Think you might have food intolerance? Here’s how to figure it out

These days, more people are being diagnosed with conditions like Celiac's than ever before. As awareness for the condition has risen, it's resulted in more diagnoses and treatment for those who previously were just suffering without knowing why. We never even used to know that people could have gluten intolerances, a finding that has changed many people's lives, too.

But when everyone around you seems to be following a special diet, it's easy to wonder if you fall into one of these categories yourself. We all know what it feels like to eat a big meal and have a total belly bomb after. Yet feeling like that every day is no way to live.

If you're experiencing symptoms of indigestion, nausea, insane gassiness, or just feel downright crummy after most meals, here's how to figure out if you have a food sensitivity or intolerance.

First, you need to figure out if you have a full-blown food allergy

A sensitivity might make you uncomfortable or cause indigestion, but an allergy can be life-threatening. Both can cause nausea, stomach pains, excessive gas, and fatigue, but hives, a swollen throat, and itching or tingling of the lips are all signs you're having an allergic reaction. If you think you may have an allergy, stay away from the problem food and visit an allergist to get tested ASAP.

If it’s not an allergy, it could either be a “sensitivity” or an “intolerance,” which seem similar but are two different things

Sensitivities are also sometimes referred to as delayed food allergies, because they are also mediated by immune responses. A sensitivity can affect any organ system in the body and can take from 45 minutes to several days for symptoms to become apparent. Since the physiological mechanisms are complex, and symptoms may be delayed, it's often difficult to pinpoint a sensitivity, leaving many undiagnosed.

An intolerance, on the other hand, causes similar symptoms but doesn't involve an immune response. In this case, when a food is ingested, it is not properly digested and begins to ferment inside the gut. The most common example is lactose intolerance, which causes symptoms like diarrhea and gas, thanks to the body's inability to properly digest lactose.

Though the reason a food gives you discomfort is different whether you're sensitive or intolerant, the solution is the same: Stop eating it.

If you think you have either a sensitivity or intolerance, start tracking everything you eat

To pinpoint what's causing your symptoms, start a food diary. Write down everything you eat, and when symptoms occur. Then, after a week or so, look for correlations that may suggest causation. This is going to take some detective work on your part, but being aware of what you're eating and how it affects you is key for pinpointing a sensitivity or intolerance.

Start a basic elimination diet by cutting out all of the foods that you think may be causing problems

Once you've identified the food or foods you think are causing your distress, stop eating them. Pick four or five basic foods that you know for certain aren't causing your symptoms, and make that your base diet for the next two weeks. Why two weeks? That's about how long your body needs to reset itself.

After two weeks, start to add each food back in, one at a time

Pick one food (maybe the one you've missed the most?) and start eating it again. Wait two or three days, and if your symptoms don't return, add the next food back in. Keep doing this until you find one that causes symptoms. If there’s a reaction, take it out. Once you find a reactive food, wait three days for the immune system to calm down before trying to add another food back in.

Pay particular attention to foods that you eat all the time

If you’re noticing symptoms often, it’s probably because you have a sensitivity to something that you eat regularly. But that doesn't mean you have to say goodbye to your favourite food forever. If you get rid of it all and get your immune system to calm down, you can often add some back and be fine. We suggest waiting about three months to do so, and when you start eating it again, do so less regularly than before to avoid overloading again.

Be careful when removing entire food groups

Trying to improve symptoms in the short term can create long-term deficiency symptoms if you don't pay attention. Cutting out some foods can impact your gut's microbiome, whereas others can create nutrient deficiencies. For example, you shouldn't just get rid of dairy and not replace it with other foods that will give you the protein, calcium, and vitamin D you're now missing. You need to make sure what you take out you can replace.

See a dietitian if you're still having problems

If your at-home elimination diet doesn't give you solid results, see a professional. A registered dietician can perform a more in-depth analysis to figure out what you're sensitive or intolerant to, so if your situation is more complicated, bringing in the big guns may ultimately be necessary to finally get some answers.