Racial, Ethnic, and Socioeconomic Differences in Food Allergies in the US

Question  What is the national distribution of food allergies among all US individuals across race, ethnicity, and socioeconomic groups?

Findings  In this survey study of 51 819 households, Asian, Black, and Hispanic individuals were more likely to report having food allergies compared with White individuals. The prevalence of food allergies was lowest among households in the highest income bracket.

Meaning  This study suggests that racial, ethnic, and socioeconomic differences in the prevalence of food allergies exist and are evident in clinical outcomes such as food allergy–related emergency department visits and epinephrine autoinjector use.

Importance  Food allergies affect approximately 8% of children and 11% of adults in the US. Racial differences in food allergy outcomes have previously been explored among Black and White children, but little is known about the distribution of food allergies across other racial, ethnic, and socioeconomic subpopulations.

Objective  To estimate the national distribution of food allergies across racial, ethnic, and socioeconomic groups in the US.

Design, Setting, and Participants  In this cross-sectional survey study, conducted from October 9, 2015, to September 18, 2016, a population-based survey was administered online and via telephone. A US nationally representative sample was surveyed. Participants were recruited using both probability- and nonprobability-based survey panels. Statistical analysis was performed from September 1, 2022, through April 10, 2023.

Exposures  Demographic and food allergy–related participant characteristics.

Main Outcomes and Measures  Stringent symptom criteria were developed to distinguish respondents with a “convincing” food allergy from those with similar symptom presentations (ie, food intolerance or oral allergy syndrome), with or without physician diagnosis. The prevalence of food allergies and their clinical outcomes, such as emergency department visits, epinephrine autoinjector use, and severe reactions, were measured across race (Asian, Black, White, and >1 race or other race), ethnicity (Hispanic and non-Hispanic), and household income. Complex survey-weighted proportions were used to estimate prevalence rates.

Results  The survey was administered to 51 819 households comprising 78 851 individuals (40 443 adults and parents of 38 408 children; 51.1% women [95% CI, 50.5%-51.6%]; mean [SD] age of adults, 46.8 [24.0] years; mean [SD] age of children, 8.7 [5.2] years): 3.7% Asian individuals, 12.0% Black individuals, 17.4% Hispanic individuals, 62.2% White individuals, and 4.7% individuals of more than 1 race or other race. Non-Hispanic White individuals across all ages had the lowest rate of self-reported or parent-reported food allergies (9.5% [95% CI, 9.2%-9.9%]) compared with Asian (10.5% [95% CI, 9.1%-12.0%]), Hispanic (10.6% [95% CI, 9.7%-11.5%]), and non-Hispanic Black (10.6% [95% CI, 9.8%-11.5%]) individuals. The prevalence of common food allergens varied by race and ethnicity. Non-Hispanic Black individuals were most likely to report allergies to multiple foods (50.6% [95% CI, 46.1%-55.1%]). Asian and non-Hispanic White individuals had the lowest rates of severe food allergy reactions (Asian individuals, 46.9% [95% CI, 39.8%-54.1%] and non-Hispanic White individuals, 47.8% [95% CI, 45.9%-49.7%]) compared with individuals of other races and ethnicities. The prevalence of self-reported or parent-reported food allergies was lowest within households earning more than $150 000 per year (8.3% [95% CI, 7.4%-9.2%]).

Conclusions and Relevance  This survey study of a US nationally representative sample suggests that the prevalence of food allergies was highest among Asian, Hispanic, and non-Hispanic Black individuals compared with non-Hispanic White individuals in the US. Further assessment of socioeconomic factors and corresponding environmental exposures may better explain the causes of food allergy and inform targeted management and interventions to reduce the burden of food allergies and disparities in outcomes.

Food allergies (FAs) affect an estimated 8% of children and 11% of adults in the US.1,2 Individuals with an FA may experience FA-related economic burden, lower health-related quality of life, and increased risk of comorbid atopic conditions (ie, eczema, asthma, and/or allergic rhinitis).3 However, the distribution of FA burden may vary across different racial, ethnic, and socioeconomic strata.4,5

The prevalence of self-reported FAs has been increasing in recent decades, especially among non-Hispanic Black (hereafter, Black) children.6 Black children have been reported to have higher rates of FAs compared with non-Hispanic White (hereafter, White) children in the US.7,8 In the 2007-2010 National Health and Nutrition Examination Survey (NHANES), 8.1% of Black children had parent-reported FAs compared with 6.3% of White children and 5.2% of Hispanic children.9 Black children also often had higher food-specific immunoglobulin E (IgE) levels.10-12 In a Boston-area birth cohort study, Black children were reported to be more likely to be sensitized to any food allergens and multiple food allergens compared with White children.13 Less is known about racial differences in FAs among adults, although the limited available evidence suggests that the differences reported in pediatric samples may also exist among adults.14 The NHANES sensitization data from 2005-2006 suggested that serologically defined FA to peanut, egg white, cow’s milk, and shrimp was more common among Black children and adults.12 These study findings and others, compiled using medical record review and random digit dial survey methods, concluded that Black children and adults have higher rates of seafood allergy compared with other races and ethnicities.4,15,16

