It's time to dispel some allergy myths that I often encounter:

Hypoallergenic dogs. Is your child allergic to dogs, but really wants one as a pet? Unfortunately, there is no such thing as a hypoallergenic dog. At some point the notion was put forth, possibly by dog breeders, that certain short-haired breeds were hypoallergenic because they had hair, not fur. Another perpetrated myth is that you can become sensitized and therefore not allergic to your own pet, while still having symptoms when you're around other dogs.

There is no evidence to support either of these theories. The proteins that cause people to react to dogs are present in all dogs, albeit possibly in varying amounts. If you do become tolerant to these proteins where you no longer have symptoms, your tolerance will be to all, not just one or some dogs. Some breeds do exhibit slightly more allergenic response on analysis, but it's not a very significant difference compared to other dogs.

Despite reports to the contrary, the Obama family's Portuguese water dog Bo is not "hypoallergenic." So, while allergists hear many anecdotes about hypoallergenic dogs, there is little scientific evidence to support this.

Toxic mold. A decade ago, babies in Ohio died from pulmonary hemorrhage, which is quite rare. At the time, the infants' deaths were thought to be caused by so-called toxic mold found in their homes. This claim was subsequently refuted. Although some molds contain toxins, the term toxic mold is a misnomer. Black mold can certainly trigger an allergenic response and asthma, but in order for a child to experience toxic effects, they would have to either ingest the mold or directly inhale it on a 24-7 basis, in concentrations rarely encountered in real life.

Furthermore, there is no evidence that mold causes vague symptoms such as memory loss, confusion or difficulty concentrating. If you have mold, clean it up with bleach and fight conditions that favor mold growth, such as high humidity and water leaks.

Allergies cause autism. Although the jury is still out on the relationship between the immune system and autism, there is presently no evidence linking allergies to autism – either in a child with allergies or a mother affected by allergies with a child in utero.

Autism is a very hard diagnosis to receive and parents are looking for a reason why it happened, but we do them a disservice when we point towards false leads and junk science. For example, the vaccine-autism connection was refuted when the author of a controversial paper (Andrew Wakefield) was found to have fabricated data in order to make the correlation. Even though the study was discredited, it resulted in vaccination rates going down and a resurgence of measles and whooping cough.

Allergies cause ADHD. There are also unsupported claims linking allergies – food allergies in particular – with ADHD. People will go to the lengths of having special and expensive lab tests done to determine a child's Immunoglobulin G (IgG) levels in relation to certain foods or food additives. Anecdotal reports of reactions to foods such as "It makes him so hyper!" fuel the pursuit of a cause. In fact, high IgG levels associated with foods may be erroneously reported to the parent as "dangerous" and to be avoided when there is absolutely no scientific basis for the assertion and no correlation with a child's allergies.

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