"The prevalence of food allergy is growing and probably will continue to grow along with all allergic diseases," says Robert A. Wood, M.D., director of the pediatric allergy clinic at Johns Hopkins Medical Institutions in Baltimore.
Wood says that research over the last three decades indicates that the number of people with allergies is skyrocketing in developed and developing countries, but not in underdeveloped areas.
"The fewer germs in terms of infection and the environment, the more time the immune system has to worry about things like allergens," says Wood. "Recent studies indicate that growing up in a large family or daycare center actually decreases the likelihood of developing an allergy."
Wood, who has had a severe peanut allergy since he was a toddler, says allergic reactions to foods can vary dramatically. "They can range from just a mild rash to very severe swelling in the throat and the airways in the lungs so that there is a complete inability to breathe," he says.
Wood's parents learned of their son's allergy when they introduced him to peanut butter. "The first time I had peanut butter I developed a rash and severe swelling in my face," he says. "I'm extremely allergic. Just being around when a peanut shell is broken and dust is being released is enough to cause a reaction.
"I've had a number of very dangerous reactions," Wood says. "People with a food allergy typically walk around with a little bit of fear all the time. Once it starts, it's a fear-generating experience."