As if suffering from an allergy isn't bad enough, many people plagued by allergies also have to sort out lots of conflicting evidence and erroneous advice. To set the record straight, here are some of the most common myths about allergies — the facts that debunk them.

Myth: Allergies are psychosomatic.
Allergies are very real — in some cases, potentially life-threatening — rooted in heredity and the environment, yet the mind plays a significant role in their behavior and emotions can trigger allergic reactions.

"Allergy straddles the mind-body border," explains Dr. Andrew Weil, a Harvard-trained physician who is a leading authority on alternative medicine.

"Emotional stress can precipitate allergic reactions, and relaxation techniques can moderate them. A person who is strongly allergic to roses, for example, may react to the sight of a plastic rose, demonstrating the involvement of the mind and the brain." Dr. Weil advocates hypnotherapy to lessen or even prevent allergic reactions.

Myth: Children outgrow allergies.
Children are ten times more likely than adults to have food allergies. Some researchers believe that as a person's gastrointestinal system develops, it gets better at blocking the absorption of components that trigger food allergies. Over time, children typically outgrow allergies to cow's milk, eggs, wheat, and soybean products. However, allergies to peanuts, tree nuts, fish, and shellfish can be lifelong. And some children will outgrow one allergy only to develop another.

Myth: Allergies aren't life-threatening.
Although it rarely happens, allergies can kill. Some people have such an extreme sensitivity to a particular substance that the allergen can trigger an episode known as an anaphylactic shock. A sudden, potentially fatal reaction, anaphylactic shock lowers blood pressure, swells the tongue or throat, and constricts the airways of the lungs, making it difficult to breathe.

Such a reaction requires immediate medical attention. Anaphylactic shock is most often triggered by a food or drug, but it can also result from an insect sting or even, rarely, from immunotherapy for an allergy. People with a history of severe allergic reactions should always carry a pre-loaded syringe of epinephrine (a synthetically produced form of the hormone adrenaline), which can be administered in an emergency.

Myth: People who are allergic to pets are allergic to their fur.
A dog may be a man's best friend, but not if the man is among the estimated 10 to 15 percent of the population that suffers from pet allergies. The allergen is a specific protein produced not in the animal's fur, but primarily in its skin and — a lesser extent— urine and saliva.

As the animal is petted or brushed, or as it rubs up against furniture or people, microscopic flakes of skin (called dander) become airborne. Since all cats and dogs have skin, there are no nonallergenic breeds.

However, since short-haired pets have less hair to shed, they send less dander into the air, so are preferable for those with pet allergies. Dogs are half as likely to cause allergic reactions as cats, but if you're allergic to furry animals, the only no-risk pets are fish and reptiles.