Understanding Allergies and Food Allergens

Study Notes

Allergies occur when your body's immune system overreacts to a substance called an allergen. This can cause symptoms like sneezing, itching, watery eyes, rashes, swelling, wheezing, coughing, runny nose, headaches, stomachache, nausea, vomiting, diarrhea, or dizziness. Some common types of allergies include hay fever, food allergies, asthma, drug allergies, and insect stings.

Causes of Allergies

Allergy triggers can be found everywhere—in plants, animals, foods, products, medicines, and even in the air we breathe. They often develop from things you touch, eat, breathe, inject, swallow, or absorb into your skin. Common indoor allergens include dust mites, cockroach parts, animal hair, mold spores, pollen, and pet dander. Outdoor allergens commonly found include tree pollen, grass, ragweed seeds, weed seeds, and pollen grains. Food allergens come from nuts, fruits, vegetables, eggs, milk, fish, shellfish, spices, and other ingredients. Drugs and medical procedures such as vaccinations can also trigger allergic reactions.

Food Allergen Proteins

Food allergies happen because our bodies don't recognize certain proteins found in some foods, seeing them as invaders. These proteins, called allergens, stimulate our immune systems and make antibodies against these foreign substances. When this happens, our bodies release chemicals like histamine which cause most of the signs and symptoms of an allergic reaction. In severe cases, the release of histamine and other substances can lead to anaphylaxis, a life-threatening emergency requiring immediate treatment.

Top 8 Food Allergens

The eight major food allergens identified by the US government are:

Milk
Eggs
Fish
Crustacean shellfish
Tree nuts
Peanuts
Wheat
Soybeans

These foods need to be listed separately if they are added to any product, and manufacturers must list all possible sources of milk, egg, fish, crustacean shellfish, tree nut, peanut, wheat, and soya bean protein present in their products.

Immune System Response to Allergens

When your immune system encounters something it sees as dangerous, it makes proteins called immunoglobulin E (IgE) antibodies. If you have an allergy, these IgE antibodies react with the allergen and cause your cells to produce more histamines, leading to the typical allergy symptoms. For example, if you're allergic to peanuts, eating just one peanut could trigger an immune response, resulting in a range of reactions from mild to severe.

Allergic Reactions

There are two main kinds of allergic reactions - immediate and delayed:

Immediate reactions usually occur within minutes after exposure to an allergen, last less than half an hour, and may involve itchy rash, redness, hives, and fluid-filled blisters.
Delayed reactions typically take hours or days before you notice the allergen is causing problems, but once it starts, they tend to get worse. Not everyone has both quick and slow responses to allergies.

Many people who experience minor discomfort due to allergies do nothing about it. However, others suffer serious reactions, including breathing trouble, hives, and anaphylactic shock. It's crucial to know what might cause your allergies and learn how best to treat them.

Description

Explore the causes, symptoms, and reactions associated with allergies and food allergens. Learn about common allergens like dust mites, pollen, and food proteins, as well as the immune system's response to these triggers.