Why Most Food Sensitivities Start in Your Gut (and What to Do About It)

By Dr Kirsten Poe, PhD – Advisory Board, Allergy Test 
Meet Dr Poe: https://www.allergytest.co/pages/advisory-board/dr-kristen-poe

We hear a lot about food allergies and sensitivities these days, but it’s crucial to understand, they’re not the same thing. We need to clearly distinguish the big difference between an allergy and a sensitivity, because they impact the body in very different ways. Once we’ve clarified the differences, we can focus on the real game-changer: the gut. When it comes to food sensitivities, your gut health-especially your microbiome, digestion, and pH balance-is often the root cause of the issue.

Allergies vs. Sensitivities (Intolerances)

A food allergy is an immune system reaction that happens quickly, usually within minutes. Even a tiny amount of the food can trigger a strong response, like hives, swelling, difficulty breathing, or even anaphylaxis (a medical emergency). This is your immune system treating the food as a threat. Food sensitivities are slower and less obvious. They’re usually related to digestion, gut health, or inflammation, and do not trigger an immediate immune response. Symptoms might show up hours or even days later and can include bloating, brain fog, joint pain, fatigue, skin issues, or mood changes.

In a nutshell (no pun intended) Allergies = immediate, immune system, life-threatening.Sensitivities = delayed, digestive/inflammatory, uncomfortable but not dangerous or life threatening.

So, if you’ve ever felt bloated, gassy, or just “off” after eating certain foods. Even foods you used to tolerate just fine, it’s likely you have a food sensitivity and you’re not alone. Food sensitivities are more common than ever. But here’s the thing: most of them aren’t really about the food itself. They’re about what’s going on inside your gut.

Your Gut is the Gateway

Your digestive system isn’t just where food is broken down, it’s where your body decides what’s safe and what’s not. When your gut is working well, it breaks food down efficiently, keeps a healthy balance of bacteria, and acts like a secure filter for what gets into your bloodstream.

But when gut health is off, things can go sideways fast. Three big factors behind food sensitivities are pH imbalance, a disruption in your gut biome, and poor digestion/absorption.

1. pH Imbalance
   Your stomach needs to be acidic to break down food and kill harmful bacteria. If your pH is too low (not acidic enough), proteins and fats don’t digest properly. That undigested food can ferment or trigger inflammation, leading to discomfort and sensitivity.
2. Gut Microbiome Disruption
   Your gut is home to trillions of bacteria. When the balance shifts (from stress, antibiotics, sugar, or processed foods), the “bad” bacteria take over. This can lead to leaky gut, where the gut lining becomes permeable, and food particles sneak into the bloodstream - setting off immune responses and triggering sensitivities.
3. Poor Digestion
   If you’re not making enough stomach acid, digestive enzymes, or bile, your body struggles to break down food properly. This undigested food irritates the gut lining and feeds the wrong bacteria, making things worse over time.

So What Can You Do?

The good news is that you can heal your gut and reduce sensitivities with a few foundational steps:

First and foremost, get the right testing! Allergytest.co offers one of the most state of the art, easy, and inexpensive intolerance tests available! This panel screens for 1,400 sensitivity items including foods, food additives, nutrition, gut health and microbiome, metabolism and so much more. Results are delivered to you via one easy-to-understand report. The personal food intolerance report includes the following key elements:

– Explanations of the testing process.
– Elimination diet recommendations.

The expert team of intolerance technicians and lab managers have over 20 years of combined experience in allergy & intolerance testing and work from their category 2, ISO9001 accredited allergy and intolerance testing laboratory.

In addition to testing, you can:

• Support digestion with bitters, enzymes, or apple cider vinegar (as guided by a practitioner).
• Feed your good bacteria with fiber-rich, whole foods and prebiotics.
• Avoid processed and inflammatory foods that throw your gut off balance.
• Repair the gut lining with nutrients like L-glutamine, collagen, and zinc.
• Reduce stress, which directly impacts your gut through the gut-brain connection.

Most food sensitivities are symptoms of a gut that needs support. When you bring your digestion, pH, and microbiome back into balance, your body becomes more resilient, and food becomes less of a battlefield.