Food allergies, intolerances, and sensitivities: Now what?

Unraveling Food Reactions

Having dealt with a range of food allergies, intolerances, and sensitivities, I can relate to the confusion these terms often create. Even though I use these terms interchangeably, each one has distinct meanings and effects on the body. It’s critical to understand the differences for proper diagnosis and treatment, yet these terms often complicate the understanding for the general public. The bottom line? Certain foods and ingredients just don’t agree with our bodies. The consequences of consuming these foods and ingredients can range from life-threatening reactions to mild discomfort or complete disruption of our well-being.

My personal journey toward understanding these food reactions has spanned over seven years, with guidance from doctors. After decades (yes, decades!) of postponement, I finally had no choice but to prioritize my health. If you’re interested in learning more about my experience, I invite you to read this post.

In recent decades, adult-onset food allergies, intolerances, and sensitivities have been on the rise. Yet, I’ve encountered people who assert that it’s just a fad. This view is not only misleading but also dismissive of the real challenges many face. Even within my own circle of friends and family, more people are realizing that symptoms like a persistent cough or joint pain after consuming foods like spinach or gluten aren’t just coincidences.

If you’re grappling with unexplained symptoms that won’t seem to go away, keep reading. I’ll break down the differences between food allergies, intolerances, and sensitivities. You might even begin to uncover the foods that are making you feel unwell. My journey began with one simple goal: identify the foods causing my issues and find effective ways to manage them.

Food Allergy: An Immune Response

A food allergy occurs when the body’s immune system overreacts to a specific food or ingredient, mistakenly identifying it as a harmful substance. While symptoms often appear quickly, they can be delayed by up to a couple of hours, making it difficult to pinpoint the allergen. Food allergies are typically diagnosed through blood tests, skin prick tests, elimination diets, oral food challenges or genetic testing. Reactions can range from mild to severe, with the potential for anaphylaxis, a life-threatening allergic reaction that can occur within seconds or minutes of exposure to an allergen.

Symptoms of food allergy

Common Allergens

The most common food allergens in the United States include:

• Egg
• Fish
• Milk
• Peanut
• Sesame
• Shellfish
• Soy
• Tree Nuts
• Wheat

Food Intolerance: A Digestive Response

Unlike food allergies, which trigger an immune system reaction, food intolerances result from difficulties in digesting certain foods or ingredients. These issues arise when the body lacks specific enzymes or has trouble processing certain compounds.

Food intolerances can be identified through an elimination diets, breath tests, or genetic testing. Avoiding or managing intake, and in some cases using enzyme supplements, may help alleviate symptoms.

Symptoms of Food Intolerance

Symptoms usually appear within minutes or it can take 12 to 24 hours of consumption. Food intolerance could also be dose-dependent, meaning that smaller quantities of the problematic food may be tolerated. However, the severity of symptoms can vary widely among individuals.

• Digestive Issues: Bloating, diarrhea, nausea, stomach pain
• Neurological Symptoms: Headache, migraine, nervousness, tremor
• Respiratory Symptoms: Rapid breathing, asthma-like symptoms
• Circulatory Symptoms: Palpitations, sweating
• Skin and Sensory Reactions: Burning sensations, facial and chest tightness

Common Food Intolerances

■ Lactose Intolerance

Lactose intolerance occurs due to a deficiency of lactase, the enzyme needed to digest lactose, a sugar found in dairy products. Without enough lactase, lactose remains undigested in the gut, leading to symptoms such as bloating, gas, diarrhea, and abdominal discomfort after consuming lactose-containing foods.

Common Sources of Lactose:

• Milk (cow, goat, or sheep)
• Soft Cheeses (ricotta, cream cheese)
• Ice Cream
• Yogurt
• Butter (contains minimal lactose but may still cause symptoms in some individuals)
• Whey Protein Products (depending on processing, some may contain lactose)

■ Gluten Intolerance

Gluten intolerance, also known as non-celiac gluten sensitivity (NCGS), involves an adverse reaction to gluten, a protein found in wheat, barley, and rye. Unlike celiac disease, an autoimmune disorder that causes intestinal damage, gluten intolerance does not lead to intestinal injury but can cause similar symptoms such as bloating, fatigue, headaches, and digestive discomfort.

Common Sources of Gluten:

• Wheat (bread, pasta, cereals, baked goods)
• Barley (beer, malt vinegar)
• Rye (rye bread, rye crackers)
• Processed Foods (soups, sauces, salad dressings, and other products with hidden gluten)

■ Histamine Intolerance

Histamine intolerance occurs when the body has difficulty breaking down histamine due to reduced activity of the enzyme diamine oxidase (DAO). This can result in symptoms such as headaches, hives, nasal congestion, digestive issues, flushing, dizziness, and an irregular heartbeat.

