Are food intolerances real?

The answer to this question isn't always that straight forward. The most important point to remember is that food intolerances tend to be a digestion problem - not a food problem.

Are food intolerances real? Should you do an intolerance test?

Often, reactions are symptoms due to an inability to digest compounds found in the food, and the compounds involved can be numerous: fibre and fodmaps, fructose, oxalates, salicylates, lectins, or aggravation of gut inflammation. Or, the food in question may be causing a toxin load which you're having trouble excreting, which then instead causes skin eruptions or breakouts.

There are numerous reasons why you might have adverse effects to a type of food, which is why there is rarely much value in intolerance tests in my view, as these look only at one arm of the immune system. This doesn't tell us a huge amount about why a problem is occurring, and I usually therefore favour using client's resources on functional gut tests which goes straight to the root of any gut problem.

If you have intestinal permeability or 'leaky gut', you may have immune responses to a whole bunch of foods, but it’s not the fault of the food, it’s the fault of the gut lining. Saying that, effects can be powerful, and include significant joint inflammation and swelling, mouth ulcers, skin rash flairs, acne or bumps under skin, headaches, sinus problems, and even ear problems. Problems with the gut are even implicated in stubborn weight gain, depression, and female conditions such as PCOS or urinary infections.

How does one get intestinal permeability? Simply, the standard British diet which generally lacks fibre and/or is excessive in fat, can cause it. Obesity, alcohol, and stress are other factors - and how many people aren't experiencing stress and struggle with excessive weight in the UK

So how do you deal with it if you suspect you're 'reacting' to some foods?

A properly structured food elimination programme is the only properly effective way to establish food intolerances. However, I do have a cheat to this if food restrictions aren’t your thing. If you suspect a food causes you symptoms, have a three-day binge of that food (at your own risk) whilst diarising symptoms. The benefits are that you’ll have no trouble giving up any symptom-aggravating food after the trial if it has made you feel terrible, but the downsides are that you may, of course, feel truly awful if indeed a food doesn't create reactions.

To go back to my initial point that food intolerances are digestion problems and not food problems, it's important to focus on improving gut health. The aim is that you should be able to reintroduce problem foods in due course after you have done the relevant gut work. You will likely need to add in probiotics, prebiotics, fermented foods, and of course significantly improve your diet. A herbal antimicrobial course is often incredibly helpful also, but please consult a practitioner for more information on this, and never take antimicrobials for longer than a month or two as this depletes your gut flora.

You may initially not be able to tolerate fibre well, but this should never be excluded for any length of time as, again, your gut flora desperately needs fibre which it uses as fuel.

The views expressed in this article are those of the author. All articles published on Nutritionist Resource are reviewed by our editorial team.

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London W1H & NW6
Written by Linda Albinsson, Advanced Gut Health Nutrition Clinic
London W1H & NW6

Linda Albinsson is a highly experienced and qualified nutritionist specialising in areas of gut health, hormonal issues, cardiovascular disease and others

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