An astonishing one in three of us is allergic to something, and approximately half of all allergies are food allergies. So if you have one or suspect you do – whether its to pollen, peanuts, shellfish, milk or wheat – you’re hardly alone.
What is an allergy?
With an allergy , the immune system produces a protein called an antibody to fight off the allergen that’s causing the problem. Allergens are substances present in our environment, normally harmless, but can sometimes trigger an immune response. (Read more on wiki on antibody)
In a ‘classic’ allergy, an antibody called IgE (Immunoglobulin E – wiki) is produced, triggering the release of a chemical, Histamine, that usually causes a rapid, severe reaction such as swelling of the mucous membranes. Mucous membranes are internal linings of those organs which have cavities meant for absorption or secretion, like stomach, nostrils, lips, genitals, and eyelids, etc. (read more on wiki)
More common are allergic reactions involving the IgG antibody. This type can cause a delayed reaction – sometimes called a ‘food intolerance’ – up to 24 hours after exposure to the allergen. While not as obviously dramatic as a classic allergic reaction, a food intolerance can seriously erode your well being. Luckily, its easy to get to grips with.
What are the common symptoms of allergies?
- Swelling inside nose (nasal mucosa)
- Allergic sinusitis 
- Redness and itching in eyes (conjunctiva)
- Sneezing, coughing, constricted air pathways, wheezing and shortness of breath
- Outright attacks of asthma in rare cases
- Feeling of fullness in ears, possibly pain, and impaired hearing
- Skin rashes, such as eczema and hives
- Abdominal pain, bloating, vomiting, diarrhea
Why do people get allergies?
One man’s food is another man’s poison.
This means some of us react to certain foods while others do not. Why this happens is largely shrouded in mystery, but we do have a pretty good idea of why it happens. First, if food is introduced too early into a child’s diet, their immature immune systems can mistake innocuous foods for harmful invaders and set off an immune response to protect them from the ‘attack’. The resulting symptoms are allergic reactions. It’s no coincidence that dairy products and wheat, two of the most common foods fed to the infants (as formula and rusks), cause problems in many of them.
Why do some allergies hit later in life?
Trouble can also hit further along the road. Some adults can eat certain foods for years with no problem, then suddenly start reacting to them. This can happen for a variety of reasons. Perhaps they have eaten too much of a given food – not a rare occurrence these days with wheat, for example. Just think how many people start the day with toast or wheat-based cereal, grab a sandwich for lunch and then settle down to a plate of pasta for dinner!
Also, as we age, our stomach acid levels fall and we tend not to chew and digest our food so well. Our digestive system is meant to break food down into molecules, which can be readily used by the body. Poor digestion, however, means fragments of food can enter the bloodstream, where they’re treated as hostile invaders by our immune system’s scout cells.
The same thing can happen if you have a ‘leaky’ gut, where the intestinal tract lining has become too permeable to do its job properly. Stress, nutrient deficiencies, alcohol and some drugs can all contribute to this condition.
In all these ways, your body can become sensitive to certain foods, and continuing to eat them will mean your body goes on eliciting the same reaction due to its immunological memory.