What is the best type of food allergy test
There are also numerous commercially available tests that claim they can diagnose food hypersensitivity. These should be avoided as they own no scientific basis and can be harmful when multiple foods are excluded without reason and if they are not reintroduced under guidance of a dietitian.
The pulse is taken before eating the suspect food and then 15 minutes afterwards. An increase of ten beats per minute would indicate food intolerance. Research shows there is no connection between the increased pulse and food intolerance and is therefore not recommended.
IgG blood test
This blood test looks at IgG antibodies present in the blood. It’s claimed that an increase in IgG to a certain food indicates an intolerance to that food.
At present there is no convincing evidence to support this test, and it’s not recommended as a diagnostic tool.
This is based on the thought that certain foods cause an energy imbalance in the body which is detected by testing the response of the muscle. The client holds the suspect food which is in a glass vial and the therapist tests the muscle response. The result can lead to numerous foods being eliminated from the diet however research studies show that this test is no better than chance and is therfore not recommended.
A little lock of hair is sent off to a laboratory and the energy fields in the hair are scanned. The results are compared to other established data to identify a food hypersensitivity.
Although this is used in testing for recreational drug use as well as lead and mercury poisoning, its use in allergy testing is unproven and has no scientific basis.
Leucocytotoxic or Cytotoxic test
This is a blood test where the white blood cells are mixed with the suspect food and if they swell this would indicate a problem with that food. There is no rational scientific basis for this test.
Electrodermal (Vega) test
This test measures the electromagnetic conductivity in the body. An offending food will show a dip in the electromagnetic conductivity. Research studies show that this test is no better than chance.
These alternative allergy tests may propose endless lists of foods to be excluded from the diet unnecessarily.
Excluding a major food group e.g. wheat or milk, or a combination of diverse foods, creates numerous practical difficulties. Without excellent nutritional advice, a restricted diet can lead to severe nutritional deficiencies and malnutrition.
Food allergy — symptoms
A variety of symptoms may indicate the presence of an allergy or intolerance. Some are mild and barely noticeable, while some cannot be overlooked and others are even extremely severe, such as allergic shock.
Food allergies do not always just affect the mouth and the gastrointestinal tract, since they can also impact on the skin and the respiratory tract[2, 5].
In the extreme case: allergic shock
The most severe form of allergic reaction is allergic shock, which is also referred to as anaphylactic shock. The causes of this are generally insecticides, medicines and, especially in children, food. But foods such as nuts, soya, shellfish, milk and eggs can also cause anaphylaxis.
In anaphylactic shock, large amounts of histamine are released, resulting in severe dilation of the blood vessels.
The blood pressure falls rapidly, while dizziness, fainting and even death can happen in the worst case.
If you are aware of the risk of shock, you should reply quickly if more severe allergic symptoms happen and call the emergency services immediately. While waiting for the ambulance arrives, the victim should be placed in the shock position, i.e.
lying below with the legs up. At-risk patients also often carry an emergency kit containing an adrenaline pen.
This emergency medicine will ensure that the shock abates[3, 4].
And this is excellent to know: Depending on the severity of an allergy, even the smallest amounts of an allergen sometimes suffice to trigger an anaphylactic shock — such as the remains of a nut on the partner’s lips or traces of soy in certain foods[3, 4].
What are the symptoms of food allergies?
In allergic reactions, the following symptoms frequently occur:
- Breathlessness extending to allergic asthma
- Redness and wheals on the skin (nettle fever)
- Diarrhoea, vomiting and abdominal pain
- Burning in the oral cavity, swelling of the mucous membranes and tongue
- A drop in blood pressure
Just because you own an allergy, you will not automatically reply to the slightest sign of the allergen.
A reaction threshold exists, meaning that you need exposure to a certain quantity of the allergen before symptoms happen. As an example, peanut allergy sufferers often own a extremely low reaction threshold, with a little crumb of a peanut being enough to cause a furry tongue and swollen neck.
Stress, sports and infections can also lower your reaction threshold. This will make it more likely that you suffer an allergic reaction.
During or immediately after exercise, the risk of an allergic reaction is increased.
This phenomenon even has a name: namely exercise-induced anaphylaxis (EIA). If you eat a food that you are allergic to correct before exercise, you may experience hives and itching, or feel drowsy. You should avoid any of your food allergens at least four to five hours before each workout.
Studies own shown that stress can make the symptoms of allergy worse and more likely to happen. If you suffer from an allergy and are often stressed out, it makes sense to deliberately seek to be relaxed.
