Food Sensitivities: Allergies and Intolerances

This is where the body produces IgE antibodies in response to an antigen. The antigen can enter the body through inhalation (eg pollen), ingestion (eg food), injection (eg bee sting) or skin contact.

Histamine is released, which give the symptoms of allergy. Symptoms of allergy from food include stomach cramps, hives (skin rash), nausea, vomiting, diarrhoea, shortness of breath and nasal congestion.

The most dangerous reaction is anaphylactic shock - rapid swelling of the lips, tongue and thoat which can lead to suffocation and death.

Other secondary effects include headaches, fatigue, joint and muscle aches, dizziness and depression.

Immediate allergies are usually able to be detected with a RAST test. The IgE response is triggered by proteins in foods (yes, wheat has proteins).

Common foods that may provoke an IgE response include foods such as milk, nuts, fish, wheat and eggs.

Milder symptoms can be helped by antihistamine medication. People that have an anaphylactic reaction should carry an Epipen in case of accidental exposure.

Most doctors are only familiar with classical allergies.

The lessor known but more common type of allergy is a delayed allergy. IgG antibodies are involved, and instead of histamine. other substances are released which cause inflammation and tissue damage. There may be a delay between ingestion of the offending food and presentation of symptoms, which can make it difficult to determine which food was responsible. Also the unpleasant effects may last several days.

Symptoms of delayed/IgG allergy include inflammation of body tissues, bloating, aches and pains, vomiting and diarrhoea, migraine, depression, skin rashes, rhinitis, asthma and fatigue.

IgG allergies are not picked up by the RAST test that doctors are most familiar with. They can be picked up by an ELISA test (which typically test for approximately 96 foods), but the food needs to have been ingested recently (in the few months prior), or it will give a false negative result. An ELISA test can be useful, but should be confirmed by an elimination diet - where food are removed from diet and then challenged.

Avoidance of the problematic foods should result in disappearance of symptoms. For mild responses, foods may be tolerated if rotated so eaten occasionally. Strong or very strong ELISA reactions are likely to be life-long delayed allergies.

Delayed allergies can be to any food. The ELISA test measures proteins in foods like fruits and vegetables also. Sometimes are person that has a delayed allergy to cow's milk may be able to tolerate goat's milk or sheep's milk. Or if they have a delayed allergy to one type of fish, they might be fine with other species of fish.

The inflammation from delayed allergies can result in weight gain (from permanent fluid retention). Delayed allergies are thought to trigger/advance autoimmune conditions like celiac disease, diabetes, thyroid disorders and arthritis.

Many foods contain natural histamines (amines) or cause the body to produce histamines when eaten (without involving the immune system, as in classical allergy).

The symptoms are identical to classical allergy, but arise from a different mechanism - a deficiency in enzymes that deactivate and eliminate histamine. Diamine oxidase (DAO) is the main enzyme responsible for the metabolism of ingested histamine.

A build up of histamine occurs in the body, which results in symptoms (which include itchy skin rash, rhinitis, aches and pains, stomach cramps, migraine, diarrhoea, asthma, depression, fatigue and in some cases, anaphylaxis).

The symptoms may be delayed, and present a few hours or days after ingestion.

Foods responsible for histamine reactions include over-ripe bananas, fermented foods such as red wine, fermented sauces, vinegar, aged cheeses, small-goods, long-life meat/fish, cocoa, chocolate and many fruits and vegetables (including strawberries, citrus, tomatoes).

Avoiding problematic foods results in resolution of symptoms. Anti-histamines can help with accidental (or intentional) exposures. Some companies have developed DAO enzyme capsules so that histamine foods can be enjoyed with less symptoms, but these drugs are expensive.

Histamine intolerance is not picked up in RAST or ELISA allergy tests, but can be determined from an elimination diet.

Alcohol and damaged guts (eg from inflammatory bowel disease or celiac disease) deplete DAO enzymes and make histamine intolerance worse. Many people with irritable bowel syndrome have histamine intolerance.

Vitamin B6 and vitamin C may be helpful in supporting enzyme function. Choose vitamins without flavours and other additives (which may be adding contributing to more sensitivities).

