Trends in Allergies and Intolerances in Nutrition and Food Service Janice M. Joneja, Ph.D., RD 10th Annual Regional Nutrition and Food Service Conference Edmonton 2006

Progress in the Past 5 Years Nearly 4% of North Americans have food allergies, many more than recorded in the past Incidence of food allergy much higher in children than adults (>8% compared to <2%) Prevalence of peanut allergy doubled in American children younger than 5 years of age in the past 5 years Incidence of food intolerances estimated to be up to 50% of the population, but accurate figures are not available because of the lack of appropriate tests Incidence of food intolerances much higher in adults than in children Many food allergens have been characterized at the molecular level, leading to increased understanding of the causes of many allergic disorders

Management of Food Allergies and Intolerances Management of food sensitivities consists of: Accurate identification of the food causing the problem Educating clients on how to avoid relevant allergens and intolerance triggers in foods Formulating appropriate diets to avoid the culprit foods and replacing them with foods of equivalent nutritional value Educating parents in measures to avoid sensitization of their at-risk babies

The Allergic Diathesis Atopic dermatitis (Eczema) . Sleep deprivation Irritability Gastrointestinal symptoms Food Allergy Mental fogginess Fatigue Asthma (cough; wheeze) Allergic rhinoconjunctivitis (hay fever) Anaphylaxis

Response of the Immune System Food Allergy Response of the Immune System

Priority Food Allergens In Canada Peanuts Tree nuts (almonds, Brazil nuts, cashews, hazelnuts (filberts), macadamia nuts, pecans, pinenuts, pistachios, walnuts) Sesame seeds Milk Eggs Fish Shellfish (e.g. clams, mussels, oysters, scallops and crustaceans (e.g. crab, crayfish, lobster, shrimp) ) Soy Wheat Sulphites These Priority Allergens account for more than 95% of severe adverse reactions related to food allergens

Additional Factors Involved in Symptoms of Food Sensitivity Increased permeability of the digestive tract (leaky gut) Inflammation: Infection Allergy Autoimmune disease Other diseases Immaturity (in infants) Alcohol consumption Physical exertion: Exercise-induced anaphylaxis

Additional Factors Involved in Symptoms of Food Sensitivity Stress Eating several different allergenic foods at the same time Other allergies occurring at the same time (e.g. hay fever, asthma)

Classification of Food Allergens [Sampson 2003]: Direct sensitization via the gastrointestinal tract after ingestion Water-soluble proteins or glycoproteins Stable to heat, proteases, and acid Many are lipid transfer proteins Class 2: Sensitization by inhalation of air-borne allergen Cross-reaction to foods containing structurally identical proteins Heat labile Many are pathogenesis-related proteins

Oral Allergy Syndrome (OAS) OAS refers to clinical symptoms in the mucosa of the mouth and throat that: Result from direct contact with a food allergen In an individual who also exhibits allergy to inhaled allergens. Usually pollens (pollinosis) are the primary allergens Pollens usually trigger rhinitis or asthma Occurs most frequently in adults

Oral Allergy Syndrome Characteristics Inhaled pollen allergens sensitize tissues of the upper respiratory tract Tissues of the respiratory tract are adjacent to oral tissues, and the mucosa is continuous Sensitization of one leads to sensitization of the other OAS symptoms are mild in contrast to primary food allergens and occur only in and around the mouth and in the throat

Oral Allergy Syndrome The foods cause symptoms in the oral cavity and local tissues immediately on contact: Swelling Throat tightening Tingling Itching “Blistering” Foods most frequently associated with OAS are mainly fruits, a few vegetables, and nuts

Oral Allergy Syndrome Allergens Pollens and foods that cause OAS are usually botanically unrelated Occurs most frequently in persons allergic to birch and alder pollens Also occurs with allergy to: Ragweed pollen Mugwort pollen Grass pollens

Oral Allergy Syndrome Cross-reacting allergens Birch pollens with: Apple Stone Fruits (Apricot, Peach, Nectarine, Plum, Cherry) Kiwi Fruit Orange - Peanut - Almond Melon - Hazelnut - Walnut Watermelon - Carrot - Anise Potato - Celery - Caraway seed Tomato - Parsnip Green pepper - Parsley Cumin - Beans Coriander - Peas Dill - Lentils Sunflower seed - Soy