Relaxation techniques such as yoga, autogenic training and progressive muscular relaxation can every help.
Infections can also potentiate allergies. Elevated temperatures lead to increased blood circulation, which in turn can cause more allergen to enter the bloodstream. With infections in the gastrointestinal tract, allergies are aggravated by the fact that a larger quantity of undigested proteins crosses the mucous membrane. As a result, such proteins affect the sensitised immune system and are more likely to trigger an allergic reaction.
Alcohol is also discussed as an allergy-enhancing factor among scientists.
In some case studies, allergy symptoms were exacerbated under the influence of alcohol, and in alcoholics the number of IgE antibodies is increased. Conclusive scientific evidence for this association, however, does not yet exist.
If a food allergy is suspected, you should seek medical advice and discuss the use of evidence-based, conventional allergy testing. Alternative allergy testing should be avoided as it has no scientific basis.
Dietitians can give you the correct nutritional advice and ensure a well-balanced nutritional intake which will be tasty, varied and culturally acceptable.
Children should not follow a restricted diet unless supervised by a dietitian as they require a wellbalanced diet to ensure adequate growth and development.
How can you recognise and avoid incompatible foods
Anyone who has an allergy or intolerance towards a food needs to study ingredients lists and change their diet. The genuine challenge in numerous cases, however, is to discover out exactly what it is that you cannot tolerate. We can tell you how to do that.
Harvard scientists own recently evaluated 2.7 million files of American patients.
Their result: Around four percent of every people suffer from some helpful of food allergy. For Germany, similar numbers are available, and according to the German Nutrition Society, three to four percent of adults own an allergy towards food. Significantly more common are food intolerances such as lactose intolerance which affect 15 to 20 percent of every people.
Concerned individuals must carefully study ingredient lists to stop any nasty surprises after dinner that can range from stomach rumbling, severe flatulence, rashes and dizziness to anaphylactic shock. And it is not always simple to associate a specific foodstuff with the symptoms.
The consequence: people finish up not finding out what is lacking in them.
In this article you will study what happens when you own a food allergy in the body, what symptoms are indicative of an allergy, and how you can get back on track with a blood test and an elimination diet. Also: the types, symptoms and treatment of food intolerances.
What is a food allergy?
When you own an allergy, your immune system reacts strongly to an otherwise harmless substance.
The substances which can trigger allergies are known as allergens. These are diverse proteins may happen in pollen, animal hair, the faeces of dust mites or even in food.
What happens with an allergy in the body?
An allergy always starts with a sensitisation towards an allergen. This means that the body will produce certain IgE antibodies in an excessive quantity. Each of these immunoglobulins (the «»Ig»») specialises in keeping specific intruders out of the body. In doing so the immune system will combat bacteria, viruses, worms, but unfortunately also harmless allergens.
IgE antibodies bind to receptors on mast cells, which are cells of the immune system.
Laboratories can detect the increased number of IgE antibodies in the blood and assign these to their corresponding allergens – and this is how an allergy test by blood sampling works. If the allergen comes into contact again, the allergen will bind to the IgE antibodies and cause the mast cell to release messenger substances such as histamine. Histamine then promotes inflammation and in so doing triggers the diverse symptoms of an allergy. If in addition to sensitisation symptoms happen, we speak then of an allergy[3, 4].
What types of food allergies are there?
Experts distinguish between diverse types of allergy.
The most common forms of allergy are those of the immediate type, namely type I allergies, which also includes food allergies. The reaction occurs directly after you own consumed the allergen. A person allergic to peanuts then feels symptoms such as a furry tongue and rash between a few seconds and 20 minutes after eating. Delayed immediate reactions are also possible in which another allergic reaction can happen after four to six hours.
And this is excellent to know: some food allergies can resolve themselves by themselves during adulthood. For example, milk, egg, soy and wheat allergies generally affect children but then vanish in 90 percent of cases.
Allergies to nuts, fish and shellfish, however, are generally retained for entire lives.
How does a food allergy develop?
Allergies are today talked of as a disease of modern civilisation. The number of allergic diseases has increased over recent decades more and more. Scientists are not fairly certain why that is.
A favorite explanation is the hygiene hypothesis, which has put the blame for allergies on a modern lifestyle away from dirt and germs. Nevertheless, genetic factors also seem to frolic a role.
Does breast milk protect us from allergies?
