Q: Should I introduce tree nuts my daughter is not allergic to – such as pistachios and almonds – into her diet? How could I do that without risking cross-contact with her big allergens, which are walnut and pecan? Would there be much benefit in trying to include such foods?
Dr. Sicherer: There are practical issues to consider with this question. Age is a factor, since many nuts are choking hazards for young children.
Cross-contamination is another issue. There are popular products with almonds and hazelnut that can be purchased without worries about cross-contact, while choices are much more limited with cashew, pistachio, Brazil nut, etc.
Some families will rinse off nuts purchased individually. Other families take the approach of “no nuts” so as to avoid confusion, misidentification, and cross-contact with the ones to be avoided.
There are theoretical issues as well regarding your question about benefits. Recent guidelines suggest that allergy-prone infants without a peanut allergy eat infant-safe forms of peanut early to avoid becoming allergic.
This approach for peanut raises the question as to whether children with one nut allergy should purposefully eat the nut(s) to which they are not allergic.
There are no studies to inform us on the best approach, so making recommendations to do this carries potential consequences that may include increasing, decreasing or having no effect on allergy risks. At this point we just do not know.
The theoretical reason to have your child eat other nuts has to be considered against practical issues, and not only cross-contact. The LEAP peanut study had infants eat a large serving of peanut three times a week until the age of 5. Translating that to multiple tree nuts presents a practical problem for a family.
This is clearly a complex issue that needs to be discussed with your allergist on an individual basis. Practical and theoretical concerns should be discussed in the context of your child’s current allergies, family dietary choices, personal preferences and other factors.
Given our state of knowledge and practical considerations, there are no wrong decisions.
Dr. Scott Sicherer is a practicing allergist, clinical researcher and professor of pediatrics. He is Director of the Jaffe Food Allergy Institute and Chief of Pediatric Allergy and Immunology at the Icahn School of Medicine at Mount Sinai in New York. He’s also the author of Food Allergies: A Complete Guide for Eating When Your Life Depends On It.Submit a Question View all posts by this medical expert.