A traditional mattress cover protects and lengthens the lifespan of your mattress by keeping dirt and skin oils that can come through the sheets away from your mattress. The mattress cover is typically an inexpensive item that protects your investment in a mattress, which can be quite expensive.

Traditional mattress covers are composed of cotton, cotton blends or vinyl. People choose vinyl when they want to protect the mattress from moisture. For example, you might choose vinyl for a toddler’s bed. Vinyl is not particularly comfortable to sleep on because of the noise it makes when you move or change positions. It’s also hotter to sleep on than other materials.

An allergy mattress cover provides the same protection for your mattress and also protects you from allergens that can collect in your mattress over time and from anything that is there from the beginning, when the mattress is new. It would be more accurate to call it an “anti-allergy” mattress cover.

These anti-allergy mattress covers are composed of cotton, polyester or a cotton/polyester blend. They are never made from vinyl.

The fibers of the anti-allergy covers are woven very tightly to create a barrier. The loose weave of the traditional cover would not serve as a barrier to protect against common household allergens.

The anti-allergy covers are available in different pore sizes. The term “pore” refers to the amount of space between the fibers in the weave of the fabric. The space is measured in microns. The smaller the pore size, the more allergens the cover can keep out of the air and away from you.

Allergens that are commonly found in mattresses, especially those that have been used for a while, include dust, dust mites, dust mite excretions, molds and animal dander. These items are too large to pass through the pores of the barrier fabric. If you have severe allergies, shop for an allergy mattress cover with the smallest pore size available. A pore size of 8 microns or less will provide the most protection from the common allergens.

The only disadvantage to the smallest pore size is that the cover will usually be made of all polyester. Polyester fibers are very strong and can withstand the tight weave necessary to create the strongest barrier with the smallest pore size. But all polyester mattress covers tend to have a slick feeling that may be uncomfortable.

Cotton/polyester blends are an alternative. The pore size may not be the smallest available but the material feels more like cotton. Cotton/polyester blends are long lasting and generally comfortable to sleep on.

Another alternative is all cotton. Cotton has a soft and cool feeling that many people prefer. The pore size will be larger, because cotton fibers are not as strong as polyester and cannot be woven as tightly. Cotton may not last as long as polyester. So, there are advantages and disadvantages to each material.

There is a process that some manufacturers use to provide an all-cotton, anti-allergy mattress cover with many of the advantages of polyester. The process involves using heat, steam and/or pressure to “shrink” the pore size. Manufacturers who use this process will say that their covers are “sanforized”.

Sanforized cotton covers will retain their pore size through multiple washings. The process of washing and drying degrades cotton fibers causing some fibers to break and generally leaving you with a larger pore size. The sanforizing process also helps to prevent shrinking. So, your cover should continue to fit your mattress as times goes by.

Anti-allergy mattress covers are available in fitted and zip-on styles. Similar to your fitted sheets, the fitted style includes elastic bands that hold the cover in place. The zip-on style covers the entire mattress and is held in place by a zipper. The zip-on style provides more protection but is impractical in some situations.

When you are ready to make up your bed, it is recommended that the only things on top of the anti-allergy mattress cover are your sheets and bedding. Any pads, down or memory foam toppers should go under the anti-allergy cover. Allergens can also collect inside those “add-ons”. If they are on top of the mattress cover, you are not protected from those allergens.

Your sheets and bedding should be washed at least once a week in warm water and dried in your dryer on an appropriate setting. You can use a low heat setting on the dryer to help ensure that your bedding does not shrink. Although you may be bothered a bit by static electricity, you may want to avoid the use of fabric softener dryer sheets. The fragrance and chemicals left on the sheets can also be allergens.

All in all, most people with allergies feel that a good mattress cover is a worthwhile investment. Getting a good night’s sleep is important to your overall health. It’s easier to get a good night’s sleep when your allergies are put to rest.