, deodorant and hard water are the culprits behind armpit stains. Armpit stains depend on your deodorant, sweat, hygiene and laundry habits, so you can influence all of them.
Protecting white shirts
White shirts show every mark, so they need the most attention. Wash whites and light clothes as soon as you finish wearing them, to stop sweat bacteria mixing with deodorant ingredients and forming yellow stains.
Wear an undershirt, because it absorbs more sweat and protects the more expensive outer shirt. When you wash whites, use hot water on a heavy duty cycle for the best cleaning.
Washing sweaty clothes the right way
Let sweaty clothes and towels air dry before tossing them in the hamper. Do smaller loads every few days rather than letting sweaty clothes sit in the hamper.
Turn sweaty garments inside out before washing, because sweat and grime accumulate on the inside. Do not overload the washer, since clothing needs to circulate easily.
For a fresh stain, rinse right away with cold water, then apply liquid detergent directly to the stain before washing. An enzymatic laundry detergent helps remove deodorant and antiperspirant stains.
Hats, collars and other hard-to-reach spots
Hats and collars take in sweat in the same way underarms do, so the same habits apply. Let damp hats dry fully before you put them away, and let them air dry rather than going in a machine dryer.
Turn sweaty garments inside out before washing, since the inside of a collar is where sweat and grime collect. Air drying rather than machine drying helps keep stains from setting in further.
What makes sweat stains worse
Too much product is one of the most common mistakes. Do not overapply, because more product gives ingredients more chance to mix with sweat and stain.
Do not dress right after applying, since the product rubs off into crusty stains and residue. Avoid fabric softener too, because it traps residue in fibers and makes it harder to remove.
Sweat stains can weaken most fibers, so do not leave them to build up. Keep the shirt out of a hot dryer while any stain remains.
Questions
Why do my white shirts turn yellow under the arms?
Yellow underarm marks form when sweat reacts with aluminum salts in antiperspirant and with body oils and detergent residue. White shirts show these marks most clearly, so washing them promptly and using a thin layer of product both help. Oxygen bleach will not cause the yellowing and damage over time that chlorine bleach can.
Does aluminum-free deodorant prevent stains?
Aluminum-free products are less likely to stain than aluminum-based ones, but they can still stain. If you keep getting marks, try a different brand of deodorant or antiperspirant. Applying a thin layer and letting it dry fully matter just as much as the product you choose.
Can I put a stained shirt in the dryer?
No, not until the stain is completely gone, because dryer heat can make it impossible to remove. Air dry the shirt instead, since a hot dryer can set the stain further. Check the shirt once it is dry before you decide what to do next.
Should I use fabric softener on sweaty clothes?
It is better to skip it. Fabric softener traps residue in fibers, which makes stains harder to remove later. An enzymatic laundry detergent is a better choice for deodorant and antiperspirant marks.
Can I mix ammonia, vinegar and bleach to get out a stain?
No. Do not put ammonia and then chlorine bleach on the same stain, and do not combine the ammonia and vinegar steps. Use one product at a time and rinse in between so each one works on its own.
Can I treat sweat stains on silk or wool?
Be careful, because ammonia damages silk and wool. If you must use it on those fibers, dilute it with an equal amount of water and use it sparingly. Read the care label and test any stain solution on a hidden spot first.
How do I keep hats from getting sweat stains?
Let a sweaty hat dry fully before you store it, and air dry it rather than using a dryer. Wear breathable clothing when you sweat a lot, since it helps keep moisture from building up. Test any stain solution on a hidden spot first.
How long should I wait before getting dressed after applying antiperspirant?
Wait until the product is completely dry before you dress. Applying it first in your routine gives it time to dry. Getting dressed too soon can rub the product off into crusty stains and residue.
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Sources
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