Okay… So What Is the Difference Between ‘Food Sensitivity’ and ‘Food Allergy’?

If you’ve ever Googled ‘Why do I feel 5 months pregnant after eating?’ this one’s for you.

Here’s the truth, not all adverse food reactions are allergies, and not all reactions mean you need to cut the food out forever. But knowing what kind of reaction you’re having can make a huge difference in how you eat and support your body. This translates to how you feel, how you can how up in your everyday life and your long-term health.

Let’s break it down simply, clearly, and without any overwhelm.

Does everyone use the same language around adverse food reactions?

Short answer is no. And I believe that this is something that needs to change so that people can make informed choices that truly support their body.

Conflicting definitions for food sensitivities, intolerances, and allergies appear everywhere; across the internet, among general practitioners and specialists, and even complementary health practitioners. Much of this confusion comes from the fact that this is a complex and evolving field. Clearing up confusion is one of my objectives; follow my work and you’ll understand why this is!

The simplified definitions I share here won’t capture every nuance, but they provide clarity and a shared language so you can understand the distinctions in how I apply them in practice.

Why this matters

Food and nutrition play a huge role in developing, maintaining, and activating the immune system. Understanding how your diet affects your immune system can uncover opportunities to feel better and prevent long-term health issues. This is so important in a world where despite advances in healthcare, hygiene, and nutrition, autoimmune and metabolic disorders are on the rise. At the same time, more people are experiencing allergies, sensitivities, and digestive issues. A dysregulated gut and inflammation can now linked to the chronic illness in our communities today.

Food, Immunity and Your Gut

The food you eat interacts with your immune system via the gastrointestinal tract. In fact, a large part of your immune system sits just beneath the lining of your gut (right where food passes through). How you digest and absorb food can influence your entire body.

Everyone wants to know what they should eat, but there’s no one-size-fits-all answer. This is why working with a practitioner that understands this is so important.

What is food allergy

A food allergy happens when your immune system mistakenly sees a food protein (an allergen) as harmful. It produces IgE antibodies, and subsequent exposure can trigger immediate, sometimes severe reactions, including life-threatening anaphylaxis.

Think:

• Immediate reactions, often within minutes to an hour requiring immediate medical attention.

• Requires medical testing (skin prick or IgE blood tests)

• People with severe allergies may carry an EpiPen

• Emergency response is necessary

What is food sensitivity

Food sensitivities also involve the immune system, but the reaction is delayed. Instead of reacting right away, your body can take up to 48 hours to show symptoms. Like a food allergy, the immune system generates food specific antibodies but these are called IgG, these are detectable in blood. Repeat exposure to the trigger foods can cause bloating, fatigue, mood changes, or skin issues like eczema. While food sensitivities aren't as immediate or dangerous as allergies, they can still profoundly affect your overall health and well being.

Think:

• Non celiac gluten sensitivity

• Elimination diets targeting common culprits like gluten and dairy

• Wide range of symptoms difficult to pinpoint due to delayed reactions

Bloating

Fatigue

Mood changes

Skin issues like eczema

Food Intolerance

Food intolerance is different from allergies and sensitivities because they don’t involve the immune system. Instead, they are caused by your digestive system struggling to process certain foods or food additives. For example, lactose intolerance happens when your body doesn’t produce enough of the enzyme needed to break down lactose, a sugar found in dairy. Other examples include sensitivity to caffeine or additives in processed foods.

Think

• People who eat lactose free dairy, avoid caffeine and preservatives.

• Lactose intolerance (not enough enzyme to digest lactose).

• Sensitivity to caffeine or food additives

• Symptoms often include bloating, cramps, or digestive discomfort

Can we test for the difference

Yes, although the complexity warrants a full blog post which is coming soon. Testing is available, but the quality of test, interpretation and follow-up are key.

Why it’s important not to mix them up

Allergies and sensitivities may sound similar, but they need very different approaches.

• Allergies require lifelong avoidance and immediate medical awareness.

• Sensitivities, on the other hand, need a strategic, personalised plan to identifying trigger foods, calm inflammation, and supporting gut repair.

Left unaddressed, ongoing food sensitivities can contribute to gut imbalance (like dysbiosis and increased intestinal permeability, often called “leaky gut”). Over time, this can create low-grade, long-term inflammation in the body.

And chronic inflammation doesn’t stay quiet. It’s been linked to serious conditions such as:

• coronary artery disease

• metabolic syndrome

• diabetes

• certain cancers

• autoimmune conditions

• neurological disorders including multiple sclerosis, dementia, schizophrenia, and depression

This is why clarity matters. When you understand the type of reaction your body is having, you can choose the right steps to calm symptoms now and protect your long-term health.

Different reactions → different solutions. Understanding which one you’re dealing with is the first step toward

easing symptoms and helping your body feel more balanced.

Next Steps

If you’ve been living with confusing reactions, bloating, or feeling like your body is working against you, please know this: you’re not imagining it, and you’re not alone. There is a clearer path forward. With the right understanding and a personalised plan, your body can feel calmer, more predictable, and more resilient. If you’re ready for support that meets you where you’re at, I’d be honoured to help. You can book a consultation with me and we’ll navigate this together.

References

Ahn, K. (2018). The past, present, and future of the research on food allergy in Korean children. Allergy, Asthma & Respiratory Disease, 6(Suppl 1), p.S44. doi:https://doi.org/10.4168/aard.2018.6.s1.s44.

Corley, D.A. and Schuppan, D. (2015). Food, the Immune System, and the Gastrointestinal Tract. Gastroenterology, 148(6), pp.1083–1086. doi:https://doi.org/10.1053/j.gastro.2015.03.043.

Escalante, J., Artaiz, O., Diwakarla, S. and McQuade, R.M. (2024). Leaky gut in systemic inflammation: exploring the link between gastrointestinal disorders and age-related diseases. GeroScience. doi:https://doi.org/10.1007/s11357-024-01451-2.

Pahwa, H. and Sharan, K. (2022). Food and nutrition as modifiers of the immune system: A mechanistic overview. Trends in Food Science & Technology, 123, pp.393–403. doi:https://doi.org/10.1016/j.tifs.2022.03.017.