For the immune system to develop healthily, it is ideal for mothers to breastfeed their infants for at least four months. Until just a few years ago, strict nutritional guidelines were recommended.
To reduce the risk of allergies, breastfeeding women had to avoid eggs, nuts, dairy products and wheat products. Experts also advised against touching baby porridge with their gluten-containing grains. And fish was just as much taboo, as sometimes were celery or carrots.
New studies own turned these recommendations on their head. They showed that children are more likely to tolerate foods if they own been in contact with them while still in the womb or breastfeeding. Of course, this only applies if the kid has not already developed an allergy!
And this is excellent to know: Since if your baby has a food allergy, you, as its mom, should also avoid that food during breastfeeding.
Are allergies inherited?
As a law, nobody is born with an allergy.
But humans can own an inherited predisposition towards developing an allergy. In other words, you can own a significantly higher risk of developing an allergy.
This often applies to allergies in general, i.e.: the children of parents with hay fever are susceptible to every allergies, whether it be against pollen, animal hair or food. This also applies to other so-called topical or contact diseases, which are closely related to allergies and which often happen together with them (such as with atopic dermatitis and asthma)[2, 8, 14].
And this is excellent to know: as an unborn baby, the womb is our home — and this influences how our body develops. As such, the mother’s diet can also influence the development of allergies. Birth by caesarean section and a high age of the mom also seem to increase the risk of developing a food allergy.
Does dirt protect us from allergies?
The hygiene hypothesis is based on the observation that allergies are particularly prevalent in cities and much less common among children raised on a farm.
The theory goes that in the hygienic environments we inhabit in the Western world, our immune system seldom encounters foreign bodies such as pathogens, worms, and parasites. The defences own little meaningful to do and only rarely use their powers to defend themselves against harmless substances such as food and pollen – and this is how an allergy arises[2, 7, 9].
And this is excellent to know: whether we develop an allergy over the course of our lives is decided during the first months of life, and perhaps even in the womb.
It therefore depends on the environment in which babies live at the beginning of their lives – and later holidays on the farm will not be capable to prevent any allergies.
What role do the intestines frolic in the development of allergies?
The microbiome (archaically known as the intestinal flora) describes the composition of the billions of bacteria that inhabit our gut. This microbiome plays a key role in helping our immune system develop from earliest childhood onwards. Researchers propose that our modern way of life affects intestinal bacteria, which in turn can own an impact on the development of allergies.
A study from Estonia showed that Estonian children, who still grow up relatively frequently on farms and spend a lot of time outdoors, own a much better bacterial colonisation of their intestines than children from Sweden, who are less likely to grow up on farms.
How to prevent an allergy
The appearance of an allergy is a complicated process that scientists still do not fully understand.
There are no binding recommendations for preventing allergies.
Medical guidelines, however, provide recommendations that make an allergy a little less likely. They are aimed at «»families at risk»», i.e. at families in whom allergic diseases, atopic dermatitis or asthma also happen. Recommendations also include:
- You should not hold a cat as a pet — unless the kid is at a high risk of developing a cat allergy.
In this case an early contact can actually own a positive effect.
- That the mom and kid should not refrain from allergens in the diet, since even the consumption of fish by the mom can exert a protective effect.
- From pregnancy, mothers should also avoid tobacco smoke.
- Pregnant, breastfeeding and children should not come into contact with mould.
- You should be exposed to as little vehicle exhaust as possible
Common food allergy terms
Medical terms for food allergy and intolerance can be confusing, so here is a list of their descriptions:
A specific IgE test, formally known as Radio Allergo Sorbent Test (RAST) is carried out by measuring the quantity of IgE antibodies to a suspect food in the blood.
The results are interpreted with a detailed clinical history to give a diagnosis of IgE mediated food allergy. This blood test can be organised by your GP or hospital clinician. There are commercial companies who offer a similar blood test called MAST (Multi-Allergen Screening Test). However, as they do not own your detailed clinical history, it is hard for commercial companies give an precise diagnosis.
Covers every bad reactions to food.
Non-IgE mediated food allergy
The reaction is delayed or ‘slow onset’. The immune system is involved but not IgE antibodies. Allergy testing is not helpful.
Conventional Allergy Testing
These tests are evidence-based and performed by registered health professionals:
Skin prick test
A little quantity of diluted allergen (suspected protein that person is allergic to) is placed on the skin and the skin is then pricked.
If a little swollen lump or ‘weal’ appears, in conjunction with a detailed clinical history, an IgE mediated food allergy may be diagnosed. This test is only performed under medical supervision.
