This definitely adds an extra layer of cushion to your mattress. I just purchased an 8" Wayfair memory foam mattress and wanted something on top of it to add some extra oomph. As far as keeping me cooler at night, I haven't noticed a big difference. Actually, at certain times, I find that it tends to absorb my body heat and make me hotter. This will be great in the winter months. In the spring/summer months, not so much. However, I do realize that memory foam tends to do this, so I'm not disappointed.