Food Allergy

Food Allergies

Food Allergies

Peanuts can leave you breathless. Cat dander can lead to itchy eyes, a stuffy nose, coughing and sneezing. And most of us have suffered through those seasonal allergies with horrible pollen counts. Learn more...

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Food Allergy

Asthma can be one of the major symptoms of chronic food allergy, which contributes to the total overall antigenic load of a patient. Food-mediated allergic reactions may become clinically apparent immediately or even hours to days later in a patient with asthma, manifested by specific production by B lymphocytes of IgE and IgG antibodies to food proteins. From 20 to 60 of patients with bronchoconstrictive symptoms are reported to develop these symptoms as a result of food ingestion.13 One study demonstrated that the elimination of previously determined food allergens early in life resulted in decreased asthma symptomatology as well as inhibiting the progression of allergic tendencies (represented by decreased production of total and specific IgE) compared to a control group that did not undergo such eliminations.14 Increased gastrointestinal (GI) permeability and GI symptomatology has been found in a larger percentage of patients with asthma compared to controls without asthma...

Irritable Bowel Syndrome

Allergic reactions in the gut have an estimated prevalence of approximately 1 -2 in adults. Clinical symptoms include abdominal pain, nausea, vomiting, cramping, and diarrhea. Intestinal mast cells and intestinal eosinophils have been shown to be involved in the pathogenesis of food-allergy-related enteropathy. In addition to classical IgE-dependent degranulation, other agonists, such as interleukin (IL)-4, have been demonstrated to activate mast cells.29,30 Because low-grade mucosal inflammation predominates in IBS, undiagnosed food allergies may play a role in the promotion and perpetuation of the low-grade inflammatory process.30,31 Food products have variously been reported as causing, perpetuating, or being used to treat IBS, and many patients with IBS report histories of food intolerance concomitant with IBS symptoms.31,32 A study with 150 IBS patients were ELISA tested and were randomized to receive either a diet excluding all foods to which they had tested positive or a...

Identifying Food Allergens

For determining the food antigens to which a patient is susceptible, food-allergy tests are performed to determine a patient's allergies sensitively and specifically. Modern serum testing, used with detailed history taking and analysis of a patient's symptomatology, can expedite a diagnosis of food allergy. This approach is helpful because symptoms of such allergies are typically quite difficult to isolate and explain via food-ingestion-related causes and effects, because of the delayed reactions that are typically involved. Laboratory and challenge tests can provide reliable information to help identify both suspected and unsuspected food allergens. Although standard laboratory tests, such as the RAST and ELISA are simple for a patient, tests that entail challenging a patient with antigenic foods, either orally or dermally, are much more difficult or may not provide adequate specificity to identify offending food allergens. For example, the two common offenders, wheat and soy, are so...

Lactosefree Bean a Boon for Lactose Intolerants

Soybean seeds are devoid of lactose sugar. Therefore, soy milk, being free from lactose - as compared to animal or human milk, which contain about 5-7 lactose - is an ideal substitute for lactose intolerants who are congeni-tally deficient in lactase enzymes. It is also recommended for adults who become malabsorbers of lactose with ageing. Furthermore, soy milk is nutritionally on a par with cow's milk. Globally, lactase deficiency varies across populations, ranging from 5 in northern Europe to 90 in southeastern countries. Lactose intolerance has been reported in South American Indians, South African Bantu, Nigerians, Australian Aborigines, Israeli Jews, African-Americans, northwestern Russians, Japanese, Thais and Malaysians. Tandon et al. (1981) reported the incidence of lactose intolerance to be in the magnitude of 66.6 for those from the south of India and 27.4 for those from the north.

Characterization of Protein Fractions

Proteomics offers an effective approach for identifying wheat allergens. 2-DGE was coupled with Edman microsequencing 50, 51 or MS 52 to identify wheat proteins involved in baker's asthma, an IgE-mediated allergy. Proteins that cross-reacted with sera from asthmatic patients include a-amylase inhibitor 50, 51 GAPDH, TPI, and serpin 52 and acyl-CoA oxidase and FBA 51 . Wheat food allergies are also IgE-mediated proteins that cross-react with sera from allergic patients include lipid transfer protein (LTP) as well as a-, P-, y-, and -gliadins 53 . Proteomic procedures are also being developed for the screening of allergens with S-S bonds 54 . Allergen research appears to be an especially promising area for applying proteomics to identify and characterize allergens in foods and food products.

