Siebers RW, Crane J. (2011)
Does bedding affect the airway and allergy?
Int. J. Occup. Environ. Med. 2011 Apr;2(2):65-75.
Over the past 15 years, various epidemiological studies have shown that bedding with synthetic filling is associated with a higher risk of asthma, allergic rhinitis and eczema than bedding with feather filling. Feather bedding items also appear to offer a degree of protection against these diseases.
This paper comprises a review of various publications that have investigated the issue of bedding in relation to the airway and allergies. The ISAAC study (International Study of Asthma and Allergies in Childhood), which collated data regarding the global prevalence of asthma and allergies, confirms that indoor allergens appear to be a key contributory factor in asthma. The sleeping area is of primary importance in this respect. Humans spend approximately one third of their lives in bed and therefore come into close contact with pillows, mattresses and bedding. The studies examined here analysed whether or not there was a link between the choice of bedding (synthetic or feather) and specific symptoms such as typical asthmatic respiratory sounds (wheezing), blocked noses or eczema. Furthermore, the use of medications (inhaled steroids) and the frequency of hospital stays in both groups were also examined.
Our analysis of the various publications confirms the hypothesis that synthetic bedding is more often associated with asthma and allergies than feather bedding. Moreover, sleeping in down and feather bedding appears to offer protection against the above-mentioned respiratory diseases. The mechanics underlying these effects are very complex. Beds with synthetic filling appear to contain a greater number of allergens and fungal spores, and so-called VOCs (volatile organic compounds) in synthetic beds also appear to play a role. However, further investigation is needed to determine exactly what role these elements play.
This paper establishes that there are clear benefits to using feathers and down in bedding compared to synthetic filling. A number of the publications examined in this review also postulate that feather and down even offer a "protective effect", with the majority of authors suggesting that the positive effects of feather bedding items are due to their closely woven threads.