How to remove sweat stains and yellow pit stains

How to remove sweat stains

1. 1

   Pretreat the stained area

   Rub liquid laundry detergent or a prewash stain remover into the underarms, collar or band, or work in bar soap. Leave it 5 to 10 minutes.

   Why: Detergent lifts the body oils that hold sweat residue and grime in the fabric.

2. 2

   Soak in an enzyme or oxygen bleach solution

   Soak the item in warm water with an enzyme presoak or oxygen bleach, from 30 minutes for light yellowing up to overnight for old stains.

   Why: Enzymes break down the protein part of sweat, and oxygen bleach oxidizes the yellow discoloration.

3. 3

   Fix a color change, if there is one

   If the sweat has changed the fabric's color, dab household ammonia on a fresh stain or white vinegar on an old one, after testing on a seam. Rinse well.

   Why: Fresh sweat tends to be acidic and old sweat alkaline, and the opposite pH can sometimes bring a dye back.

4. 4

   Wash in the hottest safe water

   Launder in the hottest water the care label allows, with a full dose of detergent.

   Why: Once the stain is pretreated, heat helps detergent remove the body oil that keeps yellowing coming back.

5. 5

   Air-dry and repeat if needed

   Air-dry and check in daylight. Old yellowing often takes several rounds of soaking and washing.

   Why: Dryer heat and ironing bake leftover residue into the fabric.

What actually makes sweat stains yellow

Sweat itself is mostly water with salts, lactic acid and urea. The underarm glands add an oily secretion, and skin adds body oils that build up in collars and hat bands. Sweat counts as a protein stain, so heat sets it, but the yellow comes from layers of residue that pile up over many wears and washes.

In the underarms, aluminum salts from antiperspirants join the mix. Iowa State Extension notes that these aluminum compounds can bond with fabric, so some underarm stains won't come out completely no matter what you use. That's why the method relies on enzymes to digest protein, oxygen bleach to oxidize color, and hot water to shift oil. Stiff white residue after washing is a separate problem: see deodorant stains.

Sweat stains on colored shirts

Colored fabric limits your options. Use oxygen (all-fabric) bleach rather than chlorine, and test hydrogen peroxide, ammonia and vinegar on an inside seam first, because each can change some dyes. The Kentucky extension guide also notes that sweat itself can change dye color, which is where the ammonia and vinegar step comes in. Iowa State Extension lists a 10 to 15 minute soak in undiluted white vinegar for underarm stains.

For whites, you can go further. See sweat stains on white clothes for peroxide soaks and how far to push them.

Sweat on every surface

The method changes with the surface: fabrics can soak, carpets and mattresses can't. Pick yours for the full steps.

By situation

Stains that survived washing and drying

They're set. Soak in oxygen bleach or an enzyme presoak for 30 minutes to overnight, wash in the hottest safe water, and repeat over several washes. Expect improvement rather than a guaranteed fix.

Yellowed white shirts

Oxygen bleach soaks work, and Iowa State Extension also lists equal parts 3% hydrogen peroxide and water. For white cotton T-shirts, its AnswerLine service suggests salt and fresh lemon juice, then drying in the sun.

Baseball caps and hats

Many caps shouldn't be machine washed or soaked. Fold the sweatband forward and clean it with mild detergent or an enzyme product in cool water, then air-dry the cap in its natural shape. See sweat stains on hats for structured brims and trims.

Yellow stains on white shoes

Yellowing on white sneakers isn't always sweat. Detergent residue and sunlight are other suspects, and no authoritative source gives a proven fix. Hand-clean with mild detergent and a soft brush, rinse well, and air-dry away from heat and direct sun. Shoe makers rule out chlorine bleach.

Silk and wool

Don't use enzyme presoaks, which digest protein fibers, or chlorine bleach. If you use ammonia, dilute it with an equal amount of water. Hand-wash or dry-clean as the label says.

What not to do

• Don't iron or machine-dry stained areas. Heat sets the protein and oil residue that causes yellowing.
• Don't mix ammonia or vinegar with chlorine bleach. Ammonia and bleach release chloramine gas, and vinegar and bleach release chlorine gas.
• Don't count on chlorine bleach for yellow pit stains. The guides recommend enzymes or oxygen bleach instead, and chlorine bleach damages silk, wool and the spandex in many shirts.

Other methods that work

Baking soda paste

Iowa State Extension lists a paste of baking soda and water, left on for 30 minutes to overnight, for underarm stains. As a mild alkali, it helps loosen fatty residue.

Caution: Rinse well before washing.

3% hydrogen peroxide

Mixed with an equal amount of water as a soak, it oxidizes yellowing on whites.

Caution: It can lighten dyes, so test on colors. Use only the 3% drugstore strength.

Salt and lemon juice in the sun

Iowa State's AnswerLine suggests this for white T-shirts: the mild acid plus sunlight acts as a gentle bleach.

Caution: Whites only. It can weaken or yellow some fibers.

Stain still there?

The underarms are stiff and white after washing

That's antiperspirant build-up. Pretreat with prewash remover for 5 to 10 minutes and wash with oxygen bleach. Kentucky and Texas A&M note that heavy aluminum or zinc salt build-up may be impossible to remove.

The stain is gone but the shirt still smells

Body-oil residue is still holding odor. Wash again in the hottest safe water with an enzyme product or oxygen bleach. See sweat smell in clothes.

Safety

• Never combine ammonia, vinegar or chlorine bleach. Rinse thoroughly between products.
• Use only 3% hydrogen peroxide, not hair-bleaching strength.

Never mix cleaning products; see chemicals you must never combine.

Questions

Other protein stains

• Blood stains
• Cat urine stains
• Dog urine stains
• Milk stains
• Poop (feces) stains
• Semen stains
• Urine stains
• Vomit stains