The enzyme linked immunosorbent assay ELISA

For the RAST, possible allergens are affixed to a plate that is then saturated with a sample of serum from the patient. If the patient's serum contains an antibody that is specific to an affixed antigen, it will link to the antigen. Next, a small amount of radioactive, polyclonal antireagenic antibody is then added to the plate. Following a reaction and washing period, residual radiation is measured to determine what percentage of the radioactive antibody is bound to the linked antigen-antibody complex. Higher amounts of radioactive bonding equate to a greater amount of reactive antibody that is specific to tested allergens in the patient's serum. The RAST primarily measures IgE-mediated allergies, that is, immediate hypersensitivity. Being that a growing body of evidence cites IgG in food allergies, the RAST may not detect all food allergen reactions accurately. Oral provocation with suspected allergenic foods administered in a double-blinded, placebo-controlled test is widely...

Delayed Food Sensitivities And Allergies

In 1906, Clemens Von Pirquet, M.D., the noted Austrian pediatrician, coined the term allergy from the Greek alios (meaning changed or altered state) and ergon (meaning reaction or reactivity) to describe patients with excessive physiologic responses to substances in their environment. Currently, 50 million Americans suffer from allergies on a yearly basis, with allergy ranking as the fifth leading cause of chronic disease, and more than half of U.S. citizens test positive for one or more allergens.1 In fact, 16.7 million office visits to health care providers are attributed to allergic rhinitis alone.2 At all ages, allergic rhinitis without asthma is reported by nearly 90 people of every 1,000.3 In 1996, estimated U.S. health care expenditures attributable to sinusitis were more than 5.8 billion.4 Two recent estimates of allergy prevalence in the United States were 9 and 16 ,5 while the prevalence for specific allergic conditions, such as allergic rhinitis and atopic dermatitis, have...

The Complex Roles Of Immunoglobulins

Food allergies, including immediate hypersensitivity reactions involving IgE and other, delayed hypersensitivity reactions involving other immunoglobulins, contribute to immunemediated tissue injury and disease. IgE antibodies are thought to trigger allergic reactions when cross-linking occurs on GI mast cells, resulting in a cascade of histamines and leukotrienes. Histamine-receptor activation is one possible mechanism for underlying cellular pathways that cause the barrier function of the intestinal epithelium to break down.13 The onslaught of previously mentioned inflammatory allergic molecules and their alteration of intestinal permeability permit food macromolecules to pass through the mucosal serosa. Once food antigens are in circulation, they may predispose other organs and systems of the body to allergic reactions. In addition, IgG antibodies have been shown, experimentally, to increase the permeability of the intestinal wall.14 Increased intestinal permeability has been...


Limited evidence suggests that dietary restriction of gluten and casein may be beneficial in children with autism. A small controlled study found that such children showed significantly better development with a gluten- and casein-restricted diet than did controls.54 Food allergy may play a role in autistic symptomatology, as suggested by significantly increased levels of antibodies to casein, beta-lactoglobulin, and lactalbumin in autistic children than in controls, followed by reductions in behavioral symptoms with an eight-week elimination diet for these three food components.55 However, a small, double-blind, placebo-controlled study failed to find any significant changes in autistic children with a gluten- and casein-restricted diet, although the children's parents did report improvements in the children's conditions.56 Another study found behavioral improvement after six months in 60 of autistic children given a ketogenic diet.57

Migraine Headaches

The link between food allergy and migraine has long been dismissed by many general practitioners, who do not tend to treat their patients' migraine headaches as having food-allergy-based etiologies. However, various foods have been cited as causative agents including citrus fruits, tea, coffee, pork, chocolate, milk, nuts, vegetables, and cola drinks.28,29 In general, higher IgE incidence is no greater among people with migraine headaches than among the general population. However, this does not rule out food allergy as a cause of migraine headaches. There are various causes of migraines that are more appropriately labeled as food sensitivities to tyramine, phenylalanine, phenolic flavonoids, alcohol, and caffeine. In addition,


Rhamnosus, Lactobacillus sporenges, and Lactobacillus fermentum. Lactobacillus binds to the mucosal lining in the intestines. Here, they inhibit pathogenic bacteria by lactic acid and hydrogen peroxide synthesis, as well as preventing pathogenic bacteria from binding to the mucosal lining by competing for mucosal binding sites.38-40 Research has also suggested that Lactobacillus has immune-modulating effects, and is helpful in many GI conditions such as Crohn's disease, irritable bowel syndrome, food allergy, antibiotic-induced diarrhea, and pouchitis.41-43

Digestive Enzymes

Supplementation with digestive enzymes will help the natural enzymes secreted by the pancreas to properly digest carbohydrates, proteins, and fats. Natural digestive enzymes are often missing or inadequately secreted in patients with food allergies.51 Supplementation of these enzymes can decrease absorption of inappropriately large macromolecules from the intestines. These enzymes are often supplemented as combinations including lactase, sucrase, lipase, amylase, protease, maltase, phytase, and cellulase. Betaine hydrochloride supplementation may also be beneficial.


