Allergies to certain foods like peanuts, shellfish, wheat products and more are commonly associated with childhood. That's not just because kids tend to be picky eaters – it's been known that many children who are somewhat sensitive to a variety of foods may grow out of that sensitivity and adopt a normal diet in adulthood. However, the opposite could be true as well, as more doctors and researchers are finding.
The New York Times reported that preliminary results out of a new, large study indicate that a significant number of Americans develop allergies to food in adulthood. While the study is still under review, it currently estimates more than half of U.S. adults – 52 percent – report developing a food allergy after reaching 18 years old that they did not experience before.
"More U.S. adults may be developing allergies to certain foods."
This may be somewhat surprising news to doctors and the average patient. While it's estimated that around 5 percent of U.S. adults have some sort of food allergy, that number rises to 8 percent in children. However, researchers have noted in anecdotal reports that adult-onset food allergies may be becoming more common. If the findings of this new study are confirmed, it would shed new light on how we understand and treat these diseases.
Organized by teams of researchers from Northwestern University and the University of Chicago, the new study relied on surveys from 40,477 adults from around the country, and comprise a representative sample of the U.S. population. Researchers found the most common food allergy reported among adults was one to shellfish, impacting almost 4 percent of the total adult population. In order of prevalence, those allergies were followed by peanut allergies at 2.4 percent and tree nut allergies at 1.9 percent.
Trends in food allergies
While kids and adults are often allergic to the same types of foods, if they are allergic at all, there are some remarkable patterns that emerge between the two groups. For example, adults are more likely to experience oral allergy syndrome, in which the body reacts to food the same way it would to airborne pollen, in those who suffer seasonal allergies.
Doctors also explained that they've seen adults whose allergy seemed to be "triggered" by pregnancy or a recent viral infection. This leads some to conclude that adult-onset allergies have some sort of hormonal or genetic component at play, but the link is still not fully understood.
Physicians who spoke with The New York Times were also careful to point out that food allergies and food intolerance were not one and the same, despite their similar symptoms. A bona fide allergic reaction will produce several characteristic symptoms less than two hours after ingesting the culprit substance, and may include:
- Itching
- Hives
- Swelling
- Trouble breathing
- Vomiting
However, a food intolerance may include these same symptoms but won't present itself until a day later. Intolerance to food is a medical condition even less understood than food allergies, but some evidence suggests it may be a more common affliction.
No matter if patients develop a true allergic reaction or one more indicative of an intolerance, the best course of action is generally the same. If the reaction is relatively minor, doctors recommend taking medications like Benadryl to reduce discomfort temporarily. But until they visit an allergist, it may not be wise to eliminate the suspect food entirely, unless the reaction is particularly severe. In that case, patients should seek treatment and have epinephrine injections on hand at all times.
