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3rd November 2010 Food Allergy – the widening perspective. The Allergy Research Foundation. 11th November 2010 – The foundations of ecological medicine – allergy. The British Society for Ecological Medicine. |
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Food Allergy – the widening perspective. The Allergy Research Foundation. The first presentation at this interesting conference was by paediatric gastroenterologist working at Great Ormond Street Hospital, Dr Neil Shah. It was entitled ‘Beyond IgE’ and looked at the food allergy related conditions suffered by the babies and children under his care which were not IgE related. These normally involved cow’s milk. He stressed that these were harder to diagnose and often went unrecognised, partly because symptoms could also be caused be a number of other conditions, partly because there are no validated tests for diagnosing non-IgE food sensitivity, but mainly because the food connection was rarely made. Symptoms can include gastroesophageal reflux, recurrent abdominal pain (Dr Shah suggested that babies who scream and arch their back are more likely to be suffering from allergy than from reflux), constipation and diarrhoea. Early onset constipation (while being breast fed), straining to produce normal stools and painful defecation should all alert doctors to the possibility of food allergy. He pointed up the connection between the immune system and the autonomic nervous system which controls the digestion, suggesting that the allergic reaction to a food could result in the immune system paralysing the muscles which normally control gut motility and the movement of food through the bowel thus causing constipation. Dr Shah also made the point that doctors should also be aware that allergy is a multi-system disease and that a child who suffers from one allergic condition (such as eczema) is much more likely to suffer from other allergic conditions (such as food allergy or allergic asthma) than a child with no primary allergy. Problems with diagnosis was also at the core of Professor Aziz’s Sheikh’s presentation. The Professor heads up the department of Primary Care Research and Development at Edinburgh University, which includes raising the awareness of allergy amongst GPs. As far as the average GP is concerned the lack of definitional clarity when dealing with allergy, the lack of effective testing mechanisms, the fact that many symptoms are shared by other conditions, a dearth of experience all make food allergy a condition that is often overlooked or discounted at primary care level. Professor Sheikh and his colleagues are working to improve this situation. Dr Simon Murch, Professor of Paediatric and Child Health at the University Hospital, Walsgrave was also concerned with diagnosis, the burden of his talk being the range of unusual symptoms which could suggest food allergy among children. He emphasised the critical importance of early recognition of food allergy in new born infants when watery diarrhoea and nappy rash can often be an unrecognised reaction to formula feed. The grizzly baby may have failed to establish any form of oral tolerance and their gut flora may already be seriously impaired. They may have pain at both ends of the digestive system and allergic gastroesophageal reflux combined with constipation. Other symptoms suggesting allergic reflux are dry skin, tonic neck posturing, abdominal distension, nappy rash and painful and strained defecation. When defecation is painful, the child will often bend over to try to stop the pain which makes defection even more difficult. Professor Murch also described a condition which he calls soft stool constipation, often related to cow’s milk intolerance or a family history of allergy, in which the child’s bowel is full of soft, rather than hard stools, which they are still unable to pass. Other symptoms he highlighted included the well, breast-fed infant with bloody stools (normally settles when the mother stops drinking cow’s milk), the infant made ill by fruit or sugar (hereditary fructose intolerance which needs immediate attention but is very rare) , the child with respiratory and ENT problems, nocturnal eneuresis and behavioural problems. Professor John Warner, Professor of Paediatrics at St Mary’s Hospital described his team’s research into the effect of food additives (mainly colourings) on the behaviour of otherwise normal children – as a result of which cautionary labels are now required on packets of coloured sweets. Histamine release, triggering behavioural change was noted within one hour of the ingestion of the additive. However it is not quite clear whether the colourings release the histamine or whether they reduce the activity of the enzyme which degrades histamine. Food additives are not, of course the only reason for increased histamine release which is also caused by exercise, infection, getting excited etc. However, any food or additive which affects histamine release can cause behavioural changes. The