Basement Bathroom Drywall Behind Toilet
You can slow down condensation on cold water pipes by insulating them. 

What?  Insulate cold pipes???

Sure, why not.  The insulation doesn't care. The insulation will act as a vapor barrier to keep humid air away from the pipe, and will greatly slow the warm-up of the pipe.   Remember, in condensing conditions, what is warming the pipe is the enthalpy of vaporization as water vapor condenses.  The water vapor gives up 2257 joules/gram or 970 BTU/lb. when it transitions from vapor to liquid, and this is what warms the pipe until it equalizes to ambient.  The insulation greatly slows this process, reducing condensation greatly.