I guess you are a fellow sweat hog
Its most noticeable on black shorts and other black colored clothing. On very long rides in the summer I even notice salt deposits (as I call them) on my arms. If you don't clean up your helmet like I have to, the straps turn white where there's build up is heaviest, nothing some soap and water can't prevent, if you don't do it the straps get super nasty after a while.
I've started to use that new deodorant detergent Win (not an advert, I'm sure there are other brands) which helps keep the kit from reaking due to the excessive sweat.
Notes from a fellow sweat hog.