In a new study of 2-year-olds in Boston, black kids were twice as likely as white kids to have an immune response to foods such as peanuts, milk, and eggs, and almost four times as likely to have a “sensitization” to three or more foods.
While food sensitization doesn’t necessarily pose any danger on its own, kids who are sensitized to certain foods are more likely to develop full-blown allergies to them in the future.
“We know that sensitization is not the same thing as food allergy, but what they’re reporting does seem to be consistent with what has been seen in other populations,” said Christine Joseph, an allergy and asthma researcher from the Henry Ford Health System in Detroit who was not involved in the new study.
Other recent studies have hinted at higher rates of food sensitizations or allergies in blacks, she told Reuters Health.
Researchers also looked at the kids’ DNA and found that the more African ancestry it showed, the more likely a child was to have any type of food sensitization, especially to peanuts.
About 38 percent of black kids had a food sensitization, compared to 22 percent of white kids. When the researchers took into account factors like whether or not kids were breastfed and if moms smoked while they were pregnant, the black two-year-olds were more than twice as likely to have a food sensitization.
They were also almost four times as likely to have a detectable immune-system response to three or more of the potential allergens.
That tells researchers that genetics may play a role in how likely kids are to have food sensitizations or allergies. Or, something about different ancestral environments may be playing a role, Kumar said–for example, people from Africa are known to have lower vitamin D levels early in life. Vitamin D has been linked to some aspects of immune function.