Despite a growing body of literature on racial differences in FA prevalence and phenotypes between Black and White populations, there remains a paucity of population-based data on FA burden among other races and ethnicities in the US across all age groups—particularly within the past decade. In addition, although a complex interplay between race and socioeconomic factors exists, these social determinants of health remain underexplored in FA research, to our knowledge.5 Therefore, this study aimed to estimate the distribution of self-reported or parent-reported, “convincing” FAs, reaction severity, and management among individuals of varying racial, ethnic, and socioeconomic backgrounds in the US.

Between October 9, 2015, and September 18, 2016, a population-based survey was developed and administered to 51 819 US households, obtaining parent-reported responses for 38 408 children (≤18 years) and self-reported responses from 40 443 adults (>18 years). Adults completed the survey in English or Spanish via telephone or online. The probability-based sampling methods used included additional coverage of rural and low-income households that are frequently underrepresented in surveys relying on address-based or convenience sampling.1,2 The institutional review boards of Northwestern University and NORC (National Opinion Research Center) at the University of Chicago approved all research study activities. Written and oral informed consent was obtained from all participants. This study followed the American Association for Public Opinion Research (AAPOR) reporting guidelines.

Primary outcome measures included overall pediatric and adult self-reported prevalence of any FA(s) to 9 common, federally regulated food allergens (cow’s milk, hen’s egg, peanut, tree nuts, soy, wheat, sesame, fin fish, and shellfish) among various racial and ethnic groups. Data on physician-diagnosed comorbid atopic conditions, allergic reaction symptoms, severe FAs, emergency department (ED) visits, epinephrine prescriptions, and presence of multiple FAs were also obtained.

Self-reported or parent-reported FA prevalence was calculated for physician-confirmed FAs and “convincing” FAs (self-reported or parent-reported FAs corroborated by a history of symptoms related to an IgE-mediated FA). Self-reported or parent-reported convincing FAs were identified using a stringent algorithm that incorporated a stringent IgE-mediated FA symptom list and reported food allergens. The algorithm was designed to exclude reported FA cases that did not have a clinical food-specific reaction history indicative of a true IgE-mediated FA, such as suspected food intolerances and oral allergy syndrome.1,2 “Physician-confirmed FAs” (hereafter, confirmed FAs) met the criteria for convincing FAs but were also reported as physician diagnosed via confirmatory oral food challenge, skin prick, and/or specific IgE testing. Food allergies were considered severe if stringently defined symptoms were reported that involved 2 or more organ systems as defined: (1) skin and/or oral mucosa system: hives, swelling, lip and/or tongue swelling, difficulty swallowing, or throat tightening; (2) respiratory system: chest tightening, trouble breathing, or wheezing; (3) gastrointestinal system: vomiting; and (4) cardiovascular and/or heart system: chest pain, rapid heart rate, fainting, dizziness, feeling lightheaded, or low blood pressure.1,2

Race is a sociopolitically constructed categorization based on phenotypic indicators. Ethnicity is also a distinct social construct that refers to a shared cultural origin.17 US Census definitions were used for race (ie, American Indian or Alaska Native, Asian, Black or African American, Native Hawaiian or Other Pacific Islander, White, >1 race, or other) and ethnicity (ie, Hispanic or Latino and not Hispanic or Latino).18 Due to sample size limitations, Native Hawaiian or Other Pacific Islander, American Indian or Alaska Native, and those who reported more than 1 race or other race were collapsed into a “more than 1 or other race” category. Therefore, presented estimates are stratified across the following 5 racial and ethnic categories: Asian, Black, Hispanic, White, and more than 1 or other race.

The socioeconomic factors assessed by the survey included household income (1 or other race, 23.6% [18.5%-29.7%]; P = .11) were observed by race and ethnicity.

Patient report of a severe FA reaction history was more common among lower earning households, but again this difference was not statistically significant. In contrast, differences in rates of current epinephrine prescriptions were significantly different by household income, with the lowest earning households least likely to report a current EAI prescription. Report of at least 1 FA-related ED visit (in the last year and lifetime) was most frequent among those with a household income less than $25 000 (last year, 16.2% [95% CI, 12.9%-20.0%]; lifetime, 44.3% [95% CI, 40.6%-48.2%]) (Table 4).

When observing FA severity by insurance type, no significant differences were observed except for the rate of EAI prescription (P