afternoon session included a talk by Dr Isabel Skypala on Oral Allergy Syndrome (which she prefers to call Pollen-Food Syndrome) in which a cross reaction between the pollen and a similar protein in a fruit causes hay fever sufferers to get a tingling sensation in the mouth. This is different from the true fruit allergies (especially to grape and peach) suffered in southern Europe. Whereas heating the fruit normally solves the problem for those suffering from Pollen Allergy Syndrome, it does not for those suffering from fruit allergy. Dr Skypala also touched on shellfish and mollusc allergies which are most common in adults. There are many cross reactions but there are also many types of shellfish and individuals can be allergic to different varieties which makes any tests for fish allergy quite unreliable. Indeed, she emphasised that a patient’s history combined with a challenge test was a far more reliable way to diagnose allergy than a test in which does not differentiate between sensitisation and an allergic reaction thus resulting in many false diagnoses. Dr Glenn Gibson of the Department of Food and Nutrition at the University of Reading then described how, despite thousands of published articles and over 700 positive human studies, the EFSA (the European Food Safety Authority) still refused to recognise the benefits of probiotics to the microbial health of the large intestine. However, he did also emphasise that probiotics can only deliver their benefit if they can reach the bowel intact and alive, so that they do need to be ‘good quality’. Amongst the benefits he described were improved digestion and intestinal transit and help in supporting the immune system. They also appear to benefit people with inflammatory bowel disease, reduce infant diarrhoea, help alleviate some of the gut symptoms in autistic children, reduce the incidence of c-difficile in a hospital situation and reduce the incidence of allergy if taken by pregnant mothers and infants. Dr Wesley Burks of the Pediatric Allergy and Immunology Department at Duke University North Carolina discussed the work that his team have been doing on immunotherapy for peanut allergy, both ingested and sublingual, both of which are proving encouraging. Similar work has been carried out in the UK on subcutaneous immunotherapy for hay fever and in Italy on egg and milk allergies. The team had found that whereas the sublingual method carries a much lower risk of side effects, it also achieves a lower degree of desensitisation. Dr Burks also discussed the Chinese herbal treatment which was first successfully used on mice in 2005 (see our report). Although the initial work was done on peanut allergy in mice, it is hoped that it would work with any food and therefore could be used by those with multiple food allergies. However, the active elements in the herbs are very specific and have been found only to be present in herbs grown in very specific areas, presumably with very specific soil and climatic conditions. The final presentation was by Professor Gideon Lack of the Paediatric unit at Guy’s and St Thomas’ Hospital in London who described the work his team was doing on the relationship between exposure and sensitisation – taking, as their starting point, the fact that although there are very high levels of peanut consumption amongst small children in Israel the incidence of peanut allergy is very low. Professor Lack suggested that, as with cat allergens, the children with the highest and the lowest exposure to the allergens are the least likely to become sensitised; those with moderate levels of exposure may be more likely to become sensitised. www.allergyresearchfoundation.org
The foundations of ecological medicine – allergy.
Unfortunately we only managed to sit in on a few of the presentations at this excellent two day training in ecological medicine but, as always with BSEM meetings, they were fascinating and thought provoking.
In ‘Applying immunology to the allergy patient’ Dr David Freed (of the Salford Allergy Clinic) sang a paean of praise to inflammation. Not chronic inflammation, that can scar and leave permanent damage, but acute inflammation – the hallmark of the allergic reaction. Inflammation, he claims, is good for you. As the body temperature rises, it destroys germs (which cannot survive higher temperatures). For example, as the temperature in a blocked nose rises, it kills temperature-sensitive viruses while sneezes and running noses get rids of the germs. It is the inflammation of the mucous surfaces in the body that produces most allergic symptoms but this inflammation has a biological purpose. Itchy skin encourages you to scratch; this gets rid of surface debris while encouraging healing lymph flow. He also suggested that the rise of hay fever (an allergic reaction to pollen) over the last 50–100 years is a result of pollution which has sensitised urban dwellers to pollen which does not affect country dwellers, who certainly come into contact with as much, if not more pollen than those living in towns.
