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Can my symptoms actually be a food intolerance?

Photo by Cathryn Lavery on Unsplash

Food intolerances or "sensitivities" can affect you in so many ways.

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

I'm not talking about anaphylaxis or immediate allergic reactions that involve an immune response. Those can be serious and life-threatening. If you have any allergies, you need to steer clear of any traces of foods you are allergic to, and speak with your doctor or pharmacist about emergency medication, if necessary.

What I'm talking about is an intolerance, meaning you do not tolerate a specific food very well and it causes immediate or chronic symptoms anywhere in the body.

Symptoms can take hours or even days to show themselves. And symptoms can be located just about anywhere in the body.

This is what makes them so tricky to identify.

Consequences of food intolerances

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

  • Acne or rosacea

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

  • Shortness of breath

If your body has trouble digesting specific foods, it can affect your hormones, disrupt your metabolism, lead to adrenal fatigue, create a leaky gut, and/or even cause inflammation and result in any of the symptoms listed above. And these can affect any (or all) parts of the body, not just your gastrointestinal system.

How to prevent food intolerances

The main thing you can do is to figure out which foods or drinks you may be reacting to and stop ingesting them. I know that it sounds so simple, and yet it can be SO HARD to do!

The best way to identify your food/drink triggers is to eliminate them. You need to get rid of those offending foods/drinks. All traces of them, for three 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 if you want to slowly introduce them back one at a time while still looking out to see if/when symptoms return.

Two common food intolerances

Here are two of the most common triggers of food intolerances:

  • Lactose (in dairy - eliminate altogether, or look for a "lactose-free" label - try nut or coconut milk instead).

  • Gluten (in wheat, rye, and other common grains - look for a "gluten-free" label - try gluten-free grains like rice, quinoa or gluten-free oats).

Lactose is a sugar composed of galactose and glucose found in mammal’s milk and use to make many dairy products: cream, butter, milk, casein, cheese, whey, yogurt, milk powders, ice cream, etc.

Gluten is the name given to the protein found in some, but not all, grains:

  • Grains containing gluten – wheat (including wheat varieties like spelt, kamut, farro and durum, plus products like bulgur and semolina), barley, rye, triticale.

  • Gluten free grains – corn, millet, rice, sorghum, oats.

  • Gluten free pseudo-cereals – amaranth, buckwheat, quinoa.

So, if you can eliminate all traces of lactose and gluten for three weeks, it can confirm whether either or both of these, 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.

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.

If eliminating these two common food intolerances doesn’t work, then you can go one step further to eliminate all dairy (even lactose-free) and all grains (even gluten-free) for three weeks.

Keep a food journal

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. Click here to download a free copy of a Food Journal to help you track.

And, 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. 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, and sauces or dressings are notorious for adding ingredients that you'd never think are there. 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 you HAVE to ask the server in a restaurant about hidden ingredients, read labels, and consider cooking from scratch.

Food reintroduction

Once you have eliminated potential triggers for a period of at least 3 weeks, you may want to reintroduce a specific food in your diet to assess your tolerance.

For dairy, the reintroduction sequence should be butter, mature/aged cheeses, yogurt, soft cheeses, soured cream, heavy cream, milk, ice cream, whey powder.

For gluten, reintroduce rye, barley, wheat, one grain at the time. You may tolerate one, but not another; spelt is often well tolerated.

To do so, you will reintroduce one food, for example cheese, for 3 days in a row, then have a recalibration day, and move on to the next food you want to reintroduce, for example cow’s milk.

Why 3 days? Well, one exposure may not be enough to generate a response. So you need to add in one specific food for 3 days in a row, and only that food, and look for symptoms of intolerances.

What are the symptoms to look for? Here are some signs of a food intolerances:

digestive symptoms:

  • indigestion

  • altered bowel movements (diarrhea or constipation)

  • change in stools consistency

  • gas and flatulences

  • bloating

cognitive issues:

  • headaches

  • mental fogginess

  • difficulty concentrating

  • trouble remembering

  • mood swings

physical symptoms:

  • increased soreness

  • poor recovery from exercise

  • joint pain

  • lethargy

  • fatigue

skin reactions:

  • acne

  • hives

  • Itchiness

  • eczema

  • rosacea

respiratory symptoms:

  • sinus congestion

  • excess mucus

or anything different than your usual self.


Food intolerances are often difficult to figure out. The best tool to identify any is to do a strict elimination diet and keeping a thorough food journal. This exercise is more valuable than spending money on expense food sensitivities test that are often unreliable.

You may need to see a qualified healthcare practitioner for help and guidance. You do not want to continue suffering if you don't need to!



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