They do relieve pressure on the back. If you like your current pillow top mattress, you could go with one that is a memory foam mattress at it's core with a pillow top cover over it. Very comfortable. See the link below for the one I own. Very comfortable.
yes
Unfortunately there is not a memory foam mattress topper that can be washed in the washing machine or dried in the dryer. Therefore, they are spot clean only.
It depends on the type of topper you are trying to buy for your mattress. There are memory foam toppers, pillow top toppers and even latex toppers for dust mites.
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The benefits of using a memory foam mattress topper are, body weight is equally distributed, heat sensitive memory foam, provides extra pressure and relief for a more comfortable sleep.
Typically, a memory foam mattress would cost between $1000.00 - $4000.00 depending on where you are buying it from, you can buy them at As Seen On Tv. Also, you can buy a topper instead, it is not the whole mattress but it costs a significant amount of less money.
The average price for a twin sized memory foam mattress topper is about sixty-five dollars. Although the can be purchased for as low as thirteen dollars or for over one hundred dollars.
A 3 inch memory foam mattress topper can be purchased from stores like Sears, Walmart, Target, and Bed, Bath, and Beyond. They can also be found on eBay.
The following are some foam beds available in Walmart; Spa Sensation 3" Airflow Visco Elastic Topper, Spa Sensation 4" Memory Foam Mattress-Topper, and Aerus Natural 6" Eco-friendly Memory Foam Mattress.
This depends on where one is purchasing a 4 inch Memory Foam Mattress Topper. For example, a site such as Amazon has it on sale for $172, while another site, Overstock, has it on sale for $220.
There are many different styles and types of beds available on the market. One great addition to your bed would be a "memory foam mattress topper." A topper such as this would offer greater support that would lead to a better night's sleep.