Q. Does an unmade bed kill dust mites?

A. Keeping relative humidity low in the home does help fight irritating dust mites, studies have found, but a British study, widely reported as having concluded that leaving the bed unmade could do the trick, suggested only that it might do so. Actual scientific comparisons of made and unmade beds were not done.

Dust mites, like Dermatophagoides pteronyssinus and Dermatophagoides farinae, are microscopic, eight-legged creatures that feed on skin cells. Their feces can set off asthma symptoms and cause allergic reactions in some people.

The British study, published in 2006 in the journal Experimental and Applied Acarology, suggested a computer model for predicting the effect on dust mites of different ranges of temperature and relative humidity. The researchers said they planned follow-up studies under real conditions, but have not reported on any.

A humorous 2001 article in The Canadian Medical Association Journal suggested that making the bed constituted a public health hazard, not just from dust mite proliferation but also from back pain from mattress lifting and marital disputes over whose turn it is to do it. No studies supported such conclusions.