Hands up if you’ve ever eaten a meal only to find that, a period of time later, your body decides to object about it. Perhaps through painful bloating, wind, brain fog or that ‘something’s not right’ feeling that you can’t quite put your finger on. If so, you might have thought about taking a food intolerance test, to get to the root of the issue.
But are they worth it? Do they actually work? We’ll get to that, but, first off, let’s dig into what food intolerances actually are.
‘Food intolerances are far more common than food allergies and coeliac disease combined, affecting as many as 20% of adults,’ says Dr Megan Rossi, aka The Gut Health Doctor and author of Eat Yourself Healthy. ‘Although they’re not life-threatening, food intolerances can significantly impact your quality of life as well as your relationship with food – so it’s worth getting on top of them.’
But what exactly is a food intolerance? And how do you really know whether you’ve got one? And, if you do have one, can it be cured?
What is a food intolerance?
Quite simply, a food intolerance is a difficulty in digesting certain foods. How many people are affected is hard to tell but, one thing that is for sure, is that the number of people complaining of food intolerance symptoms (see below) is on the up.
‘The route of food intolerance is the quality of your gut,’ says Dr Gill Hart, biochemist and scientific director at York Test Laboratories.
‘The gut is a very sensitive – but key – organ. It contains 70% of your immune system, the role of which is to protect you. So, when you think about everything you’re bombarding your gut with nowadays, including environmental pollution, antibiotics – and, of course, the food you eat, much of which contains additives and chemicals – it’s not surprising that an increasing number of people are experiencing problems.’
What are the main symptoms of a food intolerance?
- Stomach pain
- Skin rashes or itching
- Joint pain
If left untreated, food intolerance symptoms can develop into something much more – think chronic inflammation and life-changing conditions such as Hashimoto, IBS, joint pain, unexplained weight gain or weight loss, fibromyalgia, skin problems and MS.
3 Common Food Intolerances
The big three, according to Allergy UK.
1/ Histamine intolerance
Biogenic Amines (aka histamine, tyramine and phenyl ethylamine) are chemicals that naturally occur in food – particularly wine and cheese. Although most people can tolerate these chemicals, if your digestive system is unable to break them down, it can trigger symptoms such as headaches, rashes, stuffy noses or nausea.
2/ Lactose intolerance
This refers to an inability to digest lactose (milk sugar) because of low levels of the enzyme lactase. Symptoms can include bloating, diarrhoea, wind and abdominal pain or discomfort. It is important to note that lactose intolerance is not an allergy, so it is different to a milk allergy.
3/ Gluten intolerance
Altered bowel habits, bloating, nausea, abdominal pain, a foggy mind, joint pains, fatigue, depression and a general lack of wellbeing can be a sign of a sensitivity to gluten. However, this type of intolerance is relatively new to be recognised so there is still a bit of debate as to whether it is caused by gluten or another protein found in wheat.
What’s the Difference Between a Food Intolerance and a Food Allergy?
If you suspect you have a food allergy, head to your GP and fill them in your symptoms.
- Rare – according to Dr Hart, they affect around 2% of the population
- Severe – antibodies develop immediately following contact with the allergen and can be potentially life-threatening
- Tends to be limited to one or two foods per person – such as fish, eggs, nuts and cow’s milk
- Symptoms develop gradually – perhaps following a couple of hours or even days
- On average, a few foods will cause problems – Dr Hart says four to five is a common magic number
- Anything with a protein can be a trigger
Are food intolerance testing kits worth it?
Of course, rather than buying any sort of kit, you could go to your GP, fill them in on your symptoms and ask if you can be referred for testing. (If you are experiencing symptoms that do not go away after two-three weeks, this is advised, regardless.)
With regards to the efficacy of at-home kits? Depends who you ask.
‘Despite the convincing marketing claims, there is no valid test for food intolerance (lactose is an exception), says Dr Rossi.
‘Take for instance, the IgG tests. This test involves exposing a sample of your blood to different foods and measuring the resulting antibody (IgG). However, most of us will develop IgG antibodies to food during our lifetime, despite not getting symptoms. This is because IgG is an indicator of repeated exposure, not a food intolerance.’
Dr Hart believes that IgG reaction tests are the best out there, when it comes to home kits.
‘You’ll come across many different types of food intolerance tests online,’ she says. ‘Blood tests, hair analysis, vega tests. But the most reliable are those that look for food-specific IgG reactions (inflammations) in your blood.
Watch out for those that use whole blood samples to see how the cells ‘react’ when foods are added to them – the reactions won’t be the same as when the foods are digested within the body; and, when it comes to hair analysis – well, from a bio-chemical view, it’s impossibly scientifically to test food intolerances in hair so there’s no way it can tell you if you’d had a reaction to food from these.’
‘There is no regulation of food intolerance testing, so many of those available to buy online, have no science behind them,’ she adds.
‘Look for a CE marked test that meets the requirements of European Directives, an accredited laboratory that is independently audited and published clinical trials to show that results are effective.’
The 3R Method
Dr Rossi’s recommendation, for discovering if you have a food intolerance? Turn detective and try to figure out what’s triggering your symptoms, yourself, using her 3R Method.
Step 1. Record
Keep a detailed food diary for seven days, or two weeks, if symptoms are less frequent. Try to keep your diet and lifestyle as normal as you can – the purpose of this stage is to identify whether anything you normally eat or do is causing the problem.
Be specific, including condiments like sauces and spreads, and how it was cooked; plus, the duration and severity of symptoms. Log entries in real time for best results – try a smartphone tracker app so you’ve always got your diary with you.
Step 2. Restrict
This stage takes planning. Avoid restricting a food during busy times to make it easier to stick to the restriction. Ensure you know the best alternative foods to include in your diet to ensure it remains nutritionally adequate.
Note: If you have multiple suspected culprits, seek advice from a dietitian before commencing this stage, to avoid the risk of nutritional deficiencies. Plus, if you think you might be intolerant to gluten or wheat, consult your GP to be tested for coeliac disease before excluding it from your diet.
Step 3. Reintroduce
This step is essential to confirm whether the suspect food component really is the cause of your gut symptoms and not just an innocent bystander. It will also help you determine your tolerance threshold.
On day one, start with one third of your normal portion, and increase by one third each day, as appropriate. If you do get symptoms, wait until you are symptom free again before moving on to the other test food.
‘I recommend cutting out the food in question for three to six months, then reintroducing trigger foods gradually,’ says Dr Hart. ‘You might be able to tolerate them again; you might not. It’s about getting to know your own personal cut-off points of how much of a particular food your body can manage.’
Do Food Intolerances Ever Go Away?
According to Dr Rossi, possibly.
‘Your food intolerance might not be forever,’ she says. ‘So, reassessing your tolerances over time is a good idea. If you find that you can tolerate small amounts of the food, then it is advisable to continue to include the foods up to your tolerance threshold.
‘If you do feel it is necessary to exclude them completely, remember to nourish your body with the other sources of the key nutrients to ensure your diet remains balanced.’
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