Food sensitivity testing is an essential tool in functional medicine, helping clinicians identify the foods that may be contributing to a patient's chronic symptoms.
Unlike food allergies, which provoke an immediate immune response (IgE-mediated), food sensitivities typically involve a delayed immune response and may involve one or more non-IgE immune chemicals, making them more difficult to detect but often just as impactful.
Bay scallops are small bivalve mollusks found in beds along coastal areas. Florida bay scallops have blue eyes and can swim backward to escape predators.
In culinary terms, bay scallops are smaller and are considered more tender and sweet than sea scallops. However, the proteins in shellfish can cause strong allergic reactions in some people.
A shellfish allergy is an immune system reaction to proteins in marine animals like shrimp, crabs, oysters, and scallops.
Symptoms can range from mild issues like hives and congestion to severe and life-threatening reactions such as anaphylaxis, which requires immediate treatment with epinephrine.
People with this allergy must avoid all shellfish and food products containing shellfish, as even trace amounts can trigger a reaction.
Food allergies and food sensitivities are different immune responses to food. Whether a person has a food allergy or food sensitivity, the proteins in a particular food are often (but not always) responsible for triggering the immune system's reaction.
Food allergies, typically IgE-mediated, cause immediate, sometimes severe reactions like anaphylaxis within minutes to hours of eating the food, often triggered by common allergens like nuts, seafood, or dairy.
On the other hand, food sensitivities are more common and involve delayed non-IgE-mediated immune reactions such as gastrointestinal discomfort or skin issues, usually occurring hours or days after consuming the food. They may involve an IgG-mediated immune response, and other immune-mediated chemicals may also be present.
While food allergies can cause life-threatening reactions like anaphylaxis and are often identified early, food sensitivities are not life-threatening and can be managed with dietary changes.
Both are triggered when the immune system mistakenly identifies food proteins as harmful. Still, food allergies involve an immediate IgE response, while food sensitivities are due to a delayed immune reaction.
Food sensitivity testing such as this panel identifies various immune reactions, helping clinicians pinpoint which foods may trigger symptoms.
This testing can be helpful when it’s important to differentiate food sensitivities from food allergies, as they require different management strategies. Unlike traditional allergy testing, which focuses on immediate responses, food sensitivity testing can reveal delayed, less obvious reactions.
Different companies offer different panels, which may assess various biomarkers. Increasingly, a combination of the following biomarkers are seen:
IgG, IgA, IgM, and IgE antibodies are the primary markers tested for food sensitivities. IgG is a commonly tested antibody in food sensitivity panels, reflecting a delayed, chronic immune response.
IgA and IgM are also assessed regarding mucosal immunity and initial immune responses.
IgE is typically tested in food allergy testing, but it can sometimes be part of food sensitivity panels if a clinician suspects allergic reactions in addition to sensitivities.
Complement Markers may also be tested in some panels, offering insights into inflammation and immune system activation.
Food sensitivity panels often test for common foods like dairy, gluten, soy, eggs, nuts, and shellfish. These foods are frequently implicated in immune reactions due to their protein structures, which can provoke an immune response in sensitive individuals.
However, many companies now offer testing for additional foods to help clinicians craft more personalized patient food plans. The specific foods tested will depend on the patient's history, symptoms, and dietary considerations.
Test results typically include a range of reactivity, from low to high. Low reactivity indicates minimal immune involvement and may not be clinically significant.
High reactivity suggests that the food is likely a trigger for symptoms. It’s essential to interpret these results in the context of the patient's clinical presentation.
Positive results are not definitive diagnoses but guide further clinical action, such as elimination diets or further testing.
Food sensitivity testing is most useful when patients present with chronic, unexplained symptoms that don’t fit into conventional diagnostic categories. Conditions like irritable bowel syndrome (IBS), autoimmune disorders, and other inflammatory conditions may be associated with food sensitivities.
Testing may be especially useful when symptom patterns or patient history suggest a dietary trigger but when traditional allergy testing has been negative.
Food sensitivities are often tied to gut health and inflammation. Leaky gut syndrome, where the intestinal lining becomes permeable, is frequently linked with food sensitivities. Identifying specific triggers can help reduce systemic inflammation and improve gut function.
While food sensitivity testing can be highly informative, there are limitations.
False positives and false negatives can occur, as these tests may detect immune reactions that are not clinically significant. Additionally, sensitivity testing is not a one-size-fits-all solution—other factors, such as gut microbiota and leaky gut, should also be considered when interpreting results.
Finally, food sensitivity testing remains a somewhat controversial area, with some mainstream practitioners questioning its validity.
As with any assessment or treatment, the potential benefits should be weighed against the risks for every patient.
Click here to compare testing options and order testing for food allergies and sensitivities.
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