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The Difference Between Food Allergies, Food Intolerances, & Food Sensitivities

Updated: Aug 4, 2023

Though they may sound similar, many confuse these three conditions which can lead to inappropriate treatment and potentially worsen your symptoms.

Food sensitivities, Food intolerances
Food allergies

They are fundamentally distinct in the ways they affect the body, their symptoms, and how they are diagnosed and treated. This confusion can often lead to misdiagnosis and inappropriate dietary adjustments, impacting your overall health and your ability to reverse Hashimoto's. Through this article, I hope to breakdown these misconceptions and provide you with the knowledge necessary to understand and perhaps even identify these conditions in your own life or those of your loved ones.

Let's dive into these dietary reactions and shed light on their distinguishing features, so you can better manage your health.

Let's start with food allergies.

Picture this: You're at a summer barbecue, you take a bite of that juicy looking shrimp, and suddenly, your throat begins to itch & your lips start swelling. Before you know it, you're reaching for an antihistamine or even an EpiPen. That's a food allergy right there!

It's when your immune system suddenly overreacts to an otherwise harmless food protein - an allergen - and treats it like an invader. This causes a rapid allergic response that can be anything from hives and an itching mouth to more severe symptoms like difficulty breathing.

They are typically called IgE-mediated reactions and release inflammatory chemicals like histamine. Some people may develop a severe reaction called anaphylaxis which can be life threatening if not treated quickly. Symptoms of anaphylaxis includes swollen tongue, trouble breathing, trouble swallowing or speaking, tight chest, feeling dizzy, or collapsing. Most people usually carry an Epi-pen if they know they have a severe allergy in case of an anaphylactic reaction.

Symptoms: tingling or itchy of the mouth, hives, swelling of the face, mouth, or throat, difficulty swallowing, shortness of breath, feeling dizzy or light headed, nausea, vomiting, abdominal pain or diarrhea, or sneezing & itchy eyes, anxiety. Can be life-threatening.

Example: Peanut, Shellfish, Tree Nuts

Timing: Immediate reactions (few seconds to minutes)

Moving on to food intolerances.

You know that time when you had that extra scoop of ice cream, and later, your stomach had you urgently heading to the bathroom? That's most likely a case of food intolerance. Unlike allergies, food intolerances don't involve the immune system. They occur when your body can't properly digest or process a certain food. This is for life so you will react every time you eat these foods.

Lactose intolerance is a common example. People who are lactose intolerant lack the enzyme lactase, which breaks down lactose, a sugar found in milk. The undigested lactose ends up in the large intestine, and let's just say, it creates quite an impact.

Example: Lactose

Symptoms: Depends on the intolerance, but mostly gastrointestinal. The symptoms stay the same every time & the severity of the symptoms will increase based on the amount eaten.

Timing: Usually within hours of eating.

*The Carroll Food Intolerance Evaluation can help you figure out your food intolerances. This is only offered by naturopathic doctors & a service I provide for my patients.

Now, what about food sensitivities?

Food sensitivities are an abnormal immune reaction to food proteins that you normally wouldn't react to. It usually involves a breakdown of immune function and immune barriers. Testing for food sensitivities includes IgG, IgA, & IgM antibodies (food allergies involve IgE). Food sensitivities are closely linked to various autoimmune diseases and can trigger or flare up symptoms. For example, Hashimoto's is linked to gluten and dairy sensitivities.

Symptoms are usually less severe and can take longer (days) to appear, making them harder to pin down. If after eating certain foods, you feel a bit off, perhaps you get headaches or feel fatigued, you could be dealing with a food sensitivity. One way to help determine if you have a food sensitivity is to keep a food diary. Tracking your food and symptoms may reveal patterns that could link a specific food to your symptoms. Once you find these foods, then eliminate them for a period of time and see if symptoms improve. There are also food sensitivity tests, but be careful about choosing a test! Poor quality testing can lead to false negatives and positives.

Example: Gluten

Symptoms: Can affect multiple areas of your body not just the gut. Symptoms include but not limited to migraines, brain fog, stomach aches, acid reflux, bloating, joint pain, muscle pain, mood swings, fatigue, attention issues, short term memory loss, depression, hair loss, rashes, & high blood pressure

Timing of Symptoms: Delayed. May take hours to days for symptoms to appear.

I bet now you're thinking, "Great, but how do I know which one I have?"

Well, an important thing to note is that if you eat a food and it causes symptoms, then remove that food! No need any testing, you already know what is causing issues for you.

Now if you don't know or are having a hard time determining which food it could be (especially with food sensitivities), then that's where scheduling a visit comes in. I can guide you through tests and elimination diets to help pinpoint the cause of your food-related issues.

It's like a detective game, where each clue helps you understand more about your body and how it interacts with different foods. Understanding the distinctions between food allergies, intolerances, and sensitivities is the first step. From there, it's about tuning into your body, and with the help of a healthcare professional, developing a nutritional plan that serves your body best.

Disclaimer: The information provided in this blog is for educational purposes only and not a substitute for professional medical advice. Always consult with your healthcare provider for personalized guidance on managing Hashimoto's disease.

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