Common High-Histamine Foods:

• Alcohol (wine, beer, champagne—red wine is particularly high)
• Aged Cheeses (parmesan, gouda, blue cheese)
• Certain Fish (tuna, mackerel, sardines)
• Cured Meats (salami, pepperoni, prosciutto)
• Egg Whites
• Fermented Foods (sauerkraut, kimchi, miso, soy sauce)
• Shellfish (shrimp, crab, lobster)
• Histamine Liberators (spinach, eggplant, strawberries, citrus fruits, tomatoes)
• Sulfite-Containing Foods (beer, cider, wine, some dried fruits)
• Vinegar & Pickled Products (balsamic vinegar, pickles)

Common food sensitivities

Common Food Sensitivities Include:

• Dairy: Milk, cheese, yogurt, butter, ice cream
• Eggs: Chicken eggs, duck eggs, egg whites, egg yolks
• Food Additives
  • MSG: Often found in processed foods, soups, canned vegetables, and Asian cuisine
  • Sulfites: Found in dried fruits, wine, and some processed meats
• Gluten: Wheat, barley, rye, oats (unless labeled gluten-free), baked goods, pasta, cereals
• Nuts: Almonds, peanuts, walnuts, cashews, pistachios
• Soy: Tofu, soy milk, edamame, tempeh, soy sauce

Other Food Sensitivities Include:

• Caffeine: Coffee, tea, soda, energy drinks, chocolate
• Salicylates: Apples, strawberries, tomatoes, spinach, honey, coffee, tea, herbs (e.g., mint, rosemary)
• Shellfish: Shrimp, crabs, lobster, squid, oysters, scallops, snails

Uncovering the Mystery

One of my good friends and I had a ritual: whenever we would meet up to catch up, we’d go for dinner at a restaurant where we could have seafood. It was our thing, a tradition that never failed to bring us joy. But, like all things in life, that too changed.

Out of nowhere, she had a serious allergic reaction to something she ate, but the problem was that she couldn’t pinpoint the cause. It happened again. And again. After several dinners of mystery reactions, she realized the culprit: her body was reacting to shrimp and lobster.

At first, she thought it was a shellfish allergy, which is a common issue. But no! It turns out, she could still eat mussels, scallops, crab, and clams without any problems. Her doctor eventually identified it as an iodine allergy, a rare condition triggered by the iodine contained in shrimp and lobster.

If you ever find yourself in a similar situation, experiencing symptoms that leave you puzzled and unsure of their origin, it’s a good idea to start keeping a food journal. Write down everything: what you ate, when you ate it, and how you felt afterward. It’s a small but powerful step that can help you, or your doctor, figure out what’s causing the reaction. Trust me, it’s worth the effort to pinpoint the triggers. What seems like an isolated incident could just be a clue to something more.

The Power of a Food Journal

Whether you’re working independently or with a doctor, identifying your triggers is key. At first, tracking everything can feel overwhelming, but a food journal is a practical way to record food-related symptoms.

To make it easier, I recommend taking a photo of everything you eat and drink. The photo will give you a visual record of what you consumed and a timestamp. At the end of the day, set aside time to sit down and write in your journal: include all the food and ingredients you ate (with as much detail as possible regarding the ingredients), the time of consumption, any reactions or symptoms that followed, and the time those symptoms appeared. Pay attention to physical sensations (check the lists in this post), as well as your mood, thought patterns, energy levels, stress, and other changes. Even if something feels irrelevant, jot it down.

Example of a Journal Entry for Lunch

The goal is to spot patterns. Don’t rely on memory—writing things down is essential. Once you’ve identified a trigger, you or your doctor will have a clearer path forward. If you prefer digital tools, feel free to track your meals and symptoms on your phone using an app.

• Food & Ingredients: Chicken sandwich with grilled chicken breast (marinated in olive oil, lemon juice, garlic powder, paprika, salt, and pepper), whole wheat bread, lettuce, tomato, avocado, mustard, and a slice of cheddar cheese.
• Time of Consumption: 1:00 PM
• Reactions/Symptoms: Felt slightly bloated within 30 minutes after eating, mild stomach discomfort.
• Time Symptoms Appeared: 1:30 PM

Be Patient with the Process

If you’re one of the lucky few who can quickly identify triggers, that’s great! But for the rest of us, the process can be long and, at times, frustrating. I’m not going to sugarcoat it—figuring it out takes time. But this isn’t meant to discourage you. It’s about setting realistic expectations and understanding that our bodies are complex systems. For me, I might be able to eat a certain food one day and react to it the next. Is it my menstrual cycle, stress from a deadline, or just too much food at once? Probably a combination of all those factors. That’s why I truly recommend keeping a food journal—a vital tool in understanding your body.

