What is a food allergy?
Patients often ask me – “what is a food allergy?” Or “what is a food sensitivity?” Is that the same as a food intolerance? The word “allergy” is derived from the Greek word meaning “altered reaction”. These reactions can include headaches, nausea, vomiting, hives, migraines or difficulty breathing with exposure to the allergen. Some patients, however, can have no overt symptoms, but suffer a general malaise possibly due to an internal inflammatory reaction. The substance which provokes a reaction is called an allergen. There are many allergens we can be exposed to, the most famous ones being house dust, dog dander, and tree pollen, just to name a few. More often than not, a patient can have “hidden” food allergies, and these are known as IgG food sensitivities, which will be explained in the remainder of the article. Food sensitivities and intolerances are very similar, the main difference being that a sensitivity can produce little to no overt reaction, and an intolerance produces a reaction in the digestive tract. A food allergy is seen when the food proteins are recognized by the immune system as being harmful like a virus or bacteria. In my practice, I see dairy, eggs, gluten, pineapple and kidney beans as being the most common offenders.
For most people, the term “allergy” denotes images of itchy eyes, a runny nose, congested sinuses, etc. However, an allergy can affect any organ system, such as the digestive tract, skin or joints. Irrespective of how they present, allergies are common with an estimated 30 to 50% of the population affected. Allergies can begin or resolve at any point in life – patients can grow out of allergies or develop allergies at any time.
Having allergies impacts a person’s activities of daily living, and can cause low work productivity. Some individuals have a serious food allergy, such as celiac disease. Depending on the severity of this disease, associated treatments might be medications or even surgery.
A food allergy has a classic immune response with numerous IgE immediate hypersensitivity antibodies to a specific food protein being released. In these cases, the immune system thinks that the food protein is similar to a harmful pathogen, such as a bacteria or virus, and mounts an immediate immune response. With repetitive exposure, the immune system produces large quantities of histamine which adversely affect the lungs, heart, skin and gastrointestinal tract. If the histamine release exceeds a certain point, the person could suffer a fatal anaphylactic reaction.
In the middle, between the food sensitivities and food allergies, there are food intolerances, wherein a larger amount of food has to be consumed in order to produce symptoms. The most common example of this would be lactose intolerance, where the enzyme lactase is deficient. When taken in smaller quantities, most people with this intolerance can handle the lactose, especially when the lactose is combined with other foods. However, when larger quantities are consumed, a person will suffer from abdominal pain, diarrhea, flatulence, and bloating. Food intolerances can be considered a milder form of an allergy, even though there is no immediate allergic response like the classic food allergy – they tend to be delayed, sometimes up to 72 hours.
The top 10
Here is a list of the top 10 foods I see showing up on testing:
- Green/Kidney/Navy Beans
If you are curious about which foods will be beneficial to your body, versus which foods can create an inflammatory reaction, a simple blood test at the clinic to detect these antibodies. Based on the results of the blood test, a treatment plan will be prepared to address the “damage” that the food intolerances have formed in the body. With time, the patient’s body recovers and the patient feels better overall. Feel free to contact me if you have questions, and I look forward to helping you in the future.
Dr. Sanjay Mohan Ram, B.Sc. (Hon.), N.D.