By SUSAN CALLAHAN, Associate Editor and Featured Columnist
If you suffer from allergens as I do, you are constantly on the look out for new ways to reduce the night time and morning time congestion. One common suspect is the mattress. Each Saturday, I air out my mattress in the belief that it helps to reduce dust mites. Because I have used mattress covers of every type, I decided to look into the science behind dust mite allergy prevention. Do mattress covers help prevent allergies to dust mites? Do they help reduce asthma and congestion from sinusitis?
The Enemies Are Tiny Yet Powerful
To understand dust mites, you have to understand your role in creating it. You know that snakes shed their skin. Well, we humans are also ...snakes.
We shed about 500 million cells of skin every single day. Ever wonder where dust comes from even though you have the windows closed? It comes from you. The skin we shed is a major component of the dust we find in our homes. The skin you shed contains cholesterol and squalene and makes up most of the dust in your home, according to a 1978 study led by Dr. Charles Wechsler and his team from Bell Laboratories in New Jersey. We shed so much skin that we actually replace our entire outer skin layer every 2 to 4 weeks, Dr. Wechsler noted.
Dust mites are tiny insects which feed on the skin we shed. Wherever we are, they are. As they eat the skin cells we shed, these dust mites leave feces all over the place. One substance in dust mite feces is a compound called "DerP1". It is the DerP1 which causes most allergic reactions.
In fact, over 16% of Americans are allergic to dust mites, according to the Dr. James Sublett of the Allergen Committee of the American College of Allergy, Asthma and Immunology.
Should You Use a Mattress Cover to Fight Dust Mites?
This one sounds like a no-brainer. But actually there is considerable debate and dispute among the scientific community about the effectiveness of barriers to protect you from dust mites.
On the pro-cover side, there are numerous one-off studies that confirm that using the right type of mattress cover will help to reduce asthma events caused by dust mites.
For example, a 2004 study from the Institute for Risk Assessment Sciences, Utrecht, the Netherlands discovered that children who are not exposed in their early years to dust mites from mattresses are less likely to develop allergies later, even if their mothers are allergic to mites. All of the 810 children in this study had mothers who were allergic to dust mites. They confirmed that using a mattress cover that mites cannot penetrate will reduce allergen exposure.
Filamentous Fungi. A 2001 study from the University of Greifswald in Germany discovered that filamentous fungi as almost as common as dust mites on domestic mattresses. They also found that using cotton mattress covers will not adequately prevent these fungi from growing and multiplying. Only synthetic mattress covers work for this purpose.
On the "mattress covers are useless" side is a 2008 mega-study led by Dr. Peter of the Nordic Cochrane Centre in Denmark. This mega study-of -studies analyzed 54 other studies involving 3002 people. In 36 of the 54 studies scientists examined the effectiveness of mattress casings, 10 examined chemical methods and 8 used a combination of mattress covers and chemical methods. Their conclusion? Mattress covers do not produce significant reductions in asthma events or allergic reactions to dust mites. They further slammed the door shut in the issue, stating that "It is doubtful whether further studies, similar to the ones in our review, are worthwhile". Ouch.
And yet...yet...allergy doctors continue to recommend that people with asthma use impermeable mattress covers. Why? Because in clinical practice - aka the real world --- mattress covers help. It makes imminent sense. Let's do a simple test in Let's Make a Deal style. If you are allergic to the DerP1 substance in the feces of dust mites, would you rather sleep directly on a layer of dust mite feces -that's the mattress behind Door Number One --- or would you prefer to sleep on a mattress that has a sheet of plastic between you and the layer of feces? Of course most of us would choose Door Number Two.
But that would be the wrong choice. That choice would not protect us entirely. Why? Because, to quote cartoonist Walt Kelly's character Pogo, "we have met the enemy and he is us." We are the food that feeds the mites. We are the dust. Ashes to ashes, dust to dust, as the saying goes. Not to get too morbid but the truth, scientifically any way, is that the only way to completely stop mites is to stop living.
Should You Use Baking Soda to Remove Dust Mites?
You may be one of the many people who sprinkle baking soda on your mattress to eliminate dust mites.
But does it really work? Here is what scientists say.
In a group of scientists from Walter Reed Army Hospital led by Dr. R.W. Russ tested the effectiveness of two substances -benzyl benzoate and baking soda -in controlling dust mites. They recruited two groups of patients with proven allergies to dust mites. The patients were split into 2 groups of 6 persons each. The groups then tested the baking soda, benzy benzoate and other substances on carpets.
Samples were collected from the carpets after three, six, nine and twelve months and examined for the presence of DerP1 and DerF1, compounds from the feces of the dust mites. The scientists found that the baking powder nor the benzyl bezoate were effective in reducing the number of dust mite allergens.