Food intolerance.

What does it mean?

Food intolerance means any regularly occurring adverse reaction , not mediated by IgE, to a food causing symptoms in one or more body systems.

This form of food intolerance is less obvious than IgE allergy, as it manifests itself only 24-48 hours after eating the offending food, unlike IgE reactions, which can be immediate and sometimes dramatic. Symptoms can vary from tummy cramps or diarrhoea to vague muscle pains or headache (including migraine) and even weight gain.

For example, although ADHD in children has no proof of association with excess sugar, additives or caffeine, many parents will confirm the association. There is also emerging research indicating that eating wheat, which contains gluten, can cause certain individuals to become psychotic. Most of the research on schizophrenia is focused on neurotransmitters, and the usual treatment is neuroleptic medication which tends to have serious side effects. Some researchers have been looking at wheat as a cause of schizophrenia, as many schizophrenics seem to have a history of celiac disease (gluten/ wheat intolerance) as children which can be as much as 100 times that in the rest of the population. Meanwhile, populations who traditionally eat a gluten-free diet have extremely rare occurrence of schizophrenia -- just 2 in 65,000 versus 1 in 100 in grain-eating countries. In addition, when populations westernize their diets, schizophrenia becomes more common.

It should be noted that non celiac gluten sensitivity is now a recognised entity, and may manifest in many ways, including skin disorders, migraine, cluster headache and other neurological and behavioural  problems, as well as irritable bowel syndrome and obesity.

What it is not

Food intolerance is not the same as an allergy and is not life threatening. It does not include certain reactions to food such as bloating after eating pulses, which is a normal and common reaction.

Who gets it?

It is now realised that these food reactions are far more common than was originally thought, and in one study up to 20% people admitted to some kind of food intolerance; it is something that you will only find once you know to search!

People who have any undiagnosed aches and pains, fatigue, and those with a genuine problem with their weight may all benefit from a brief exclusion diet, as it appears that some people actually crave the foods to which they are most sensitive. This constant intake of an ‘irritating’ food leads to increased plasma cortisol levels with weight gain and general feelings of being ‘unwell’.

What are the causes:

The reactions may be due to toxic, idiosyncratic, pharmaceutical or metabolic factors, and may be in the gut respiratory system, skin or nervous system. They may be immune related via IgG as in celiac disease, where the sufferer has antibodies against wheat gliaden, or they may be due to an enzyme deficiency, as in lactose intolerance where the enzyme lactase, that breaks down lactose, is missing, causing an osmotic diarrhoea with abdominal cramping. Alternatively the reaction may be idiosyncratic , as with the foods that commonly cause migraine: cheese, caffeine, citrus and chocolate. In a 1979 study published in the Lancet, 60 migraine sufferers with food antigen immunoreactivity (i.e. positive IgG tests) who were put on an elimination diet experienced profound relief. According to the author:

"The commonest foods causing reactions were wheat (78 percent), orange (65 percent), eggs (45 percent), tea and coffee (40 percent each), chocolate and milk (37 percent) each), beef (35 percent), and corn, cane sugar, and yeast (33 percent each).

When an average of 10 common foods were avoided there was a dramatic fall in the number of headaches per month, 85 percent of patients becoming headache-free. The 25 percent of patients with hypertension became normotensive. Chemicals in the home environment can make this testing difficult for outpatients. Both immunological and non-immunological mechanisms may play a part in the pathogenesis of migraine caused by food intolerance."

A study published in 2010 also found that a six-week long diet restriction produced a significant reduction in migraines in those diagnosed with migraine without aura.

 How is it diagnosed?

IgG testing is popular in some areas, but there are as yet no studies to show the reliability of a positive result. Further research is needed in this field. Apart from tests for classic celiac disease (gluten), fructose and lactose intolerance, skin and blood tests are generally of little use, and diagnosis is by history and food challenge. ‘Alcat’ testing is generally regarded as unreliable and results do not reproduce on retesting the same individual.

A food diary is a useful tool, write down everything that you eat and drink for 2 weeks, and alongside note when your symptoms appear. remember the reaction may be delayed by as long as 24-48 hours.

A simple way of testing yourself is by taking your pulse before and after a suspect food, (this test will not be valid if you are taking drugs such as beta blockers etc that affect your heart rate). Choose a quiet and peaceful environment to conduct your test, away from stimulus from others, the radio or television.

First find a baseline for your normal healthy pulse rate. Take your pulse rate for a full minute, and do this at three different times to validate your readings. Take this either sitting down or lying down, but be certain to use the same position to conduct the test.

If possible test each food item alone rather than in something with many ingredients e.g. some white sugar rather than a donut. Take your pulse again while the food is in your mouth.

The test would be considered positive if your pulse increases by 10% or more. Borderline foods are between 7%-10% and can still affect you health, so need to be avoided. Any food that produces an increase in your pulse of 10% or more in a pulse test is considered to be sensitive and should be eliminated from your diet. The higher the increase in pulse rate the higher the sensitivity to the food.

Elimination diet with food challenge is the most useful test, but only if all suspect foods are completely eliminated. Such a diet is usually nutritionally inadequate and should not be followed for more than 10-14 days. Any suspect food, as well as any food eaten more than 4 times a week, should be eliminated, and it should be individualised as far as possible, although extreme cases can follow the full elimination diet. The suspect foods are then reintroduced 1 at a time. An example of such a diet can be found at:

Remember that you can also be sensitive to food additives like artificial colours, preservatives, flavour enhancers (MSG), and aspartame, so read food labels, and keep a note of the ingredients in a food journal, noting when symptoms appear in relation to food intake.

What is the usual treatment?

The only treatment is complete avoidance of the offending food, and often similar foods in the same family. This may only be necessary for a few months, after which the offending food can be carefully reintroduced. If symptoms recur, then remove it again for a further 3-6 months.

In the case of celiac disease, the disorder is lifelong. Researchers are seeking ways to enable sufferers to eat some gluten by introducing an edible enzyme that will break it down in the gut before it can be absorbed and do damage, but this is so far only in the research stage.

What other treatments are available?

If you eat something to which you react badly, you may find the tummy rescue smoothie recipe below, which was developed as a response to a "gluten emergency” helpful. The healing properties of each ingredient are also listed.  Purée in blender until smooth, and slightly thickened.  It is most soothing when consumed while still warm from the hot tea.

Tummy Rescue Smoothie:

1 cup hot freshly brewed nettle leaf tea (anti-histamine, anti-spasmodic)

¼ cup  pear juice (flavouring/sweetener - pears are the least allergenic of fruits)

¼ - ½ teaspoon whole fennel seed (reduces gas & bloating)

2 Tablespoons slippery elm powder (healing & soothing to mucous membranes and the gut)

1 Tablespoon flax seed oil (soothing, anti-inflammatory)

¼ - ½ cup rice milk (hypoallergenic, use to thin to desired consistency).

This smoothie is best consumed in small sips over an hour or so.  Magnesium also helps with pain and relaxes muscle spasms, so taking a little extra magnesium may be of benefit. For severe symptoms, drink the smoothie while reclining in bed, with a warm castor oil pack over the abdomen, covered by a heating pad set on low.  Do not leave the pack in place for more than an hour.

When to worry

Celiac disease has long term implications for those who continue to eat gluten, and the incidence of intestinal lymphoma is significantly increased in these people. They may also suffer nutritional deficiencies due to the poor ability of the gut to absorb nutrients. All these problems resolve on a fully gluten free diet.

Most food sensitivities have no long term complications, but the symptoms resulting from them, such as migraine, fibromyalgia etc, may lead to other problems such as overuse of medication.

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