A food allergy is an adverse immune response (typically IgE-mediated) triggered by a specific food. Food allergy affects between 3% and 8% of people.
The researchers sought to determine the prevalence of food allergy and intolerance documented in the electronic health records (EHRs). They used allergy data from a large health care organization's EHR (Division of General Medicine and Primary Care, Brigham and Women's Hospital, Boston, Mass) between 2000 and 2013.
There is a possible error right the at beginning of abstract: "Data were validated using radioallergosorbent test and ImmunoCAP results." Radioallergosorbent test (or RAST) has not been in clinical use in the US for years. I have not seen a RAST test report at least since 2007, while working with tens of thousands of patients. More info here: https://www.foodallergy.org/life-food-allergies/food-allergy-101/diagnosis-testing/blood-tests
Back to the results of the study: Among 2.7 million patients, close to 100,000 patients (97,482, to be exact) 3.6%) had 1 or more food allergies or intolerances.
Food allergy management in 4 steps (click to enlarge the image).
The prevalence of food allergy and intolerance was higher in females (4.2% vs 2.9%) and Asians (4.3% vs 3.6%).
The most common food allergen groups were shellfish (0.9%), fruit or vegetable (0.7%), dairy (0.5%), and peanut (0.5%).
This bring another important point: the term "dairy allergy" should be abandoned and replaced with "milk allergy". The explanation is here: https://www.foodallergy.org/about-fare/blog/know-the-difference-milk-allergy-vs-dairy-allergy-vs-lactose-intolerance
Of the 103,659 identified reactions to foods, 16% were anaphylactic. About 20% of patients with reported peanut allergy had a radioallergosorbent test/ImmunoCAP performed (see above for RAST).
Adverse Food Reactions (click to enlarge the image).
Prevalence of food allergies and intolerances documented in electronic health records. Warren W. Acker et al. JACI,December 2017, Volume 140, Issue 6, Pages 1587–1591.e1