Nut allergies got you down? A new study may give you food for thought.
Recent research from the American College of Allergy, Asthma and Immunology shows that people who had once tested positive for nut allergies may not actually be allergic to all kinds of nuts.
"Too often, people are told they're allergic to tree nuts based on a blood or skin prick test," says allergist Christopher Couch, MD and lead author of the study. "They take the results at face value and stop eating all tree nuts when they might not actually be allergic." But as it turns out, over half of the study’s participants with recorded nut allergies were able to pass an oral food challenge of tree nuts -- almonds, cashews, walnuts, hazelnuts --without any reactions.
An oral food challenge requires the patient to eat tiny amounts of the food in incremental doses over time followed by observations for any reactions. Oral food challenges are considered the most accurate way to diagnose food allergies. While some participants showed sensitivity to tree nuts through skin pricks or blood tests, these participants had no reactions to oral tests.
Oral food challenges should only ever be conducted under the supervision of a trained, board-certified allergist.
"Previous studies suggested people with a tree nut allergy, as well as those with a peanut allergy, were at risk of being allergic to multiple tree nuts,” said allergist Matthew Greenhawt, MD, chair of the ACAAI Food Allergy Committee and study co-author. “Tree nut allergy should only be diagnosed if there is both a positive test and a history of developing symptoms after eating that tree nut."