Nut and peanut allergy: symptoms, risks and what to do
A nut or peanut allergy is an allergic reaction of the immune system to proteins found in nuts or peanuts, which can lead to sudden skin redness, unpleasant itching in the mouth, or difficulty breathing. But what exactly happens in the body during such an allergy? And which types of nuts can trigger allergic reactions? If you want to learn more about nut and peanut allergies and how to manage them, keep reading.
Table of Contents
- What is a nut and peanut allergy?
- What happens during a nut and peanut allergy?
- Are peanuts “nuts”?
- What cross-allergies can occur with nuts and peanuts?
- What are the symptoms of a nut and peanut allergy?
- How is a nut and peanut allergy diagnosed?
- How is a nut and peanut allergy treated?
- Summary
What is a nut and peanut allergy?
A nut or peanut allergy, a form of food allergy, occurs when the immune system mistakenly identifies certain proteins found in various types of nuts and peanuts as harmful invaders. Despite their name, peanuts are actually legumes and not true nuts. The proteins contained in nuts and peanuts are essentially harmless and are consumed by people without allergies without any negative reaction. In individuals with allergies, however, an immune response is triggered. The immune system, which usually serves to protect the body from harmful substances such as bacteria and viruses, incorrectly identifies the proteins in nuts and peanuts as dangerous and initiates a cascade of defense mechanisms, resulting in an allergic reaction (Mayo Clinic, 2022).
The prevalence of nut and peanut allergies varies worldwide, with a notable increase in peanut allergy rates in recent years. Risk factors can include a family history of allergies and early exposure to nuts or peanuts. Nut allergies are therefore more common in children than adults and are also more frequently seen in individuals with other allergic conditions such as asthma or hay fever (Liebermann et al., 2020).
What happens during a nut and peanut allergy?
In the case of a nut or peanut allergy, the immune system identifies the proteins found in nuts and peanuts as a threat. In response to this perceived threat, the immune system produces specific antibodies called immunoglobulin E (IgE).
Upon repeated contact with these proteins, the IgE antibodies bind to the allergens (the allergy-triggering proteins) and cause certain immune cells to release substances such as histamine. These substances lead to a range of symptoms known as allergic reactions.
The severity of these reactions can vary, from mild symptoms such as skin redness and itching to severe symptoms that affect the respiratory system and may trigger anaphylactic shock—a serious and potentially life-threatening allergic reaction (Cleveland Clinic, 2019).
Are peanuts “nuts”?
To avoid nut allergy symptoms, it can be useful to understand how nuts are classified. It is important to note that the general use of the word “nut” in nutrition and everyday language often does not align with its exact botanical definition. Many of the nuts we commonly eat are not technically true nuts in the biological sense. The following classification may help as an overview:
- True nuts: These are botanically considered real nuts. They do not open to release their seed when ripe. Examples include hazelnuts, acorns, chestnuts, and macadamia nuts.
- Tree nuts: These come from trees, but many are not true nuts in a botanical sense. Nevertheless, they are commonly referred to as nuts. Examples include walnuts (actually a drupe), pecans (a drupe), and Brazil nuts (a capsule fruit).
- Drupe seeds: These have a hard “pit” or “stone” in the center containing a seed. Many commonly consumed “nuts” are actually seeds of drupes. These include almonds, pecans, pistachios, and cashew nuts.
- Capsule fruits: These are fruits that contain seeds and open upon ripening to release their seeds.
-
Legumes: These include peanuts, which, despite their name, are not nuts but legumes, like peas and beans.
Source: Raman, 2019
Nuts and peanuts are exceptionally nutrient-dense, containing healthy fats, proteins, vitamins, and minerals. Their unsaturated fats, especially omega-3 fatty acids, can lower cholesterol levels and support heart health. They are also an excellent source of protein and contain B vitamins for energy metabolism, as well as the antioxidant vitamin E. In addition to their nutritional value, the minerals in nuts and peanuts, such as magnesium, zinc, and iron, play vital roles in body functions, including muscle support, blood sugar and blood pressure regulation, immune system enhancement, wound healing, and oxygen transport in the blood (Wilson, 2019).
What cross-allergies can occur with nuts and peanuts?
Cross-reactions are a common phenomenon in food allergies and occur when the immune system cannot distinguish between proteins in different but similar foods. In a nut allergy, cross-reactions can occur both between different types of nuts and between nuts and other foods.
Individuals with a nut allergy may react to one or several types of nuts because the proteins in different nuts can be similar. However, being allergic to one type of nut does not automatically mean that a person is allergic to all other nuts. For example, someone who is allergic to walnuts may be able to eat almonds without issue.
Although peanuts are legumes, they can still cause cross-reactions with other nuts and legumes such as soy. A person who is allergic to peanuts may also react to soybeans. However, it is important to note that not everyone with a peanut allergy is also allergic to soy or other legumes.
It is important to understand that cross-reactions vary significantly from person to person. While some individuals react to a wide range of nuts and legumes, others may only be allergic to a specific type of nut. An allergist can determine which nuts and legumes a person is allergic to through allergy tests and a thorough review of their medical history.
Source: Couch et al., 2017
Want to get clarity for yourself?
