FOOD Intolerance - Could it be making you fat?


Sarah Merson, Natural Health Specialist

Year of publication: 

You eat healthily and get plenty of exercise, but still can’t seem to shift those extra pounds. Forget counting calories – your favourite food could be to blame. Sarah Merson reports.

Do you often feel bloated or suffer from fluid retention? Are you careful about what you eat, but still seem to find it hard to lose weight? Have you tried all the diets you’ve ever heard of and gone to every fitness class at the gym, but still find you’re the same size? If this sounds like you, don’t despair – it may be a food intolerance that’s stopping you shifting those excess pounds.

Statistics from Allergy UK, a national charity established in 1991 to increase awareness of food sensitivity, show that around 45 per cent of the UK population suffer from a food intolerance at some time in their lives. In fact, food intolerance is fast becoming one of the most likely reasons for ill health today. But how does it affect our weight?

What is food intolerance?

Food intolerance is often confused with food allergy but, in fact, they are quite different. “With allergies, symptoms can be very dangerous and even life-threatening. A food intolerance, on the other hand, is more likely to present itself with symptoms such as irritable bowel syndrome (IBS), eczema, migraine, fatigue, hives and asthma,” says Muriel Simmons, Chief Executive of Allergy UK.

Furthermore, they both activate different types of antibodies, which have different roles in the immune system. “An allergy generates the IgE immune response, which occurs when an antibody mistakes the food as a harmful alien, perhaps believing it to be a virus or bacteria, and attacks it. These responses are usually genetic, often appear in childhood and are unlikely to change. A food intolerance generates the IgG immune response, which is due to the presence of certain trigger foods,” says Simmons. The IgG antibody is responsible for the less severe symptoms associated with a food intolerance and, unlike an allergy, symptoms may take from an hour to several days to appear.

Poor metabolism

Ongoing research suggests that how well our metabolism functions is a key factor in weight loss or gain, and some of the foods that are most likely to trigger an intolerance are known to disrupt our metabolism. Research also shows that our metabolism works most efficiently when we eat a variety of nutrients. For example, a lot of processed foods contain wheat, which is one of the main food intolerance offenders, aren’t particularly nutritious and so slow down both metabolism and weight loss.

Craving the culprits

It’s common to crave the foods that we are intolerant to. According to Dr Jonathan Brostoff, a London-based allergy and environmental health expert, an estimated 50 per cent of people with a food intolerance crave the very food their bodies can’t handle. If we don’t get our regular fix, then withdrawal symptoms may kick in, often resulting in binge eating and weight gain.

Bloating & fluid retention

In the case of fluid retention, an offending food appears to affect the body by increasing the permeability of the capillaries (fine blood vessels), which means that extra water flows into the cells. Also, abdominal bloating might be a symptom of fluid retention, or it could be a sign that the digestive system is not dealing particularly well with a specific food, say Antoinette Savill and Dr Dawn Hamilton in their book Lose Wheat, Lose Weight (Thorsons, £7.99). Either way, excess weight is the result.

Chemical attack

The quality of food today also plays a part. Mass food production has meant that our diet has become highly processed and contaminated with chemicals and, in the case of wheat, bears little resemblance to what our great-grandmothers used when baking their daily loaf.

“We’re generally eating more processed foods, exotic foods and refined sugars and additives,” says naturopath Hermann Keppler. “We’re also subject to new ways of packaging and preserving food. In our busy, stressful lives, we often eat too much of a limited number of foods and also suffer from impaired digestion and elimination.”

All of these factors lead to our inability to digest food properly and result in a blocked digestive system. “It’s as congested as the M25 first thing on a Monday morning – clogged up with sugary, starchy foods and lacking the capacity to process them,” says Liz Tucker, author of Good Health Guide and Understanding Food Intolerance (PIC, £6.99).

Low energy

“The effort involved in processing a food the body is intolerant of puts a strain on the system because it has the addition of an inappropriate immune response to deal with,” says Tucker. This can cause low energy levels and can lead to a person becoming less active, which can result in weight gain. Once the intolerant food is removed from the diet, energy levels often increase and calories are burnt more efficiently.

How do you know if you have a food intolerance?

Ask yourself how often you eat the main offenders such as wheat and dairy. Chances are it’s surprisingly regularly. If you had cereal or toast for breakfast, a sandwich for lunch, a couple of biscuits mid-afternoon and pasta for dinner, some of the major culprits are included in each of your daily meals, and so your excess weight could be down to a food intolerance.

