• Vanessa Bond

Are my symptoms food sensitivities or food intolerances?

Updated: Dec 27, 2021

Food intolerances and sensitivities can affect you in so many ways.

And they’re a lot more common than most people think.

Food intolerances and sensitivities are different from anaphylaxis or immediate allergic reactions that involve an immune response. Those can be serious and life threatening. If you have diagnosed food allergies, you need to steer clear of these foods (or traces of), and speak with your doctor or pharmacist about emergency medication, if necessary.

In my case, hazelnuts. My mouth starts to immediately itch and swell.

An intolerance or sensitivity means you do not tolerate a specific food very well and the food causes immediate or chronic symptoms. They can come and go, depending on your overall health status.

What's the difference between a food sensitivity or food intolerance?

In a nutshell (no pun intended), an intolerance means you're missing the enzymes to break down the food ... lactose intolerance is a great example. You have inadequate lactase enzymes to break down the sugar found in milk products (the sugar is called lactose).

A food sensitivity means you're reacting to the protein found in a food and almost all foods have proteins.

When you are in good health with little physical or emotional stress in your life, you can process sensitivities and sometimes, even intolerances.

However, certain factors can tip the scale, making you more susceptible to reactions. These factors can include bacterial imbalances in your intestines, external toxins, stress, electromagnetic frequencies, pollution, inadequate dietary fiber and more.

Symptoms of food sensitivities or intolerances can take hours or up to four days to show themselves. And symptoms can be located just about anywhere in the body.

This is what makes them so tricky to identify.

Symptoms of food intolerances and food sensitivities

There are some common food intolerances that have immediate and terribly painful gastrointestinal symptoms, such as lactose intolerance or celiac disease. These can cause stomach pain, gas, bloating, and/or diarrhea. Symptoms can start immediately after eating lactose or gluten.

On the other hand, other more insidious symptoms may not be linked to foods in an obvious way.

Symptoms like:

  • Chronic muscle or joint pain

  • Sweating, or increased heart rate or blood pressure

  • Headaches or migraines

  • Exhaustion after a good night's sleep

  • Autoimmune conditions like Hashimoto's or rheumatoid arthritis

  • Rashes or eczema

  • Inability to concentrate or feeling like your brain is "foggy"

  • Shortness of breath

  • Constipation

  • Diarrhea or frequent bowel movements

If your body has trouble digesting specific foods, it can affect your hormones and metabolism, cause inflammation, and result in any of the symptoms listed above. These symptoms can affect any (or all) parts of the body, not just your gastrointestinal system.

How to identify food intolerances or food sensitivities

You have the power to figure out which foods or drinks may be causing a reaction.


Stop ingesting them. I know, I know...this sounds so simple, and yet it can be SO HARD.

The best way to identify your food/drink triggers is to eliminate them. Get rid of those offending foods/drinks for at least four full weeks and monitor your symptoms.

If things get better, then you need to decide whether it's worth it to stop ingesting them. Or you can slowly reintroduce them into your diet one at a time while monitoring the return of symptoms.

Start Here: Two common food intolerances or sensitivities

Here are two of the most common triggers.


  • Lactose is found in dairy. It is a form of sugar. Eliminate altogether, or look for a "lactose-free" label. You can substitute nut or coconut milk.

  • FUN FACT … as we age, our bodies naturally produce less of the lactase enzyme we need to digest lactose. This is why people may be fine with dairy most of their lives and suddenly, WHAM. Cheese, milk and yogurt suddenly cause problems.


  • Gluten is found in wheat, rye, kamut, spelt and some oats. Look for a "gluten-free" label. You can also try gluten-free grains like rice, quinoa & gluten-free oats.

This is by no means a complete list, but it's a good place to start because lactose intolerance is thought to affect up to 75% of people, while "non-celiac gluten sensitivity" can affect up to 13% of people.

I fall into both groups. I break out in eczema on my hands after eating dairy or gluten. I also experience joint pain, a swollen belly, diarrhea and heart palpitations. Yet, the doctors say I'm not allergic. Hmmmm ...

If you can eliminate all traces of lactose and gluten for four weeks, it can confirm whether either (or both) are a source of your symptoms.

Yes, dairy and grains are a part of many government recommended food guidelines, but you absolutely can get all of the nutrients you need if you focus on replacing them with nutrient-dense foods.

A reliable way to monitor how you feel after eating certain foods is to track it. After every meal or snack, write down the foods you ate, and any symptoms so you can more easily spot trends.

As mentioned earlier, symptoms may not start immediately following a meal. You may find, for example, that you wake up with a headache the morning after eating bananas. Intolerances or sensitivities can appear up to 4 days after consumed.

You might be surprised what links you can find if you track your food and symptoms well!

IMPORTANT NOTE: When you eliminate something, you need to make sure it's not hiding in other foods, or the whole point of eliminating it for a few weeks is lost. Restaurant food, packaged foods, sauces and dressings are notorious for adding ingredients you would never expect. You know that sugar hides in almost everything, but did you also know that wheat is often added to processed meats and soy sauce, and lactose can even be found in some medications or supplements?

When in doubt, ask the server in a restaurant about hidden ingredients, read labels, and consider cooking from scratch.

How do I reintroduce foods?

There is a specific process you need to follow.

After four weeks, re-introduce gluten. Eat a lot of it in one day. Have a love affair with wheat. Enjoy toast with egg or almond butter for breakfast, then a sandwich for lunch. At dinner, indulge in some pasta, perhaps have some crackers as a snack, and then, go back to your elimination diet and wait 72 hours while you observe symptoms.

You may experience immediate distress. Or, you may not see physical signs until day two or three. Write all symptoms down - mood, energy, digestion, bowel movements, aches/pains. They are all relevant. If you notice returning symptoms, you have found your culprit.

What if it doesn’t work?

If you continue to experience symptoms DURING your elimination experiment, you need to dig a little deeper.

Some people (especially those with an autoimmune condition like Hashimoto's, psoriasis, lupus, rheumatoid arthritis, fibromyalgia or celiac) are sensitive to lectins which are found in abundance in grains, legumes, nightshades and other.

You may have other underlying food sensitivities that aren't gluten or dairy. Perhaps you've noticed that eggs hurt your stomach every so often or strawberries cause a rash. Soy, eggs, corn, nuts, seeds, legumes, shellfish, bananas and strawberries are also common triggers for those with a compromised digestive system.

If you fall into either category, you may need to see a qualified healthcare practitioner to help prioritize, which is one of the ways that I help my clients following an elimination diet.

You shouldn't suffer if you don't need to! Identifying food sensitivities and intolerances can be incredibly helpful in your overall health program.

If stuck, you can also consider food sensitivity testing, which is something I also help my client with.

I recently worked with one client who was on a very clean-eating regime, but felt unusually tired, bloated and her stomach hurt. Perplexed, we did a food sensitivity test and it revealed a sensitivity to almonds, among a couple of other foods that were higher in lectins (found in grains and legumes). She had been consuming large amounts of almond milk daily in her smoothies and using a pea/rice blend as a protein powder. After making a few tweaks to her diet, her energy resumed and her body started to rebalance.

So whatever your situation, don't distress. You have the ability to identify intolerances on your own, and there are many great practitioners out there who can help you prioritize changes to meet your goals.