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The Myth

Contrary to popular belief, so-called hypoallergenic dogs do not have lower household allergen levels than other dogs.

That’s the conclusion of a study by Henry Ford Hospital researchers who sought to evaluate whether hypoallergenic dogs have a lower dog allergen in the home than other dogs. Hypoallergenic dogs are believed to produce less dander and saliva and shed less fur.

Says Christine Cole Johnson, Ph.D., MPH, chair of Henry Ford’s Department of Public Health Sciences and senior author of the study:

We found no scientific basis to the claim hypoallergenic dogs have less allergen.

Interestingly, being immune to dog allergen works in a similar way to being immune to chicken pox.

Based on previous allergy studies conducted here at Henry Ford, exposure to a dog early in life provides protection against dog allergy development. But the idea that you can buy a certain breed of dog and think it will cause less allergy problems for a person already dog-allergic is not borne out by our study.

Methods

Henry Ford researchers analyzed dust samples collected from 173 homes one month after a newborn was brought home. The dust samples were collected from the carpet or floor in the baby’s bedroom and analyzed for the dog allergen Can f 1. Only homes with one dog were involved in the study. Sixty dog breeds were involved in the study, 11 of which are considered hypoallergenic dogs.

The Claims of the Myth

Based on public web site claims of hypoallergenic breeds, dogs were classified as hypoallergenic using one of four “schemes” based on their breed for comparing allergen levels.

  • Scheme A compared purebred hypoallergenic dogs to purebred non-hypoallergenic dogs
  • Scheme B compared purebred and mixed breed dogs with at least one hypoallergenic parent to purebred non-hypoallergenic dogs
  • Scheme C compared purebred and mixed breed dogs with at least one hypoallergenic parent to purebred and mixed breed dogs with no known hypoallergenic component
  • Scheme D compared only purebred dogs identified as hypoallergenic by the American Kennel Club to all other dogs.

Conclusions

Researchers found that the four schemes yielded no significant differences in allergen levels between hypoallergenic dogs and non-hypoallergenic dogs. In homes where the dog was not allowed in the baby’s bedroom (methodology of the study), the allergen level for hypoallergenic dogs was slightly higher compared to allergen levels of non-hypoallergenic dogs.

While researchers acknowledged limitations in their study – the amount of time the dog spent in the baby’s bedroom was not recorded and the size of its sample did not allow looking at specific breeds – they say parents should not rely on dog breeds classified as hypoallergenic.

My Opinion

Though it is no myth that human’s artificial selection of dogs (even starting from wolves) is pretty radical, it appears as though we have not been able to select for allergen production. While dog breeders may believe that these canines produce less allergen, the elimination of this trait is not as straight forward as perhaps they assume.

I think that many people associate dog hair with dog allergen, and this is simply not the case. According to the Asthma and Allergy Foundation of America, allergens are harmless proteins contained in pet dander, which is found in their dead skin, saliva, and urine. Pet dander (containing allergens) is not their fur (although the dander may accumulate in their fur). The point is that most people assume that a dog who sheds less will be better for those allergic in the household, but a dog will still produce dander whether or not they shed.

Until the science bears the claim of hypoallergenic dogs out beyond a placebo-based assumption, it is just another way to spend more money.

More information: The study will be available at http://www.ingentaconnect.com/content/ocean/ajra

[Via PhysOrg]