“When it comes to weight and diets, we seem to view our body as some kind of traitor, which can only be brought under control through means of deprivation, calorie counting and monumental willpower,” say Savill and Dr Hamilton. “Tracking weight issues and looking at possible food intolerance is working in harmony with, rather than battling against, your body.” If you think you may have a food intolerance, there are several avenues that you can take to confirm your suspicions:

DIY elimination diet

You could try to unveil suspected culprit foods by avoiding them for two weeks, and then reintroducing them in a controlled fashion, one by one, on different days, to discover which ones are causing the reaction. Keep a note of symptoms when you avoid certain foods, and which symptoms reappear when these foods are reintroduced. This requires motivation and discipline but can be highly effective. You may find it useful to keep a food diary.

Blood testing

This approach tests the antibody responses in the blood. Antibodies are defence proteins made by immune cells against alien substances in the blood, including unmodified food particles. YorkTest Laboratories has developed the FoodScan Intolerance Test and you can choose between either a FoodScan IgG 42 food test (costs £135 and tests for 42 different foods) or a FoodScan 113 food test (costs £260 and tests for 113 different foods). These tests analyse a tiny sample of blood from a pin-prick which can be carried out at home. This is then sent in to YorkTest and the results will be available in 10 working days. A Yes/No test called a FoodScan Food Intolerance Indicator Test (£19.99) is also available, which indicates whether you have a food intolerance or not, but is not food specific. For further information about these tests call YorkTest on 01904 410 410 or go to

Bio-energetic stress testing

This can be carried out by an experienced practitioner using a variety of different testing machines. Possible food intolerances can be tested by taking readings from various acupuncture points of very low electrical vibrations in the body. To find a practitioner in your area call the British Association for Applied Nutrition and Nutritional Therapy on 0870 606 1284.

People who experience gastro-intestinal symptoms from eating trigger foods very often report weight loss once the culprits have been eliminated.Kinesiology

Kinesiology can be defined as the use of muscle testing to identify imbalances in the body. It is a system of natural health care which combines muscle monitoring with the principles of Chinese medicine. It can also show how bodily imbalances are linked, put them in order of priority and determine the most effective treatment for you. For further information call the Kinesiology Federation on 08700 113 545 or visit

Foods most likely to cause an intolerance

Although any food can cause an intolerance, the most common offenders are milk, wheat, eggs, yeast and nuts. According to Cambridge Nutritional Sciences, who carry out specific tests for food intolerance, 40 per cent of their clients test positive to dairy. As far as wheat is concerned it appears to account for about 25 per cent of all food intolerances.

Symptoms of food intolerance can fall into several categories:

  • gastro-intestinal IBS and diarrhoea
  • dermatological
  • eczema and other skin related conditions
  • respiratory
  • asthma and wheezing
  • neurological
  • headaches and migraine
  • mental depression

At YorkTest clients are tracked several months after eliminating food intolerances with the help of a follow-up questionnaire. Dr Sarah Brewer, Medical Director at YorkTest, says: “People who experience gastro-intestinal symptoms from eating trigger foods very often report weight loss once the culprits have been eliminated. This is likely to be due to a reduction in bloating and fluid retention. However, as an ethical company, we do not make any weight loss claims.”

How do you deal with a food intolerance?

Once diagnosed with an intolerance, it may be necessary to avoid those trigger foods for a period of time. Your body may just have developed a temporary intolerance. After six to eight weeks, you might be able to slowly reintroduce the trigger foods. After all, foods like wheat and dairy, for example, can be part of a healthy diet and you should be able to retrain your body to accept them in moderation.

It’s highly likely that your immune system is a key player in the emergence of symptoms, so one of the best things you can do is support it, rather than undermine it. There are many natural ways to do this and it’s best to consult a nutritional therapist for guidance.

“It’s worth bearing in mind that stimulants compromise the immune system and by reducing them, you may find that you’re able to tolerate foods to which you were previously sensitive,” says nutritional therapist Suzannah Olivier, author of Allergy Solutions (Simon and Schuster, £6.99). Stimulants to try to reduce include caffeine, alcohol and cigarettes.

Or you could also try enzyme potentiate desensitisation (EPD). Similar in principle to homoeopathy, EPD works with the idea of treating like with like. Minute doses of the offending food are given together with an enzyme called beta glucuronidase, which works in the body to modify the effects of intolerance. For further information contact The British Society for Allergy, Environmental & Nutritional Medicine on 01547 550 378.

What if you don’t have a food intolerance, but still can’t lose weight?

A food intolerance isn’t the only reason why those pounds just won’t disappear. Perhaps your body is full of toxic deposits that are hindering the digestive process. In this case, a naturopathic detoxification diet might be beneficial. Maybe you have an underactive thyroid, which is a common cause of weight gain. If you think this might be the reason then discuss it with your GP. Or it could even be that you are holding on to excess weight for emotional reasons, in which case you might consider seeing a counsellor.

Sarah Merson specialises in natural health and has a diploma in nutrition. She is a regular contributor to a number of national magazines and newspapers. This article was first published in Spirit & Destiny.






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