The extensive allergy test from Homed-IQ can be a helpful tool in the context of a nut and peanut allergy. It enables you to test for allergic reactions to a wide range of substances, including various types of nuts, from the comfort of your home. With this test, potential allergens can be identified, helping you better understand possible symptoms and take appropriate steps to avoid triggers.
What are the symptoms of a nut and peanut allergy?
The symptoms of a nut and peanut allergy can be grouped according to their severity:
Milder symptoms:
- Itching in the mouth and throat
- Hives or skin redness
- Gastrointestinal issues such as nausea, abdominal pain, or diarrhea
More severe symptoms:
- Difficulty swallowing
- Shortness of breath or wheezing
- Swelling of the lips, tongue, or face
Life-threatening symptoms (anaphylaxis):
- Shortness of breath due to swelling of the airways
- Loss of consciousness or shock
- Rapid heartbeat
If you notice signs of a nut allergy, you should consult a doctor immediately and avoid all nuts and nut-containing products until you receive an accurate diagnosis and appropriate treatment guidelines (Patel & Koterba, 2022).
How is a nut and peanut allergy diagnosed?
Diagnosing a nut or peanut allergy requires a thorough review of the affected person's medical history. In many cases, an accurate diagnosis can only be made through specific tests by a physician. Below are some methods used to diagnose a nut or peanut allergy:
- Medical history: This includes a detailed conversation with the doctor about symptoms, potential triggers, reactions to food, and family history.
- Skin test: In a skin test, the doctor applies a small amount of the allergen (in this case, a nut protein) to the patient's skin. If the person is allergic, a reaction such as redness or swelling will appear at the test site within 20 minutes.
- Blood test: A blood test, also known as an IgE test, measures the amount of immunoglobulin E (IgE) antibodies against nut proteins in the person's blood. A higher IgE level may indicate an allergy.
- Provocation test: In this test, conducted under strict medical supervision, the person is given small amounts of the suspected allergen (in this case, nuts or peanuts) to eat. The amount is gradually increased to observe whether a reaction occurs.
Source: Mayo Clinic, 2023
How is a nut and peanut allergy treated?
Treatment for a nut or peanut allergy primarily aims to control symptoms and prevent serious allergic reactions. There are two main strategies: general preventive measures and the use of medications in emergency situations.
General measures
The most effective way to prevent allergic reactions to nuts and peanuts is to eliminate these foods from the diet entirely. However, this can be challenging since nuts and peanuts are found in many processed foods. Here are some helpful strategies:
- Dietary changes: A nut-free diet is the main treatment strategy. This means avoiding all foods that contain nuts or peanuts.
- Reading labels: It is important to carefully read the labels of all processed foods, as nuts and peanuts are often present in products where one might not expect them. They can be found in salad dressings, spreads, baked goods, granola bars, and many other items.
- Knowing alternatives: For individuals with nut allergies, there are many foods that serve as important alternatives and are rich in vitamins, fats, minerals, and antioxidants. Seeds, such as sunflower or pumpkin seeds, are high in valuable nutrients and unsaturated fats like omega-3 fatty acids. Legumes like lentils and chickpeas are also nutrient-dense and provide healthy fats and proteins. Whole grains, quinoa, and amaranth also supply essential nutrients and antioxidants. Fruits and vegetables—especially dark leafy greens and berries—are rich in vitamins and antioxidants as well. However, keep in mind that even these foods may trigger cross-reactions, so it's important to be cautious and monitor the body's response.
- Communication: It is essential to inform family, friends, colleagues, and school or work environments about the allergy in order to avoid cross-contamination.
Source: Wilson, 2019
Medication and emergency kit
If an allergic reaction occurs despite all precautions, it is crucial to act quickly. An emergency kit is a vital part of managing nut and peanut allergies.
The emergency kit should include detailed instructions on how to respond to an allergic reaction, including when and how to take medications and when to call an ambulance. It should always be easily accessible and may include the following medications:
- Epinephrine auto-injector: Also known as an EpiPen, this medication is used to treat severe allergic reactions. It can be quickly administered and works by suppressing the symptoms of a serious allergic response.
- Antihistamines: These medications can help relieve allergy symptoms by blocking the effects of histamine.
- Corticosteroids: These can help reduce inflammation that may occur during an allergic reaction. They are often used in combination with other medications.
Source: Cleveland Clinic, 2019
Additionally, oral immunotherapy is an option for treating nut and peanut allergies. This is a treatment in which small but gradually increasing amounts of the allergenic food are administered to help the immune system build tolerance. The goal of this therapy is to reduce the severity of allergic reactions upon exposure to nuts and, eventually, to achieve desensitization. Oral immunotherapy is not suitable for everyone and should only be conducted under strict medical supervision, as it can cause severe allergic reactions in some individuals (Sheikh, 2012).
Summary
A nut and peanut allergy is a common food allergy that can occur at any age, though it is more frequent in children. It arises when the body's immune system views specific proteins in nuts and peanuts as threats and triggers an allergic reaction. Symptoms can range from mild to severe and, in extreme cases, be life-threatening. The main form of treatment consists of avoiding nuts and peanuts and using medications and an emergency kit in the event of an allergic reaction.
