More than a quarter of Americans, both children and adults, have at least one allergic condition, according to two new reports from CDC's National Center for Health Statistics (NCHS).

Allergies grow in prevalence in the US

For both reports, NCHS researchers used data from the 2021 National Health Information Survey (NHIS) to assess the prevalence of seasonal allergies, eczema, and food allergies among both children and adults.

NHIS is a nationally representative survey of U.S. households that is conducted continuously throughout the year. Because of the pandemic, roughly 60% of both the sample child and sample adult interviews were conducted over the phone instead of in person like usual.

Allergies among children

According to the researchers, just over a quarter (27.2%) of children in the United States had at least one allergic condition in 2021. Seasonal allergies affected 18.9% of children, eczema affected 10.8%, and food allergies affected 5.8%.

Overall, the researchers noted that the prevalence of allergies among children has increased over the last decade. In 2011, the rate of respiratory allergies among children was 17%, the rate of skin allergies was 12.5%, and the rate of food allergies was 5.1%.

However, they cautioned that "[e]stimates for allergy prevalence are not directly comparable to those calculated using data before the 2019 redesign of the NHIS questionnaire due to wording changes."

When looking at the different allergic conditions, the researchers found that seasonal allergies among children varied by sex, age, and race/ethnicity. In general, boys were more likely to have a seasonal allergy than girls, and children ages six and older were more likely to have a seasonal allergy than children ages five and younger.

Black and white children were also more likely to have a seasonal allergy than Hispanic or Asian children.

When it came to eczema, boys and girls were equally likely to have the condition. However, eczema was most common among children ages six to 11 and Black children.

Although rates of food allergies were largely similar between boys and girls, these rates increased with age, with children ages 12 to 17 having the highest prevalence at 7.1%. Black children were also more likely to have a food allergy than white and Hispanic children.

Allergies among adults

Adults had a slightly higher prevalence of allergies than children, with 31.8% of adults reporting at least one allergy in 2021. In total, 25.7% had seasonal allergies, 7.3% had eczema, and 6.2% had food allergies.

Women were more likely than men to have seasonal allergies (29.9% vs. 21.1%, respectively). In addition, the highest rates of seasonal allergies occurred among adults ages 45 to 64 (27.9%), while the lowest rates occurred among adults ages 75 and older.

White adults were the most likely to have seasonal allergies, followed by Black adults. Hispanic and Asian adults had the lowest rates of seasonal allergies.

Women were more likely to have eczema than men (8.9% vs. 5.7%). In general, rates of eczema decreased with age, with adults ages 75 and older having the lowest rates at 5.5%.

Hispanic adults were less likely to have eczema compared to white adults, Black adults, and Asian adults. Although Black adults were more likely to have eczema than Asian adults, the difference between Black and white adults was not significant.

Women also had higher rates of food allergies than men (7.8% vs. 4.6%, respectively). Food allergies were also most prevalent among adults ages 45 to 64 (6.7%), followed closely by those ages 18 to 44 (6.6%).

Black adults also had higher rates of food allergies than any other racial or ethnic group at 8.5%

(Short, MedPage Today, 1/26; Zablotsky et al., NCHS data brief, accessed 1/31; Ng/Boersma, NCHS data brief, accessed 1/31)