The suspect foods are given orally (in the mouth) in little amounts and the quantity is built up gradually whilst symptoms are observed. The food may be given openly or ‘blinded’ (when people are unaware which food they are eating). Again, this should only be performed under medical supervision where medical facilities and resuscitation equipment are available.
IgE mediated food allergy
The reaction is immediate and can be severe.
This reaction involves IgE antibodies which are produced by your immune system. Conventional allergy testing can assist with diagnosis in conjunction with a detailed clinical history
Non-allergic food hypersensitivity
Also known as food intolerance where the immune system is not involved. Diagnosis is made by elimination and exclusion.
Food exclusion and reintroduction
The suspected food or foods are excluded for a period of time and symptoms observed and recorded.
If symptoms improve then the suspect food is reintroduced. If symptoms return then this would indicate that there is a problem with that specific food.
This can be extremely time consuming and is best carried out under the supervision of a registered dietitian, especially if children are involved. It is significant to ensure a well balanced nutritional intake during the test period and in the design of a diet where major food groups are excluded (e.g. dairy or wheat).
Foods that trigger allergies
170 foods are allergens, but most reactions are triggered by just a few foods.
The most common allergens are cows milk, eggs, peanuts, nuts, soy, wheat, fish and shellfish[6, 18].
Spices are found in every sorts of processed foods, cosmetics and dental products. However, they do not own to be marked on the packaging. This makes it hard for allergy sufferers to avoid certain spices. However, spice allergies are relatively rare. The most common are allergies to cinnamon and garlic, but more rarely there may be reactions to black pepper and vanilla.
Cow’s milk allergy
Cow’s milk allergy is the most common food allergy.
It generally develops in childhood before it disappears again during school age. Cow’s milk allergy sufferers reply to every dairy products, including cheese, yoghurt, butter and cream, and 92 percent are also allergic to goat’s milk. People with cow’s milk reactions should also avoid goat and sheep’s milk products.
Important: An allergy to cow’s milk is a completely diverse disease than lactose intolerance.
In nut allergy, doctors distinguish between allergies to peanuts — which are actually legumes — and other nuts that they refer to as tree nuts.
Every nut allergies tend to trigger relatively frequent violent reactions that even extend to anaphylactic shock[26,27].
Fish and shellfish allergy
A fish allergy is often only seen in adulthood. Affected people generally cannot tolerate any sort of fish. Most fish allergic individuals, however, can easily eat shellfish and vice versa.
Shellfish allergy also generally develops during adulthood. Shellfish include every crustaceans, including crabs and lobsters, molluscs (snails), including oysters, scallops and squid, as well as insects such as cockroaches and locusts.
Since house dust mites are crustaceans, shellfish allergy sufferers also often reply to home dust.
Wheat allergy most commonly develops in childhood and generally resolves itself before adulthood. 20 percent of wheat allergic individuals show cross-reactions with other cereals such as spelt or rye. But you should not extend your suspicions to every cereals, as this would restrict your diet too much. If in doubt, it is better to do an allergy test.
It’s best to make certain of what you can tolerate using a provocation test.
Important: A wheat allergy is not coeliac disease! As a wheat allergic individual you can still eat gluten-containing foods as endless as they do not contain wheat.
Chicken egg allergy
Chicken egg allergy is the second most common food allergy in childhood after cow’s milk allergy.
It too often resolves itself in adulthood.
And this is excellent to know: Some foods own a reduced potential to cause allergies when they are cooked. For example, numerous people with allergies can much better tolerate strongly heated milk or eggs used for baking. Peanuts, on the other hand, own an even higher allergic potential when roasted[22-24].
It is not the entire foodstuff that triggers an allergic reaction, but much rather certain proteins within them that act as allergens.
Sometimes diverse types of these proteins are so similar that the body can not tell them apart. In such a case, a cross-reaction may occur: The body is sensitised towards one allergen, but also reacts to the other. This happens between foods — and those allergic to peaches often also react to apples.
However, it can also happen that a pollen allergy leads to a cross-reaction with fruits, vegetables and nuts. And even latex often triggers cross-allergies — against kiwis, bananas and avocados.
Foods and their potential cross allergies:
Cross reaction to
Risk of cross-allergies
Watermelons, bananas, avocados
Apples, plums, cherries, pears
Apples, peaches, honey melons
Brazil nuts, cashews, hazelnuts
Kiwis, bananas, avocados