One of the true draw-backs to memory foam mattress toppers is that they can absorb odors over time. And they’re not machine washable like cotton/poly toppers. The machine rips them apart and they’re just too big and bulky to fit anyway. You can keep your memory foam topper clean in 2 ways: 1.Get a mattress protector. These waterproof sheets are comfortable, affordable, and definitely the easiest option. They’re soft, just like regular sheets, but they stop any liquid or allergens from penetrating the foam. Plus, you can just wash them like regular sheets, so there’s no extra effort.   2.Grab the baking soda and your vacuum; this method is a bit more advanced, but can be used on your actual mattress too! Baking soda is perfect to use because it’s a natural deodorizer, eliminating any foul body odors in the foam. And it’ll absorb any moisture left over from sweat. Simply, sprinkle a light dusting of baking soda onto your topper and let it sit for a moment. Then vacuum it up, along with any dead skin cells that might be clinging to the surface of the foam. *If you want to go the extra mile, mix your favorite essential oil into the baking soda to leave a relaxing scent (lavender is perfect for this).