Oral Allergy Syndrome Cross-reacting allergens Ragweed pollen with: Banana Cantaloupe Honeydew Watermelon Other Melons Zucchini (Courgette) Cucumber

Expression of OAS Symptoms Oral reactivity to the food significantly decreases when food is cooked Reactivity of the antigen depends on ripeness Antigen becomes more potent as the plant material ages People differ in the foods which trigger OAS, even when they are allergic to the cross-reacting pollens Foods contain an antigen that is structurally similar to the allergenic pollen, but not all people will develop OAS to all foods having that antigen

Identification of Foods Responsible for OAS Symptoms Skin tests will identify the allergenic plant pollen Skin testing has not been successful in identifying persons who react to cross-reacting food antigens Plant antigens are unstable and do not survive the process of antigen preparation Crushing plant material leads to release of phenols and degradative enzymes Prick + prick technique are more reliable than standard skin tests Lancet is inserted in raw fruit or vegetable, withdrawn and then used to prick the person’s skin

Latex-Fruit Syndrome Allergy to latex often starts as: Contact allergy to a latex protein, usually through: Abraded (non-intact) skin Mucous membrane Exposed tissue (e.g. during surgery) Inhalant allergy: Inhaled powder from latex gloves

Latex Allergy Cross-reacting allergens As antigen comes into contact with immune cells, repeated exposure leads to IgE mediated allergy Proteins in foods with the same structure as proteins in latex trigger the same IgE response when they are eaten In extreme cases can cause anaphylactic reaction

Latex Allergy Related foods Examples of foods that have been shown to contain proteins similar in structure to latex: Banana - Mango - Tomato Citrus Fruits - Melon - Celery Kiwi Fruit - Pineapple - Avocado Fig - Papaya - Tree Nuts Passion Fruit - Peach - Chestnut Grapes - Potato - Peanut

Common allergens in unrelated plant materials: Summary OAS and latex allergy are examples of conditions in which common antigens, expressed in botanically unrelated plants, are capable of eliciting a hypersensitivity reaction In practice, when a specific plant food elicits an allergic response, foods in the same botanic family rarely elicit allergy

Biochemical and Physiological Responses Food Intolerances Biochemical and Physiological Responses

Symptoms of Carbohydrate Intolerance Watery loose stool (diarrhea) Abdominal bloating and pressure Cramping pain in abdomen Flatulence Vomiting Poor weight gain

Cause of Carbohydrate Intolerance Lack of the enzyme that digests the carbohydrate Lactose intolerance is due to the lack of lactase: Milk sugar (lactose) is not digested Sucrose intolerance is lack of the enzyme sucrase Sucrose (table sugar; syrup of all types; some fruits) is not digested

Symptoms of Carbohydrate Intolerance Reddening and soreness of skin around the anus and on the buttocks due to acid (pH less than 6) stool in children. Adults rarely develop high acid stool Abdominal fullness, bloating, and cramping within 5-30 minutes after eating Diarrhea Lactose intolerance is the most common condition

Management of Lactose Intolerance Only the milk sugar, lactose, needs to be avoided This is not a milk allergy: Milk proteins are tolerated Lactose occurs in the whey (liquid) fraction of milk Milk products free from lactose and free from whey are safe These foods include: Milk treated with lactase (Lactaid; Lacteeze) Hard cheeses (whey is removed; casein remains and is fermented to form cheese) Many people tolerate yogurt, where lactose is broken down by bacterial enzymes

Reactive Chemicals in Foods May act on the body in two ways: chemical acts directly on body tissues rather like a drug chemical reacts with a system (stops or enhances the process) that acts on the body tissue Symptoms occur when the body is unable to get rid of the chemical quickly enough The level in the body rises and the symptoms that develop are due to the excess

Histamine Histamine reactions can be clinically indistinguishable from food allergy Hives, facial swelling, and headaches are examples of histamine excess Tests for food allergy are usually negative Histamine sensitivity is becoming recognized as a disease entity quite distinct from allergy Sensitivity may be deficiency in the enzymes that break down excess histamine Histamine intolerance can exacerbate allergy to the extent of eliciting an anaphylactic reaction when the two conditions occur together

