What Are Dust Mites?

You've probably heard the saying that an average mattress doubles in weight over its lifetime due to the increased presence of dust mites, dust mite feces and human skin cells. But is there any merit in this statement? First, let's look at what exactly dust mites are and how they affect human lives.

Dust Mites – The Stats

Dermatophagoides pteronyssinus – a.k.a. the "American Dust Mite" – is a tiny member of the arachnid family that's a common houseguest in modern society. These dust mites thrive in our homes, living off of the skin cells we shed on a daily basis. Typically, these mites are about .5 millimeters in length, and slightly less in width, so they can be seen by the naked eye. Both males and females of the species are creamy white in color, with a striated cuticle running up their backs, so they're best spotted against a dark surface or background.

Male dust mites may live for 20-30 days on average, while impregnated females can last up to 70 days, laying anywhere from 60-100 eggs during the second half of their lives. These mites find it easy to set up shop in your home, as their small sizes allow them to bury deep in your furniture – evading vacuum cleaners, the sun and other obstacles – and their rapid reproductive cycle allows them to quickly colonize an area.

Dust Mite Allergens

Most people who are allergic to dust mites are actually allergic to their feces. Because the dust mite has no stomach, the digestion of skin cells and other bits of organic matter must occur primarily outside the body. To accomplish this, the dust mites secrete enzymes and the fungus Aspergillus repens on to dust particles, allowing the enzymes and fungus to pre-digest the food for them. In addition, the dust mite will need to consume the same particle several times in order to digest all the nutrients available to it.

The inevitable consequence of all this eating is dust mite feces, a common cause of allergies and asthma in humans. In fact, over its lifetime, the average dust mite will produce over 2,000 feces and even more partially-digested dust particles. Clearly, these can quickly add up if your house becomes infested with dust mites.

Preventing Dust Mite Infestation

Although it's nearly impossible to rid your home of dust mites entirely, there are a few steps you can take to minimize their impact on your life. Frequently wash any bedding or blankets in water that's at least 140o Fahrenheit, or find a way to freeze them regularly – which will also kill off dust mites. Dust mites also require at least 50% humidity to survive, so turn off your humidifier occasionally to help prevent outbreaks.

So, as for that rumor about your mattress doubling in weight? You can rest assured that it's not true. Although dust mites will take up residence in your mattress, they aren't so prolific that you'll soon see them taking over. Fortunately, with a few simple steps, you can reduce the impact dust mites have in your household, dramatically improving your quality of life.