Allergies and Food Intolerance!
Substances in foods, house dust and pollen can cause anything from sniffles to migraine, and even sudden death. Allergies are becoming increasingly common, but they are still not fully understood.
Allergens, the substances that give rise to all allergies, are minute particles of matter, found in the environment or in food, which the body regards as alien and potentially harmful. It responds to their threat with an armoury of antibodies released into the bloodstream or tissues.
Individual reactions to these clashes vary in intensity — from sniffles and sneezes accompanying mild hay fever, to the potentially fatal reactions suffered by people who are allergic to peanuts. Similar symptoms and illnesses can be triggered by different allergens, so that hay fever may be sparked by pollen, dust, feathers or animal fur. Equally, the same allergen may cause entirely different reactions in different people. The issue is further clouded by the confusion between an allergy and an intolerance.
Allergy OR Intolerance?
Allergic reactions to food can affect almost any part of the body, causing eczema, asthma, urticaria (HIVES) and other health problems. Anyone allergic to peanuts may, for example, swiftly develop swelling of the tongue and throat or a severe ASTHMA attack. In the most acute cases, nibbling only a tiny piece of peanut or eating a biscuit which incorporates peanut oil may even be fatal. The victims of these extreme allergies, or anaphylaxes, have an abnormal extreme reaction to a particular antigen. This can usually be countered with immediate administration of adrenaline by injection. Avoiding the culprit food is the only way to prevent such reactions.
Where there is an adverse reaction to food, but tests for allergy are negative, the phrase food ‘intolerance’, rather than allergy, is used to describe the condition. Although the immune system may be involved, it is not a major factor in causing the symptoms of reactions to particular foods.
Food intolerance is a highly controversial subject. In many cases, the cause of an intolerance remains a mystery, although it is known that allergic antibodies are not responsible. In some instances, it is the result of an identifiable problem. For example, people with lactose intolerance lack the ability to produce an enzyme called lactase which is needed to digest milk properly; and people with sensitivity to gluten suffer from impaired nutrient absorption because gluten damages the lining of their small intestine.
How Many People Suffer?
Allergy-related illnesses seem to be increasing rapidly. Experts now estimate that around one in three children exhibits symptoms of asthma, eczema or hay fever — before they reach the age of eleven years.
About 10 per cent of adults suffer from eczema and a similar proportion from migraine, while as many as one in five get hay fever.
Many of these conditions can be triggered by reactions to food. In South Africa specialists think that anywhere between 0.5 and 6 per cent of the general population may display an intolerance to or be allergic to certain foods to some degree.
Allergies can strike at any age. As people grow older their susceptibility and response to certain allergens will often change — particularly where these stem from diet. Both children and adults may outgrow an allergy without any change in diet; on the other hand, where an allergen has been identified and eliminated from a diet, new allergies may surface — sometimes months, or even years later — and cause similar or new symptoms. If a particular allergy is suspected, it can often be diagnosed either by skin testing or by excluding suspect foods from the diet. Both methods are simple and reasonably accurate. However, when there are no clues at all, identifying an allergy can be totally frustrating—like looking for the proverbial needle in a haystack.
Hyperactive Histamines
The skin and mucous membranes, or linings of the mouth, nose, intestines and some other parts of the body are able to produce a chemical called histamine. One of its functions is to stimulate the production of gastric juices after a meal. It also enlarges the capillaries (tiny blood vessels) to increase the blood flow. When food allergens enter the body or come into contact with the skin, the body reacts by releasing large amounts of histamine and other chemicals. It is the ‘histamine explosion’ that creates most of the symptoms of the allergic reaction. These may include itchy watering eyes, sneezing, wheezing, the appearance of a rash and diarrhoea.
In mild instances, the tongue or mouth may tingle — after eating eggs, nuts, shellfish, citrus fruits or berries, for example. This type of allergy or reaction to food is called the oral allergy syndrome.
Symptoms - SWIFT OR SLOW
Allergens can produce reactions anywhere in the body — in the nose, lungs, skin and even brain. When an allergic reaction appears swiftly after eating a particular food, the cause is often obvious and likely to point to a true food allergy. However, in some cases of asthma, glue ear and chronic rhinitis (characterised by a constantly congested nose), the food allergen may take many hours, or even several days, to produce the symptoms. A person may eat a particular food daily without realising it is causing a mild allergy. Only after avoiding it for two to three weeks will all the symptoms it has caused clear up. If the culprit food is included in the diet once again, all the original problems will reappear.