Sources of Histamine in Foods Fermented foods: Microbial activity on proteins produces histamine Examples: Cheese Processed meats and sausages: Salami Bologna Pepperoni Vinegar and foods containing vinegar: Pickles

Sources of Histamine in Foods Fermented beverages: Wine Beer, ale, lager Fish and shellfish: Incorrectly stored Bacteria in the intestine of the fish start to break down fish protein

Sources of Histamine in Foods Some foods contain high levels of histamine naturally, especially: Spinach Eggplant Berries (strawberries and raspberries) Tomato Citrus fruits (orange; lemon; lime; grapefruit) Some foods may release histamine by a mechanism which is only partially understood example: egg white

Other Sources of Histamine Micro-organisms in the body: Certain types of bacteria in the large bowel use undigested food material for their reproduction and growth People with these micro-organisms absorb histamine from their own intestine It is possible that probiotic bacteria could be used to displace these strains

Tyramine sensitivity Symptoms when tyramine-rich foods are eaten: Sharp rise in blood pressure Headache Caused by: Deficiency in the enzymes that break down excess tyramine

Tyramine in Foods Formed by microbial action in food preparation: cheese wine yeast extract vinegar Small amounts occur naturally in some foods: chicken liver - eggplant avocado - tomato banana - plum

Sensitivity to Food Additives Characteristics common to persons sensitive to food additives: History of asthma and hay fever Occasionally hives and facial swelling Aspirin sensitive

Additives Most Frequently Causing Intolerances Tartrazine (and other artificial food colours) Preservatives: Sulphites Benzoates Sorbates Monosodium glutamate (MSG) Nitrates and nitrites

Symptoms of Tartrazine Sensitivity Asthma in asthmatics Urticaria Angioedema Nausea Migraine headaches Evidence of hyperactivity in children Excess tartrazine may increase levels of inflammatory mediators in allergy, such as: leukotrienes – important mediators in asthma histamine

Foods Frequently Containing Tartrazine Soft drinks Liqueurs and cordials Candy and confectionery Ready-to-eat cereals Jams and jellies Ice cream, sherbet, milk shakes Commercial gravies and soup mixes Flavor packets Pickles, relish, salad dressings Prepared baked goods Smoked fish and fish products

Foods Frequently Containing Tartrazine Snack foods Meal replacements Any food containing “artificial color” may contain tartrazine unless it is labeled “tartrazine free” Non-food items: Medications (prescription and OTC) Vitamin and mineral supplements Toiletries and cosmetics

Sulphite Sensitivity Most common in asthmatics Steroid-dependent asthmatics are most at risk Adverse reactions to sulphites is estimated to be as high as 1% of the U.S. population Sulphite sensitivity in non-asthmatics is considered to be quite rare Symptoms occur in most organ systems: Lungs Gastrointestinal tract Skin and mucous membranes Life-threatening anaphylactic reactions in asthmatics have been recorded, but occur very rarely.

Symptoms Reported in Sulphite Sensitivity Urticaria (hives) Angioedema (swelling, especially of the mouth and face) Contact dermatitis Anaphylaxis (in asthmatics) Anaphylactoid reaction (non-asthmatics)

Forms of Sulphites Permitted in Foods Sulphites are permitted in the form of: Sodium metabisulphite Potassium metabisulphite Sodium bisulphite Potassium bisulphite Sodium sulphite Sodium dithionite Sulphurous acid Sulphur dioxide

Forms of Sulphites Permitted in Foods Use of sulphites on fresh fruits and vegetables not allowed except on sliced raw potatoes and raw grapes Sulphites are not allowed on raw foods in salad bars or for sale in markets, with the above exceptions U.S. government regulations require sulphites in excess of 10 ppm in manufactured foods and beverages, including alcoholic beverages, to be listed on labels Sulphites are permitted in a wide rage of dried, frozen, and processed foods, sweeteners, and snack foods

Sulphite Sensitivity There is no evidence that avoiding all sources of dietary sulphites improves asthma Exposure to sulphiting agents poses very little risk for individuals who are not sensitive to sulphites Sulphites in foods are not denatured by cooking Sulphites avidly bind to several substances in foods, such as protein, starch, and sugars. They are not removed by washing Sulphates do not cause the same adverse reactions as sulphites. They are inert in the body and need not be avoided by people who are sensitive to sulphites

