When perspiration on the human body absorbs heat, some of the perspiration turns into water vapor?

Yes, this statement is true. Majority of the fluids in our body is water. So, when we perspire, it comes out as a salt solution. When the water vaporizes and turns into water vapor, it leaves white residues in our garments after a while. The salt can't be vaporized as fast as the water so it is left as a solid.