I hate to be rude but don't listen to those crackheads. It has nothing to do with cancer! And everybody sweats. Some people have a different chemical make-up then others. This can be hereditary. But it's the chemical make-up of your body that leaves the shirts yellowed. I have tried many different home remedies such as baking soda, and vinegar. None of it works.
Deodorant generally takes care of smell.
Antiperspirant makes it so you don't perspire (sweat) as much.
You can find some product with both.
Maybe you can try using scotch guard on those areas.
Or as soon as you take off your shirt spray on some Spray and Wash.
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