Professor Vyvyan Howard, Professor of Bioimaging and leader of the Nano Systems Research Group at the University of Ulster addressed the subject of environmental toxicity. We carry thousands of chemicals in our bodies which get in by ingestion (pica), inhalation and through the skin. These include transient chemicals we can metabolise in around 72 hours and persistent chemicals which we can not metabolise at all. Persistent chemicals include organic pollutants (that usually incorporate a chlorine atom) many of which have now been banned under the UNEP convention. We have no easy mechanisms for removing these from the body. Before they were banned, over 1.5 millions tonnes of PCBs were manufactured each year and even now around 40 millions tonnes of organochlorines are created annually for plastics, solvents, pesticides etc. Dioxins are the highly toxic by products of the breakdown of these products, 80% off which comes from waste incineration, including clinical waste. Dioxins cannot be disposed of; all we can do is move them around. Even when we stop making them (assuming that we do not then create other chemicals with similar dioxin like activity) they will be around for a very long time. Moreover, they will, effectively, have completely changed the chemical environment of the planet, including all animal life, even that in the womb which had previously been thought to have been protected. Dioxins and humans These chemicals condense, become airborne and then get into the food chain. Concentrations increase as you go up the chain so humans, being at the top, receive significantly high doses. Since the chemicals are fat soluble they accumulate in fat. Alarmingly, they also cross into the placenta. A mother’s dioxin levels can halve during pregnancy as the chemicals are transferred to the foetus via the placenta. Even after birth, breast milk draws on fat stores (where dioxins are lodged) so yet more chemical will be transferred to the infant. Because of its body weight and its immunological immaturity, this infant will be far more vulnerable than its mother to this chemical load. Indeed, it has been suggested that because of the levels of chemicals detected in breast milk, mothers should limit the amount of breast milk given to their infants. While not going that far, Professor Howard recommends that new mothers should not diet as long as they continue to breast feed so that they do not mobilise the chemical-bearing fat stores within their bodies. Such recommendations are based on studies such as the recent 15-year follow up Dutch study that found that there was a dose relation to between chemical exposure and IQ levels with the highest exposure children logging in at four IQ points lower than the lower exposure children. BPA BPA (Bisphenol A) was discovered in the late 1800s but was only developed as an oestrogen compound in the 1930s. Natural oestrogen is not very bio-available to the foetus but manufactured oestrogen/BPA is and extraordinarily small amounts (parts per trillion) can have a significant effect on the body, especially in terms of cell signalling disruption. 50 micrograms/kilogram of body weight had been thought to be safe. However, it has been found that 20micrograms/kilogram can cross to mice in the womb and reduce the pups’ sperm count, so adult toxicological data can not be used in assessing safety levels for infants or the foetus. Moreover, there appears does not to be a linear dose response to these chemicals, but more of a U shape, while perceived doses may be also incorrect. For example, while babies’ bottles contain 30 parts of BPA per billion when new, as they are used and the plastic softens, the levels increase. It is now being realised that many chemicals which had been thought to be inert and harmless can, in fact, have effects even when ingested at extremely low levels. Cancer Professor Howard suggested that the increase in the rate of cancer, a disease of industrial nations, and the decreasing age of onset, may well be connected with chemical/environmental pollution, a view given weight by the recent massive study of over 45,000 pairs of identical twins, very, very few of whom shared a cancer.
Dr Peter Ohnsorge from Germany stressed the complexity of allergic illness pointing out that 30% of those with allergies also suffered from environmental illness, 4–9% severely. Many also suffered not only from chemical sensitivities but from chronic fatigue/ME and fibromyalgia – all inflammatory illnesses and all the sum of exposure and vulnerability/individual susceptibility. He deplored the current lack of risk assessment for environmental illness – information was received and applied long after the damage has already been done – as is all to clear from the stories of asbestos, Lindane, formaldehyde, PCBs, DDT etc etc. In environmental illness the chain of symptoms is usually very similar and tracking down the triggers involves a rigorous examination of the patient’s history and living/working conditions. Their house is particularly important especially now that houses are so well draught proofed so that pollution is trapped inside. Indoor moulds are especially important (they often produce skin reactions) as they may be hard to find but are very toxic. They are rarely seasonal so the assault on the body is constant and if the patient already suffers from genetic polymorphisms and depleted nutrition they will not be able to detox themselves. Dr Ohnsorge described the case one a child who was horrendously ill with multiple allergies, asthma, eczema etc whose illness was finally tracked to a peculiarly toxic mould growing in the corner of the loft in his family’s house. He also highlighted the possibility of indoor electro magnetic pollution – wifi, cordless phones etc. After the home, the patient’s work place needs to be examined with equal rigour and their diet needs to be assessed for nutritional sufficiency. If their nutritional intake is poor their body’s ability to detoxify itself will be severely hampered. He then stressed the important of inflammation and suggested that particular attention should be paid to the teeth as hidden dental inflammation can flag up a problem with chemicals such as BPA and titanium which are used in dental fillings and implants. He maintains that anything lodged in the body which des not belong there should be suspect. Finally, all stresses to which the patient is subjected need to be taken into account. These include physical, chemical, biological and psychological.
Others speakers on the day included Dr Len McEwen, Dr Andrew Goldsworthy (see our section on electromagnetic sensitivity for many of his articles), Dr Shideh Pouria of the Burghwood clinic, Dr Damien Downing, Margaret Moss (a regular contributor to foodsmatter.com), Dr Jean Monro of the Breakspear Hospital, Dr Rajendra Sharma and Dr Sarah Myhill. More from the British Society of Ecological Medicine
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