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Natural Awakenings Naples and Fort Myers

Food Sensitivity Versus Food Allergies

Oct 31, 2023 11:46AM ● By Dee Harris

The immune system reacts in multiple ways that may result in a food allergy, food sensitivity or intolerance. Some reactions to food are an abnormal response in the gut that occurs for many different reasons and at any age.

A food intolerance indicates the body’s lack of an enzyme to break down the food correctly. For example, when an individual with a lactose intolerance consumes milk or ice cream, they will experience cramping and diarrhea because their body does not make enough of the enzyme lactase to break it down. The workaround for this is taking enzymes with the food. Lactose-free milk has had the enzyme added to break down the lactose.

Food Sensitivity

A food sensitivity (IgG) is usually the result of gut permeability, or leaky gut. When food drops through an ultra-permeable lining of the gut, the lymph system looks at the food and decides what belongs and what doesn’t. Certain foods that an individual is used to eating may fall through the lining and get placed on the “doesn’t belong” list. Now the immune system creates antibodies, called IgG, for the proteins in specific foods. These antibodies may lead to inflammation and irritation of not only the gut lining, but may cause systemic issues, as well.  What may amplify the reaction is the production of C3D or its complement. C3D is activated in response and attaches onto the antigen and greatly increases inflammation and symptoms of this sensitivity from 1,000 to 10,000-fold. It is important to test both IgG and C3D at the same time to determine the culprit foods and the extent of the sensitivity. Food sensitivities are more subtle than an allergy and hard to determine with just an elimination diet, because it may take up to three or four days after consuming the food to have a reaction.

Food Allergy

A food allergy (IgE) is quite different than a food sensitivity. These are immediate responses to a substance or food that enters the body.  Food allergy reactions may be very serious and can cause symptoms such as difficulty breathing, hives or swelling. The antibodies produced by the body in response to the exposure can become confused, or cross reactive, and begin attacking foods. They are associated with allergies to food, environment, animals or even parasitic infections. Sometimes a person reports that they have “outgrown” their food allergy. The creation of an IgG4 (immunoglobulin G subtype 4) is associated with allergy therapies to help neutralize the reaction of IgE. Our bodies may also create IgG4 in response to exposure and IgE. Occasionally, very high levels of IgG4 may also be damaging and contribute to Eosinophilic Esophagitis, as well as autoimmune thyroid disease. IgG4 may also be a benefit by creating a blocking potential when IgG4 production is greater that IgE production. This will decrease the allergic reactions to the food allergy.


It is important to test for all these reactions when having a food allergy and sensitivity test to get the full picture. The Precision Point Diagnostics Precision Allergy 88 blood test will look at four groups of antibodies- IgE, IgG4, IgA and IgG, as well as complement C3D. Most other allergy/sensitivity tests only look at one group of antibodies. For individuals that have symptoms such as diarrhea, gas, bloating, fatigue, constipation, hives, or migraines, this is a test to consider.  After assessing an individual’s full history and symptoms, a plan can be developed to lower inflammation, heal gut permeability and blunt the immune response to restore health.

Dee Harris, RDN, is the owner of D-Signed Nutrition, located in the Bonita Bay Executive Center at 3531 Bonita Bay Blvd., Ste. 300, in Bonita Springs. For appointments and more information, call 239-676-5249 or visit