Peanuts are not actually a true nut, they are a legume. But the proteins in peanuts are similar in structure to those in tree nuts. For this reason, people who are allergic to peanuts can also be allergic to tree nuts, such as almonds, Brazil nuts, walnuts, hazelnuts, macadamias, pistachios, pecans, and cashews.
Being extra safe, it might be a good idea to avoid tree nuts if you’ve been diagnosed with a peanut allergy (and to avoid peanuts if you’ve been diagnosed with a tree nut allergy). That’s because the nuts might have been processed together.
What Happens With a Peanut or Nut Allergy?
Reactions to foods, like peanuts and tree nuts, can be different. It all depends on the person – and sometimes the same person can react differently at different times. Some reactions can be very mild and involve only one system of the body, like hives on the skin. Other reactions can be more severe and involve more than one part of the body. Most reactions last less than a day and affect any of these four systems: Skin, Gastrointestinal, Respiratory, and Cardiac.
In really bad cases, peanut and tree nut allergies can cause a condition called anaphylaxis. Anaphylaxis is a sudden, potentially life-threatening reaction that, in addition to the symptoms mentioned above, can make someone’s airways swell and blood pressure drop. As a result, the person may have trouble breathing and could lose consciousness.
In the few cases when people do react to airborne particles, it’s usually in an enclosed area (like a restaurant or bar) where lots of peanuts are being cracked from their shells. Although some people outgrow certain food allergies over time (like milk, egg, soy, and wheat allergies), most peanut and tree nut allergies are lifelong.
Peanut allergy is usually diagnosed by the history of reacting to an exposure. This may be confirmed by a blood or skin test. Of note, the history is the critical factor, and once you have been diagnosed the condition is most likely permanent. Blood tests can often return to negative after months of avoidance even though the allergy persists. Remember peanut and tree nut allergies are lifelong in most people.
The only real way to treat a peanut or tree nut allergy is to avoid peanuts and tree nuts. Avoiding nuts means more than just not eating them. It also means not eating any foods that might contain peanuts or tree nuts as ingredients. The best way to be sure a food is nut free is to read the label. Manufacturers of foods sold in the US have to state on their labels whether foods contain peanuts or tree nuts. Check the ingredients list first. After checking the ingredients list, look on the label for phrases like these:
“may contain nuts”
“produced on shared equipment with peanuts or nuts”
“produced in a facility that also processes nuts”
People who are allergic to nuts also have to avoid foods with these statements on the label. Although these foods might not use nut ingredients, the warnings are there to let people know the food may contain traces of nuts. That can happen through something called “cross-contamination”, when nuts get into a food product because it is made or served in a place that uses nuts in other foods.
Always proceed with caution even if you are used to eating a particular food. Even if you have eaten a food in the past, manufacturers sometimes change their processes – for example, switching suppliers to a company that uses shared equipment. And two foods that seem the same might also have differences in their manufacturing.
Here are some other precautions you can take:
Be on the watch for cross-contamination that can happen on kitchen surfaces and utensils – everything from knives and cutting boards to the toaster. Make sure the knife another family member used to make a peanut butter sandwich is not used to butter your bread and that nut breads are not toasted in the same toaster you use. You may decide to make your home entirely nut free.
Avoid cooked foods you did not make yourself – anything with an unknown list of ingredients.
Tell everyone who handles the food you eat, from relatives to restaurant wait staff, that you have a nut allergy. If the manager or owner of a restaurant is uncomfortable about your request for peanut – or nut-free food preparation, do not eat there.
Make school lunches and snacks at home where you can control the preparation.
Be sure your school knows about your allergy and has an action plan in place for you.
Keep rescue medications (such as epinephrine) accessible at all times. Always keep a pair of current Epinephrine auto-injectors on hand. Seconds count during an episode of anaphylaxis.
Wearing a Medical alert bracelet or jewelry so other people, such as rescue personnel, are aware of your peanut or tree nut allergy.
Managing Serious Reactions
If someone is diagnosed with a life-threatening peanut or tree nut allergy (or any kind of life-threatening food allergy), the doctor will want that person to carry an epinephrine auto-injector in case of an emergency. Epinephrine comes in an easy-to-carry container about the size of a large marker. It is easy to use, and the doctor or allergy nurse will show you how to use it. These do expire, and up to 35% of patients with a reaction may require a second injection. Once you have been diagnosed with peanut allergy, you should always keep a pair of auto-injectors on hand.
Keeping epinephrine on hand at all times should be just part of your action plan for living with a peanut or tree nut allergy. It is also a good idea to carry an over-the-counter antihistamine, such as Benadryl, as this can help treat mild allergy symptoms. Use the antihistamine in addition to – not as a replacement for – the epinephrine shot in life-threatening reactions.
Living with allergies can seem hard at times. But as more and more people are diagnosed with food allergies, businesses and individuals are increasingly aware of the risks people with food allergies face.