What’s unique about this study is that it was looking at adults. Studies before now primarily looked at children.

Prevalence and Severity of Food Allergies Among US Adults, JAMA Network, 4 January 2019

Conclusions: These data suggest that at least 10.8% (>26 million) of US adults are food allergic, whereas nearly 19% of adults believe that they have a food allergy.

Nearly half of food-allergic adults had at least 1 adult-onset food allergy, and 38% reported at least 1 food allergy–related emergency department visit in their lifetime.

So, over 10 million adults may have acquired their allergy later in life.

These were the most common food allergens among US adults:

• Shellfish (affecting an estimated 7.2 million adults)
• Milk (4.7 million adults)
• Peanut (4.5 million)
• Tree nut (3.0 million)
• Fin fish (2.2 million)
• Egg (2.0 million)
• Wheat (2.0 million)
• Soy (1.5 million)
• Sesame (0.5 million)

That shellfish allergy, the most common, actually begins more often in adulthood.

Here’s the thing … millions of adults are fine, living their lives, no problem, then one day they eat a shrimp or an almond or some peonut butter and have a reaction so bad they need epinephrine to survive.* What’s going on? Why is there an increase in these allergies? (“Studies suggest that rates of food allergy–related emergency department visits may be increasing among children and young adults.”)

* “All patients diagnosed with a food allergy should be prescribed epinephrine because of the inability to accurately and reliably estimate the severity of future allergic reactions.”

A food intolerance, like lactose intolerance, is not a food allergy:

Pysical reactions to certain foods are common, but most are caused by a food intolerance rather than a food allergy. A food intolerance can cause some of the same signs and symptoms as a food allergy, so people often confuse the two.

A true food allergy causes an immune system reaction that affects numerous organs in the body. It can cause a range of symptoms. In some cases, an allergic food reaction can be severe or life-threatening. In contrast, food intolerance symptoms are generally less serious and often limited to digestive problems.

We really need to figure out why so many people, young and old, are developing food allergies. But, remember this?

Generic drugmaker Mylan obtained the rights to sell EpiPen in 2007. Since then, Mylan has increased the list price from $94 to $609, researchers report in JAMA Internal Medicine.

If I was a drug company, I would sure salivate over 26 million Americans needing my drug, at least yearly, for the rest of their lives. (What’s 26 million times $609?)

Here’s a brief news summary of the study:
One In 10 Adults In US Has Food Allergy, But Nearly 1 In 5 Think They Do