A memory foam mattress topper is a mattress cover composed of polyurethane with added chemicals to increase viscosity and density. As a result, the memory foam mattress topper softens and flexes in response to weight, returning to its original shape when not in use. Memory foam cradles your body and provides extra support at higher pressure points. The newer generation memory foam topper has an open-cell structure that reacts to body heat and weight, molding to your body. The open cell structure also increases the breathability of the memory foam mattress topper. The foam topper relieves pressure point, prevents pressure sores, and also reduces motion transfer, making the memory foam topper ideal for sharing a bed. Materials such as aloe vera and green tea extract can be added to a foam mattress topper to provide aromatherapy while sleeping. Today’s newer generation memory foam topper has a faster recovery or spring-back time. A mattress cover of bamboo fiber over the memory foam mattress topper can deflect moisture from the body to increase bedding comfort. Foam and memory foam mattress toppers can also have ripples, waves, and coils on its surface which massage the body. A foam topper can have sections of differently sized cells called zones which provide different effects, or the foam mattress topper can have support zones of different densities for orthopedic support.