Salicylates are natural asprin-like compounds found in fruits and vegetables in varying amounts. Salicylate-sensitive individuals will also be sensitive to asprin and related compounds such as ibuprofen and non-steroidal anti-inflammatory drugs.

Foods high in natural salicylates include honey, mint, most fruit (especially when concentrated in fruit flavours), many vegetables. Foods with low to moderate levels of salicylates include potatoes, green beans, carrots, sweet potato, butternut pumpkin, red delicious apples, bananas.

Symptoms can include depression, joint and muscle pain, asthma, hives, behavioural problems, headaches and pseudo-anaphylaxis - ie the same kinds of symptoms as allergy and histamine intolerance.

Salicylates block vitamin K (which is needed for blood clotting). Salicylate-sensitive individuals may experience bleeding problems eg heavy menstrual bleeding and blood-nose. I wonder how many women have had hysterectomies that were actually salicylate sensitive?

An elimination diet can pin-point salicylate intolerance and a threshold determined to avoid problematic symptoms.

Salicylate-sensitive individuals are typically sensitive to fragrances (in toiletries and cleaning products), causing rhinitis, headache, nausea and other problems. A fragrance-free or low-fragrance home can provide relief. Fragrances in general are neurotoxins, so even those that are not acutely sensitive to salicylates might want to consider what toxins they are dousing their bodies and homes with.

Take a look at any processed food packet and there is likely to be a food list of 10 or more ingredients. Many artificial chemicals are added to make food look more appealing, last longer or taste "better".

Research studies have shown food additives trigger hyperactivity in children and other behavioural problems. Some countries have banned selected additives; most have not (including Australia). It is up to the consumer to become educated and informed. There have been campaigns by consumers for food companies to voluntarily withdraw artificial food colours.

There is no need to use artificial colours or preservatives - they are cheap and make more profit for food companies. There are ways to make food last without preservatives, and natural colours can be used (which are more expensive). There are plenty of companies producing tasty alternatives that are free of nasty additives.

No-one knows the long-term effects of consuming a diet rich in additives. The body needs to eliminate poisons, like artificial additives, and I expect there is a connection between health problems such as cancer and additives and other chemicals.

Additives that have caused distressing symptoms (like migraine, behavioural problems, hives etc) include:

• MSG (monosodium glutamate in soy sauce and chinese food)
• artificial colours (in sweets, custards, biscuits, drinks)
• artificial preservatives - benzoates & sulfites (in fruit drinks) sulfur dioxide (in dried fruit, breadcrumbs, wine), proprionates (in bread)
• flavour enhancers (in snack foods, fast foods, crackers, BBQ chicken).
• yellow natural colour 160b (annatto)

Other food intolerances include lactose and fructose, which result from enzyme deficiencies, often resulting from a damaged gut. Some of these intolerances are reversable eg as the gut heals.

Sensitivities can be determined from an elimination diet. Many children are being prescribed medication for ADHD when they have a food sensitivity at the root of their behavioural issues - they are having trouble eliminating poisons in foods.

A food aversion may sometimes related to a sensitivity to that food. My aversion to milk was well-founded - I knew it made me ill, and I hated the taste of milk, and years later, it was confirmed that I had a very strong delayed milk allergy. My son, who becomes sick from milk protein loved milk and craved it. An aversion or craving can sometimes give a clue to a food sensitivity. My favourite food was bread, and it turned out I was celiac (and because I was eating bread everyday, my chronic symptoms were not linked to diet).

More often than not, an aversion is related to the smell and/or texture of that food. Many children with an autism spectrum disorder such as Asperger's Syndrome have very acute senses, and are therefore very fussy about their food. They may reject food unless it has exactly the right texture, saltiness, sweetness etc. My son with Asperger's is like this, and is very frustrating to feed, as he self-limits his diet. In addition to gagging on meat fat (like I do), he gags on potato and rejects many foods. He will not eat chunky chips as they are too potato-like inside, but will eat shoe-strings. He used to gag on marshmallows and other foods with different texures. I have histamine sensitivity, and aged meat mades me nearly hurl.

My husband who does not have Asperger's has always hated vegetables and legumes (even though he is fine with amines and saliycates). My son hates vegetables too. It is thought there is a genetic basis for fussy eaters.

Of course, we've given our son the "children starving in third world countries" lecture, but I actually suspect my son would rather starve.