Do I need to avoid all nuts if I have an allergy to Brazil nuts and hazelnuts?

Managing Tree Nut Allergies: Brazil Nuts and Hazelnuts

You do not need to avoid all tree nuts if you have a confirmed allergy to only Brazil nuts and hazelnuts. Instead, you can safely consume other tree nuts that you are not allergic to, after appropriate testing confirms their safety for you 1, 2.

Understanding Tree Nut Cross-Reactivity

Tree nuts have varying degrees of cross-reactivity based on their botanical relationships:

• High cross-reactivity groups:

  • Walnut and pecan (family Juglandaceae) - 92% sensitization with 12-37% clinical reactivity 1, 3
  • Cashew and pistachio (family Anacardiaceae) 3
  • Brazil nuts share some cross-reactivity with hazelnuts, cashews, and pistachios 3

• Your specific situation:

  • Having allergies to both Brazil nuts and hazelnuts doesn't automatically mean you're allergic to all tree nuts
  • Clinical cross-reactivity (actual allergic reactions) is much lower than sensitization (positive skin or blood tests) 1

Recommended Approach

1. Consult with an allergist for proper evaluation of your specific allergies

2. Undergo appropriate testing:

   • Skin prick testing (SPT) or specific IgE blood testing for other tree nuts
   • Oral food challenges under medical supervision for nuts with negative test results

3. Safe consumption of tested nuts:

   • Research shows that patients with allergies to specific nuts can often safely consume other tree nuts 4
   • In one study, patients with peanut allergies who had negative SPT to macadamia, pine nut, and coconut successfully passed food challenges to these nuts 4

Practical Management Tips

• Label reading: Always check food labels for Brazil nuts and hazelnuts
• Cross-contamination: Be cautious of products that may contain traces of your allergen nuts
• Emergency preparedness: Carry epinephrine auto-injector if prescribed by your allergist
• Restaurant precautions: Inform staff about your specific nut allergies when dining out

Important Caveats

• The current standard practice has been to recommend avoidance of all tree nuts when one tree nut allergy is diagnosed 5, but this is evolving as more research becomes available
• The NIAID guidelines suggest that patients at risk for developing food allergies do not need to limit exposure to foods that may be cross-reactive with major food allergens 1
• Individuals with a history of anaphylaxis should be particularly cautious and follow their allergist's specific recommendations 2

Bottom Line

While complete avoidance of all tree nuts has been the traditional recommendation, current evidence suggests a more nuanced approach. With proper testing and medical supervision, you may be able to safely include other tree nuts in your diet despite having allergies to Brazil nuts and hazelnuts 4, 6. This can significantly improve your quality of life by allowing for a less restricted diet.