I bought this sheet as I sweat at night (due to medication) and I am terrified this will ruin my new mattress. I chose this sheet because it claims to be waterproof and breathable (to keep my temperature down). Unfortunately, after one nights' use, I removed the sheet to find that my mattress was wet with smelly sweat. The sheet claims to withstand "accidents" that might occur if your young child is sleeping with you and I definitely sweat a smaller volume than that, so I'm really gutted this sheet didn't work ......back to the drawing board I guess and I'm 45 pounds down as well.......