Migraine Triggers
There are various foods that are commonly cited by MIGRAINE sufferers as triggers for their attacks. Cheese, chocolate, citrus and coffee — known as the Four Cs’ — are the classic culprits. Others are alcohol, in particular red wine, sherry and port; meat extracts and stock cubes; nitrates, in processed meats; and miscellaneous foods ranging from milk to pulses.
Excessive Tiredness
Drowsiness can sometimes be due to a food intolerance. While it is natural to feel sleepy after a meal — resting ensures an adequate blood supply to the intestine as opposed to the muscles — some people experience almost continual lethargy. In many instances, these people are found to be sensitive to grains — particularly wheat. The process of digesting wheat can have the effect of releasing chemicals in the brain, inducing excessive sleepiness.
Excluding wheat from the diets of such people can improve their general health and boost energy levels.
Why Milk Causes Problems
Nine out of ten of the world’s adults are deficient in lactase, an enzyme in the lining of the intestine that breaks down lactose, the sugar present in milk and most dairy products. The enzyme is present in appreciable quantities only while babies are breast-feeding, and usually disappears after weaning when milk is no longer a staple food — its absence leads to lactose intolerance which in turn may cause diarrhoea.
Infants Reactions
Food intolerance usually becomes apparent when babies are weaned from breast milk to formula, because one of the most common food intolerance’s is to cow’s milk. Milk and eggs are frequently the cause of childhood eczema (atopic eczema). Some infants will react very quickly, crying inconsolably, or exhibiting symptoms of colic, diarrhoea or eczema. In others the reaction to foodstuffs may be delayed for hours or by as much as a day. Symptoms are usually relieved once the foods are excluded.
Some breast-fed babies react to milk which contains very small amounts of the components from food that the mother has eaten, but such instances are rare. A protective immune protein present in breast milk helps the baby to adjust to new foods which might otherwise provoke an allergic reaction.
Elimination Diets
Most doctors now accept that food intolerance’s can sometimes be the root cause of chronic diseases, including arthritis, Crohn’s disease, IRRITABLE BOWEL SYNDROME and hyperactivity. Yet these are only a few of the conditions which are claimed to have responded to elimination diets. Such diets are based on a systematic method of discovering whether a particular food is causing symptoms simply by eliminating it from the diet and seeing what happens. It is a tedious approach and sometimes the results are not clear-cut, but it is the most reliable diagnostic procedure available.
Because a huge range of symptoms may respond to the removal of specific foods from the diet, patients who feel better after starting such a regime may be tempted to expand the range of foods they exclude. But unintentionally eliminating or upsetting the balance of necessary vitamins and minerals can be dangerous; it is wise to consult your doctor or a qualified nutritionist before eliminating any foods from the diet.
How DIET CAN HELP
One of the most common digestive disorders is IRRITABLE BOWEL SYNDROME with its many accompanying symptoms. These include wind, bloated abdomen and irregular bowel habits which may often alternate between diarrhoea and constipation. At least half of the people with this condition suffer from food intolerance, with wheat grain being the most common culprit. Many people have found that a change in their diet helps to relieve the symptoms. Half of all people who are known to suffer from gastrointestinal complaints are sensitive to wheat, according to reports in some medical journals. Careful attention to diet would relieve the symptoms of almost all these patients.
Three out of ten rheumatoid arthritis patients can also be helped to some extent by diet. People with chronic migraine can also respond well. The health of more than half the patients with Crohn’s disease can be improved by an elimination diet, while trials in various countries suggest that delinquent behaviour in children can be improved by changes in their diet. However, it is dangerous to stay on an elimination diet.
The Effects Of Drugs
Certain medication and drugs predispose some people to food intolerance. For example, teenagers may develop digestive disorders after long-term use of tetracycline antibiotics for acne; some people develop irritable bowel syndrome after treatment with antibiotics, and others experience allergic reactions after taking steroids or oral contraceptives. Several mechanisms can therefore produce the same symptoms, making diagnosis even more difficult.
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Case study Sharon, a 27-year-old, suffered from what she assumed were cold sores. Occasionally, her lips and tongue tingled when she was eating, and moments later would actually swell, becoming painful and tender to the touch. One summer, the problem became very severe, and Sharon’s doctor asked her about her diet. it emerged that her father had grown a bumper tomato crop, and that Sharon was eating several of them with almost every meal. By following the doctor’s advice to cut tomatoes from her diet, Sharon has now successfully cured herself. |
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Could A Craving Be A Clue? There is no accurate ‘hit list’ of the foods or conditions responsible for reactions classed as intolerance. Individual diets, the victim’s age and any illness generated by the intolerance all play a part. But a reasonably reliable rule of thumb is that the more a person craves a particular food, the more likely it is that he or she will have a sensitivity to that food. |