That is probably why babies are prone to milk and egg allergies. But it takes time and exposure to allergens to produce symptoms. Immigrants from Europe, where ragweed (Ambrosia) is relatively scarce, may not develop hay fever for years after moving to the U.S.A.

Oleosins and Allergy

Plant seeds and tree nuts are responsible for the vast majority of food allergies. The prevalence of peanut and tree nut allergy has doubled among the children in the United States from 1997 to 2002, reaching 1.2 75 . Considerable research has been conducted to identify and characterize nut and seed allergens 76 . Most of these allergens belong to the cupin and the prolamin superfamilies, but a new family, oleosin, has recently been identified 77 . The first suspicion of oleosin involvement in allergy was reported more than 10 years ago 78 , but awaited 2002 for formal evidence. Pons et al. 79 showed specific igE-binding with peanut oleosin in three of 14 sera of patients with allergic reaction to peanuts. Interestingly, the IgE binding was weak against oleosin monomers but stronger with proteins of HMW, presumed to be oleosin oligomers. The authors also argued for a possible cross-reactivity between oleosins from various seeds. More recently, oleosins were identified as allergens in...


Esophagitis is common with GERD and may be classified as erosive or nonerosive with the severity based on the number and location of mucosal breaks. Other types of esophagitis, such as eosinophilic esophagitis, present with similar symptoms as GERD and are commonly misdiagnosed. The common presentation of eosinophilic esophagitis is dysphagia and food impaction. Additional symptoms may include epigastric pain, emesis, weight loss, and failure to thrive.21 The diagnosis is based on a histologic finding of greater than 20 eosinophils per high-powered field in the esophageal squamous mucosa. This condition also presents with motor disturbances that may cause food impaction in the absence of strictures. Manometry shows high amplitude long-duration waves in the distal esophagus particularly at night. The symptoms often respond to elimination or elemental dietary regimens and antiallergy treatment.22 Standard skin-prick tests measure type 1 hypersensitivity reactions, which are typically...

Medicinal uses

There is no denying that soybean has many health benefits. These benefits are mainly derived from the quality of the soybean proteins and from the isoflavones, genistein and daidzein. Soybean has been shown to be beneficial in conditions of lactose intolerance, high cholesterol, heart disease, cancer, menopausal symptoms, osteoporosis and diabetes.


Atopy is a major predisposing factor for asthma, and environmental allergens are a causal factor for producing asthma. Food allergy is frequently underestimated in association with asthma, despite having been shown to trigger or exacerbate broncho-obstruction in 2 -8.5 of children with asthma.25 Sensitization of food can occur early in life, involving a T-cell response of the Th2 phenotype in addition to the commonly cited IgE-mediated hypersensitivity. Diagnosis of asthma-associated food allergy is important for children with respiratory symptoms, especially when asthma symptoms begin early on in life and when they are associated with other manifestations of food allergies. Elimination of food allergens early in infancy have resulted in improved clinical asthma manifestations as well as exerting a protective effect on the progression of allergic tendencies later in life, as evidenced by decreased production of both total and specific IgE.26


Atopic disease prevalence is increasing worldwide. Atopic eczema affects nearly 18 of infants in the first two years of life. It has been widely speculated that food allergies are the main cause of atopy. Strong associations between atopic eczema and IgE-mediated allergies to milk, eggs, and peanuts have been demonstrated. However, nearly two-thirds of patients with food allergies display no IgE sensitization to the instigating food proteins and symptoms either returned or were exacerbated upon administration of food-challenge tests.26,27 These patients with allergic reactions to the ingestion of specific foods did not display sensitized IgE to the foods, yet still had allergic reactions when the foods were reintroduced in their diets. Thus, such patients can be said to be allergic to the foods with no identifiable IgE antibodies, in essence, having hidden food allergies.''