Allergy Myths Revealed

Experts dispel misconceptions about allergy causes and remedies.

April 30, 2008 — -- The buds and blossoms of spring are longed for, colorful additions to the gray, muted palette of a seemingly endless winter -- at least that appears to be the perspective of many Americans.

But for a growing number in the United States who suffer from seasonal allergies, the spring bloom and resulting airborne storm of yellow-green pollen flecks can be the bane of their existence.

It's estimated that nearly 17 million visits to the doctor's office each year are due to allergic rhinitis, more commonly known as seasonal allergies.

Other types of allergies are also on the rise.

More than 12 million Americans -- or roughly one in 25 -- has a food allergy, including 3 million children, or roughly one in 17 children younger than 3, reports the Food Allergy and Anaphylaxis Network.

The ABC News OnCall+ Allergy section compiled dozens of questions and answers from the nation's top allergy experts on topics including seasonal allergies, food allergies, bug stings and drug reactions.

During the research process, several debatable explanations and remedies emerged. Below you'll find five of the most interesting allergy-related declarations and an analysis of whether they're grounded in reality or just plain bunk.

Fact or Myth? You can't develop allergies as an adult.

Answer: Myth

While many allergies start in childhood, even adults can become allergic to things they weren't allergic to before, according to Dr. Rohit Katial, director of the Weinberg Clinical Research Unit of National Jewish Medical and Research Center.

"There's a feeling that allergies only exist in children and then persist into adulthood. But we frequently see patients that have done well most of their lives and then as an adult they do develop allergies," said Katial, a participant in the ABC News OnCall+ Allergy section.

An allergy could be triggered in an adult because of a newly introduced allergen to which there was no prior exposure. For example, moving from the West Coast to the East Coast might bring on an allergy to ragweed, which thrives in the Northeast. Or, if you did not have a pet growing up, a new dog or cat could trigger an allergy.

Alternatively, some people simply become more sensitive to common allergens, such as pollen, dust mites and molds as they grow older.

Adults who come in with the symptoms will undergo similar testing to that done with potentially allergic children.

"If an adult comes in with symptoms that are typical for seasonal allergies, they should be evaluated to see what they're sensitive to, and again, appropriately treated depending on what the allergen is and given advice regarding environmental precautions and the appropriate medications," said Katial. "Clearly, one can develop both allergies and asthma as an adult and it doesn't have to be just in children," he said.

Fact or Myth? Eat the local honey and you won't get seasonal allergies.

Answer: Myth

There may be a (pollen) grain of truth to the idea behind it, but eating honey and the pollens it's made from won't fix your seasonal allergies.

"The notion is that pollen causes allergy, and honey is made from pollen. Perhaps if you took the pollen and ingested it … then it might somehow build up a tolerance," said Douglas Leavengood, an allergist at Gulf Coast Asthma and Allergy in Biloxi, Miss.

The problem with that thinking, said Leavengood, is that the pollens creating allergy problems aren't the ones bees use for honey.

"It's the tree, grass and weeds that are the allergy pollens. They broadcast [their pollen]," he said.

The pollens bees use in honey are the heavy, sticky pollens from flowers that rely on bees to spread it so the plants can reproduce.

"The pollen the honey is made out of is not the pollen that causes the allergies. It's not tree pollen and it's not grass pollen," said Leavengood. "As far as allergy goes, it's just the wrong type of pollen."

Fact or Myth? Eating allergenic foods during pregnancy/breast-feeding can give allergies to my child.

Answer: Possibly a Fact

This one is still up in the air.

"There's a lot of controversy here," said Dr. David Resnick, director of the Allergy and Immunology Division at New York Presbyterian Hospital.

There's no strong evidence to support the theory that a child will develop allergies after early exposure to allergens because of the mother's diet during pregnancy or while breast-feeding, but it's a possibility that may need to be researched further.

"Food allergens do cross the placenta and into the breast milk," said Michael Daines, a pediatric allergist at the University of Arizona and expert for the ABC News OnCall+ Allergy section. "There is some small benefit to avoiding the very allergenic foods during pregnancy and lactation."

On the other hand, eating a regular diet could stem an allergy. Resnick pointed out that in Israel, mothers do not avoid peanuts or peanut butter and there are fewer peanut allergies in that country, though there is no strong research to support a direct relationship.

By contrast, American mothers who already have children with allergies might be advised to avoid specific foods during a later pregnancy, based on the theory that the baby will not become allergic this way. However, peanut allergies in the United States have been rising dramatically in the last decade.

So while no strong evidence exists that eating these foods during pregnancy and breast-feeding causes problems, more concerned mothers can take that extra step.

Fact or Myth? Cow's milk is behind the rise in allergies in Western nations.

Answer: Myth

This theory about cow's milk looks to be, well, bull.

"I've not seen any studies that would suggest that's a viable option," said Wesley Burks, chief of the Division of Pediatric Allergy and Immunology at Duke University Medical Center.

Burks says that while many explanations have been offered for why allergies are rising in industrialized nations but not in developing ones, the milk theory is among the weakest.

To Burks, one explanation does stand out, however.

"There aren't great reasons for [the increase in allergies] now, other than the hygiene hypothesis," he said. "The theory would be that we're living too clean a lifestyle, and that's what causes the increase in allergic disease."

"There's some good evidence from Eastern European studies," said Burks. "Children that grew up with farm animals … there's significantly less allergic disease in those children."

So while drinking cow's milk may not cause your allergies, hanging around cows as a child might just keep allergies away.

Fact or Myth? Some foods only cause allergic reactions when eaten raw.

Answer: Fact

This one is true, according to Dr. Andrew Liu, director of pediatric allergy and immunology at National Jewish Medical and Research Center in Denver.

"Some people have allergic symptoms in their mouth when they eat certain fruits and vegetables that are fresh but not when they're cooked. And that's very interesting -- we call that oral allergy syndrome," Liu said.

The reason, Liu explained, is that cooking destroys the problematic allergens in these foods.

"In the fresh state, they cause allergic symptoms usually limited to the mouth, but sometimes it can also affect breathing," he said. "But when those fruits or vegetables are cooked, then the allergens are broken down, and they no longer cause symptoms."

This is also the case with food oils. A person with a soy, corn or safflower allergy is unlikely to be allergic to soy, corn or safflower oils because the processing and purification breaks down the allergens. However, because peanut oil is typically less processed, it is still a potential allergen for a person with peanut allergies.

ABC News' Radha Chitale contributed to this report.