Benzoate Intolerance Symptoms Reported to induce: Urticaria Angioedema Asthma Rhinitis Purpura (allergic vasculitis) Hyperactivity in children May lead to increase in histamine

Benzoates and Parabens: Use in Foods One of the most commonly used food additives worldwide Benzoic acid and sodium benzoate (benzoates) are used as antibacterial and antimycotic agents in foods and beverages Benzoates are most effective as preserving agents at an acidic pH Benzoyl peroxide is used as a bleaching agent, especially in white flour, white bread, and some white Italian cheeses

Benzoates Naturally occurring Benzoates occur widely in nature as simple salts (sodium, potassium), esters, and amides Natural benzoates are present at the highest levels in: Cinnamon, Clove, Anise, Nutmeg Prunes Black Tea Berries Especially Raspberry and Cranberry

Monosodium Glutamate (MSG) Flavouring common in Chinese cooking and increasingly used to flavour Western foods Sensitive individuals report a variety of symptoms that are usually classified as “Chinese Restaurant Syndrome” (also known as Kwok’s syndrome)

Most Frequently Reported Symptoms of Sensitivity to Monosodium Glutamate Headache, back of head and neck Numbness of face Tingling/burning of face and chest Tightness in chest Rapid heartbeat Nausea, diarrhea, stomach ache Weakness, balance problems Confusion Blurred vision Chills, shakes, perspiration Difficulty breathing Asthma in asthmatics

MSG Sensitivity Experts are widely divided on the subject of MSG sensitivity One review “led to the conclusion that ‘Chinese Restaurant Syndrome’ is an anecdote applied to a variety of postprandial illnesses” Some clinicians have estimated that the prevalence of “Chinese Restaurant Syndrome” may be as high 1.8% of the adult population

Characteristics of MSG Sensitivity Alcohol may increase the rate of absorption of MSG and increase the severity and rate of onset of symptoms Symptoms usually occur about 30 minutes after eating a meal high in MSG Asthma occurs 1 to 2 hours after MSG ingestion, and even as long as 12 hours later Vitamin B6 (pyridoxine) deficiency may be a factor in some MSG sensitive people

Sources of MSG Present in many flavouring mixtures: Accent Zest Gourmet powder Glutavene Glutacyl Chinese seasoning Subu Vetsin Ajinomoto Kombu extract Mei-jing Wei-jing RL-50 Hydrolysed vegetable protein (HVP) Hydrolysed plant protein (HPP) “Natural flavour” (may be HVP)

Sources of MSG Used as a flavouring in foods, especially in Chinese cooking, in canned foods (e.g. soups), and restaurant meals Some sensitive individuals will also react to monopotassium glutamate Several foods, such as tomato, mushrooms, and cheese contain natural glutamates

Nitrate and Nitrite Sensitivity Nitrates and nitrites are used in foods as preservatives Particularly protective against Clostridium botulinum Impart flavour and preserve colour in manufactured foods, especially meats Symptoms Reports of headache in sensitive individuals

Nitrates and Nitrites in Foods Labels list sodium nitrate, potassium nitrate, sodium nitrite, and potassium nitrite in manufactured foods Present at high levels in processed meats: • Pepperoni • Frankfurters • Hot Dog Wieners • Salami • Bologna • Other Luncheon Meats • Bacon • Ham • Smoked Fish • Some Imported Cheeses

Nitrates in Plant Foods Nitrates occur naturally in plants: the major source is nitrate-containing fertilizers Some species of plants tend to accumulate nitrates more than others: • Spinach • Celery • Beets • Lettuce • Radishes • Collards • Turnip Greens • Eggplant

Summary Food allergy is most prevalent in babies and children Food intolerances predominate in adults Infant onset food allergy is mostly due to Class 1 allergens Sensitization is by ingestion of allergen Adult onset food allergy mostly due to Class 2 allergens Sensitization by allergen inhalation or contact Food allergy: must avoid all sources of the allergen Food intolerance: dose related Several additional factors sometimes required to elicit symptoms Food intolerance can exacerbate food allergy