Children who are deficient in vitamin D may be more susceptible to allergies.

Researchers from the Albert Einstein College of Medicine studied blood tests of 6,500 people and their sensitivity to allergens. While no link was found in adults, blood tests revealed children and adolescents with low levels of vitamin D could be linked to sensitivity to 11 of the 17 allergens tested. The study categorized participants between the ages of one to 21 as children.

The study tested environmental allergens including ragweed, oak, dog, and food allergens such as peanuts

Children who had vitamin D deficiency, defined as fewer than 15 nanograms of vitamin D per milliliter of blood, were 2.4 times as likely to have a peanut allergy than children with sufficient levels of vitamin D, defined as more than 30 nanograms of vitamin D per milliliter of blood.

According to and the USDA, the daily recommendation of vitamin D for children and teens is at least 400 International Units (IU). One cup of whole milk contains 100 IU, or 25 percent of a child’s daily recommended intake.

The samples were derived from the National Health and Nutrition Examination Survey, a program of studies designed to assess the health and nutritional status of adults and children across the U.S. One of the blood tests assessed was sensitivity to 17 different allergens by measuring levels of Immunoglobulin E, a protein made when the immune system responds to allergens.

The researchers are unsure why vitamin D could enhance children’s susceptibility to developing allergies but not for adults. One reason may be that most allergic sensitization may happen in childhood.