Trends in Allergies and Trends in Allergies and Intolerances in Nutrition and Intolerances in Nutrition and

Food ServiceFood Service

Janice M. Joneja, Ph.D., RDJanice M. Joneja, Ph.D., RD

1010thth Annual Regional Nutrition and Food Service Conference Annual Regional Nutrition and Food Service ConferenceEdmonton 2006Edmonton 2006

22

Progress in the Past 5 YearsProgress in the Past 5 Years

Nearly 4% of North Americans have food allergies, Nearly 4% of North Americans have food allergies, many more than recorded in the pastmany more than recorded in the past– Incidence of food allergy much higher in children than Incidence of food allergy much higher in children than

adults (>8% compared to <2%)adults (>8% compared to <2%)

Prevalence of peanut allergy doubled in American Prevalence of peanut allergy doubled in American children younger than 5 years of age in the past 5 children younger than 5 years of age in the past 5 yearsyearsIncidence of food intolerances estimated to be up to Incidence of food intolerances estimated to be up to 50% of the population, but accurate figures are not 50% of the population, but accurate figures are not available because of the lack of appropriate testsavailable because of the lack of appropriate tests– Incidence of food intolerances much higher in adults than Incidence of food intolerances much higher in adults than

in childrenin children

Many food allergens have been characterized at the Many food allergens have been characterized at the molecular level, leading to increased understanding molecular level, leading to increased understanding of the causes of many allergic disordersof the causes of many allergic disorders

33

Management of Food Allergies and Management of Food Allergies and IntolerancesIntolerances

Management of food sensitivities Management of food sensitivities consists of:consists of:– Accurate identification of the food causing Accurate identification of the food causing

the problemthe problem– Educating clients on how to avoid relevant Educating clients on how to avoid relevant

allergens and intolerance triggers in foodsallergens and intolerance triggers in foods– Formulating appropriate diets to avoid the Formulating appropriate diets to avoid the

culprit foods and replacing them with foods culprit foods and replacing them with foods of equivalent nutritional valueof equivalent nutritional value

– Educating parents in measures to avoid Educating parents in measures to avoid sensitization of their at-risk babies sensitization of their at-risk babies

44

The Allergic DiathesisThe Allergic Diathesis

..

Food Allergy

Atopic dermatitis(Eczema)

Allergic rhinoconjunctivitis

(hay fever)

Asthma(cough;wheeze)

Gastrointestinal symptoms

Sleep deprivation

Anaphylaxis

Mental fogginess

Irritability

Fatigue

Food AllergyFood Allergy

Response of the Response of the Immune SystemImmune System

66

Priority Food Allergens In CanadaPriority Food Allergens In CanadaPeanutsPeanutsTree nuts (almonds, Brazil nuts, cashews, Tree nuts (almonds, Brazil nuts, cashews, hazelnuts (filberts), macadamia nuts, pecans, hazelnuts (filberts), macadamia nuts, pecans, pinenuts, pistachios, walnuts)pinenuts, pistachios, walnuts)Sesame seedsSesame seedsMilkMilkEggsEggsFish Fish Shellfish (e.g. clams, mussels, oysters, scallops Shellfish (e.g. clams, mussels, oysters, scallops and crustaceans (e.g. crab, crayfish, lobster, and crustaceans (e.g. crab, crayfish, lobster, shrimp) )shrimp) )SoySoyWheatWheatSulphitesSulphites

These Priority Allergens account for more than These Priority Allergens account for more than 95% of severe adverse reactions related to 95% of severe adverse reactions related to food allergensfood allergens

77

Additional Factors Involved in Symptoms Additional Factors Involved in Symptoms of Food Sensitivityof Food Sensitivity

Increased permeability of the digestive tractIncreased permeability of the digestive tract (leaky gut)(leaky gut)

– Inflammation:Inflammation:InfectionInfectionAllergyAllergyAutoimmune diseaseAutoimmune diseaseOther diseasesOther diseases

– Immaturity (in infants)Immaturity (in infants)– Alcohol consumptionAlcohol consumption

Physical exertion:Physical exertion:Exercise-induced anaphylaxisExercise-induced anaphylaxis

88

Additional Factors Involved in Additional Factors Involved in Symptoms of Food SensitivitySymptoms of Food Sensitivity

StressStress

Eating several different allergenic foods at the Eating several different allergenic foods at the same timesame time

Other allergies occurring at the same time Other allergies occurring at the same time (e.g. hay fever, asthma)(e.g. hay fever, asthma)

99

Classification of Food AllergensClassification of Food Allergens [Sampson 2003]:[Sampson 2003]:

Class 1:Class 1:– Direct sensitization via the gastrointestinal tract Direct sensitization via the gastrointestinal tract

after ingestionafter ingestion– Water-soluble proteins or glycoproteins Water-soluble proteins or glycoproteins – Stable to heat, proteases, and acidStable to heat, proteases, and acid– Many are lipid transfer proteinsMany are lipid transfer proteins

Class 2:Class 2:– Sensitization by inhalation of air-borne allergenSensitization by inhalation of air-borne allergen– Cross-reaction to foods containing structurally Cross-reaction to foods containing structurally

identical proteinsidentical proteins– Heat labileHeat labile– Many are pathogenesis-related proteinsMany are pathogenesis-related proteins

1010

Oral Allergy SyndromeOral Allergy Syndrome(OAS)(OAS)

