Yellow discoloration on a white shirt can be the result of perspiration stains, bleach stains or the remnants of an old stain. No matter what the source of the stain, yellow discoloration on your white shirt ruins the appearance of the shirt. In addition to commercial products, natural remedies can help you return your white shirt to its original bright white condition.
Fill a bucket with enough undiluted white vinegar to cover the yellow stains on your white shirt. Allow your shirt to soak in the vinegar for an hour to loosen and remove the yellow stains.
Lay a towel outside in direct sunlight and place your vinegar-soaked, yellow-stained white shirt in the sun with the stains face up. Allow the white shirt to dry in the sun as the vinegar and sunlight work together to bleach out the yellow stains.
Flush the site of the yellow stains with cool water. Sprinkle baking soda over any remaining yellow stains and scrub with an old toothbrush.
Launder your shirt according to directions, using a heavy duty laundry detergent. Hang dry, outdoors if possible, until completely dry.