Food Allergies vs. Food Intolerances: Key Differences
A rapid and severe reaction to walnuts may indicate a food allergy, whereas bloating or congestion the day after eating ice cream often points to food intolerance. The term “allergy” refers to an IgE-mediated immune response, which can result in reactions as severe as anaphylaxis. In contrast, “intolerance” generally involves IgA- or IgG-mediated immune responses, which cause milder but still disruptive symptoms.
While both conditions are increasing in prevalence, food intolerances are less likely to be diagnosed due to their delayed onset and nonspecific symptoms. Common intolerance-triggering foods include gluten and dairy.
The Rising Prevalence of Gluten Intolerance
Scientific data show that over the past five decades, the incidence of celiac disease has increased from approximately 1 in 700 people to 1 in 100. This rise cannot be entirely explained by improved diagnostic techniques.
In individuals with gluten intolerance, consumption of gluten-containing foods—such as bread, cereal, snack bars, and processed foods—triggers an immune response that may cause a range of symptoms, including:
- Gastrointestinal discomfort and bloating
- Cognitive issues such as brain fog
- Neurological symptoms
- Hormonal imbalances, including thyroid dysfunction and fertility disruptions
- Fatigue, joint pain, and headaches
- Diarrhea, hypertension, and attention problems
Common Symptoms of Food Sensitivities
Symptoms linked to food sensitivities may include:
- Irritability
- Migraines and chronic headaches
- Gastrointestinal issues
- Fatigue
- Muscle or joint aches
- Diarrhea
- Elevated blood pressure
- Trouble focusing or cognitive difficulties
Addressing Food Intolerance: Identification and Recovery
Identifying and eliminating problematic foods is considered an essential step in managing food intolerance. Continued exposure to triggering foods can provoke immune responses that result in chronic inflammation and potential damage to various body systems. After removing intolerant foods from the diet, the immune system may stabilize, and inflammation may be reduced.
References
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