Elimination Diet: A Step Toward Clarity

In addition to prick tests, blood tests, and DNA testing, I’ve also done several elimination diets to identify my food allergies, intolerance and sensitivities. Whether you are working with a doctor or are on this journey by your own doing, I find that doing an elimination diet has been extremely helpful in identifying my triggers.

In my experience, elimination diets are invaluable in identifying food triggers, even when blood tests or skin prick tests yield negative results. The elimination and reintroduction phases provide clear evidence of which foods are problematic.

As they say, the proof is in the pudding. When you see firsthand that eating a certain food triggers symptoms, eliminating it makes them disappear, and reintroducing it brings them back, that’s incredibly valuable information.

I’ve done my elimination diets with the guidance of doctors, but if you’re going to do it on your own, I suggest using a program you can follow. If you’re going to do it, you might as well do it right. The Elimination Diet: Discover the Foods That Are Making You Sick and Tired—and Feel Better Fast by Tom Malterre and Alissa Segersten will guide you through the process, helping you remove and reintroduce foods to identify what you can and cannot eat. Similar to keeping a food sensitivity journal, it requires some effort, but it’s a worthwhile investment in your health.

Making Informed Decisions with Yuka

My sister introduced me to Yuka, and it’s been a game-changer for avoiding hidden additives. Yuka is a mobile app that scans barcodes on food and products to assess their health impact, revealing detailed information about ingredients and potential additives. It’s been an invaluable tool, helping me make smarter choices about what I put in and on my body.

In Conclusion

As someone who has personally navigated the challenges of food allergies, intolerances, and sensitivities, I know how overwhelming the journey could be. Whether you’re working with a doctor or choosing to explore your triggers on your own, an elimination diet can be a helpful way to identify what your body can tolerate and what should be avoided.

The process of identifying food-related issues takes time, patience, and sometimes the guidance of a healthcare professional for an accurate diagnosis and management plan.

To break it down:

• Allergies trigger an immediate immune response and can be life-threatening.
• Intolerances affect the digestive system and are not immune-related.
• Sensitivities involve delayed immune responses, with symptoms that vary.

In many cases, the best way to manage reactions is by avoiding triggers, limiting exposure, or using enzymes. For severe allergies, your doctor might recommend carrying an EpiPen for emergencies.

My hope is that sharing this information inspires you to take a leap of faith into this process. I know it could feel long and lonely at times, but the commitment is worth it. After having made these changes, I now feel healthier, clearer, and happier. However, even on the tough days, keep going—you’ll thank yourself later.

Sources

• https://www.health.harvard.edu/blog/food-allergy-intolerance-or-sensitivity-whats-the-difference-and-why-does-it-matter-2020013018736
• https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/sweat
• https://acaai.org/allergies/allergic-conditions/food
• https://www.allergy.org.au/hp/anaphylaxis/first-aid-for-anaphylaxis
• https://pubmed.ncbi.nlm.nih.gov/39203877
• https://www.mayoclinic.org/diseases-conditions/food-allergy/diagnosis-treatment/drc-20355101

Resources & Tools Recommendations

The Elimination Diet: Discover the Foods That Are Making You Sick and Tired–and Feel Better Fast

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Clever Fox Food Sensitivity Journal Large – Daily Intolerance & Symptom Log for IBS, Diabetic, Low Fodmap, Elimination Diet

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Small Appliances Recommendations

Certain small appliances can truly transform your food preparation experience, making it both easier and more enjoyable. Whether you’re a seasoned chef or just starting to explore cooking, these appliances are designed to save you time, enhance your meals, and simplify your kitchen tasks. Here are a few must-have small appliances that can assist with food prep and cooking:

Vitamix 5200 Blender, Professional-Grade, 64 oz Container, Self-Cleaning, Black

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Breville Sous Chef 12 Cup Food Processor, One Size, Silver

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Crock-Pot 7 Quart Oval Manual Slow Cooker, Stainless Steel (SCV700-S-BR), Versatile Cookware for Large Families or Entertaining

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Instant Pot Duo 7-in-1 Electric Pressure Cooker, Slow Cooker, Rice Cooker, Steamer, Sauté, Yogurt Maker, Warmer & Sterilizer

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Claudia

What began as a quest to ease my migraines and allergies has since transformed me into a more self-aware, compassionate person with a deep concern for others and the world around me.

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