OAS refers to clinical symptoms in the OAS refers to clinical symptoms in the mucosa of the mouth and throat that:mucosa of the mouth and throat that:Result from direct contact with a food allergenResult from direct contact with a food allergenIn an individual who also exhibits allergy to In an individual who also exhibits allergy to inhaled allergens.inhaled allergens.Usually pollens (pollinosis) are the primary Usually pollens (pollinosis) are the primary allergensallergensPollens usually trigger rhinitis or asthmaPollens usually trigger rhinitis or asthmaOccurs most frequently in adultsOccurs most frequently in adults

1111

Oral Allergy SyndromeOral Allergy SyndromeCharacteristicsCharacteristics

Inhaled pollen allergens sensitize Inhaled pollen allergens sensitize tissues of the upper respiratory tract tissues of the upper respiratory tract Tissues of the respiratory tract are Tissues of the respiratory tract are adjacent to oral tissues, and the mucosa adjacent to oral tissues, and the mucosa is continuousis continuousSensitization of one leads to Sensitization of one leads to sensitization of the othersensitization of the otherOAS symptoms are mild in contrast to OAS symptoms are mild in contrast to primary food allergens and occur only in primary food allergens and occur only in and around the mouth and in the throatand around the mouth and in the throat

1212

Oral Allergy SyndromeOral Allergy Syndrome

The foods cause symptoms in the oral cavity The foods cause symptoms in the oral cavity and local tissues immediately on contact:and local tissues immediately on contact:– SwellingSwelling– Throat tighteningThroat tightening– TinglingTingling– ItchingItching– “ “Blistering”Blistering”

Foods most frequently associated with OAS Foods most frequently associated with OAS are mainly fruits, a few vegetables, and nutsare mainly fruits, a few vegetables, and nuts

1313

Oral Allergy SyndromeOral Allergy SyndromeAllergensAllergens

Pollens and foods that cause OAS are Pollens and foods that cause OAS are usually botanically unrelatedusually botanically unrelatedOccurs most frequently in persons allergic Occurs most frequently in persons allergic to birch and alder pollensto birch and alder pollensAlso occurs with allergy to:Also occurs with allergy to:– Ragweed pollenRagweed pollen– Mugwort pollenMugwort pollen– Grass pollensGrass pollens

1414

Oral Allergy SyndromeOral Allergy SyndromeCross-reacting allergensCross-reacting allergens

Birch pollens with:Birch pollens with:

– AppleApple– Stone Fruits (Apricot, Peach, Nectarine, Plum, Cherry)Stone Fruits (Apricot, Peach, Nectarine, Plum, Cherry)– Kiwi FruitKiwi Fruit– Orange Orange - Peanut- Peanut - Almond- Almond– Melon Melon - Hazelnut- Hazelnut - Walnut- Walnut– Watermelon Watermelon - Carrot- Carrot - Anise- Anise– Potato Potato - Celery- Celery - Caraway seed- Caraway seed– TomatoTomato - Parsnip- Parsnip– Green pepperGreen pepper - Parsley- Parsley– CuminCumin - - BeansBeans– CorianderCoriander - - PeasPeas– DillDill - - LentilsLentils– Sunflower seedSunflower seed - Soy- Soy

1515

Oral Allergy SyndromeOral Allergy SyndromeCross-reacting allergensCross-reacting allergens

Ragweed pollen with:Ragweed pollen with:– BananaBanana– CantaloupeCantaloupe– HoneydewHoneydew– WatermelonWatermelon– Other MelonsOther Melons– Zucchini (Courgette)Zucchini (Courgette)– CucumberCucumber

1616

Expression of OAS SymptomsExpression of OAS Symptoms

Oral reactivity to the food significantly Oral reactivity to the food significantly decreases when food is cookeddecreases when food is cookedReactivity of the antigen depends on Reactivity of the antigen depends on ripenessripeness– Antigen becomes more potent as the plant Antigen becomes more potent as the plant

material agesmaterial ages

People differ in the foods which trigger People differ in the foods which trigger OAS, even when they are allergic to the OAS, even when they are allergic to the cross-reacting pollenscross-reacting pollens– Foods contain an antigen that is structurally Foods contain an antigen that is structurally

similar to the allergenic pollen, but not all similar to the allergenic pollen, but not all people will develop OAS to all foods having that people will develop OAS to all foods having that antigenantigen

1717

Identification of Foods ResponsibleIdentification of Foods Responsible for OAS Symptoms for OAS Symptoms

Skin tests will identify the allergenic plant pollenSkin tests will identify the allergenic plant pollenSkin testing has not been successful in identifying Skin testing has not been successful in identifying persons who react to cross-reacting food antigenspersons who react to cross-reacting food antigens– Plant antigens are unstable and do not survive the Plant antigens are unstable and do not survive the

process of antigen preparationprocess of antigen preparation– Crushing plant material leads to release of phenols and Crushing plant material leads to release of phenols and

degradative enzymesdegradative enzymes

Prick + prick technique are more reliable than Prick + prick technique are more reliable than standard skin testsstandard skin tests– Lancet is inserted in raw fruit or vegetable, withdrawn Lancet is inserted in raw fruit or vegetable, withdrawn

and then used to prick the person’s skinand then used to prick the person’s skin

1818

Latex-Fruit SyndromeLatex-Fruit Syndrome

Allergy to latex often starts as: Allergy to latex often starts as:

Contact allergy to a latex protein, usually Contact allergy to a latex protein, usually through:through:– Abraded (non-intact) skinAbraded (non-intact) skin– Mucous membraneMucous membrane– Exposed tissue (e.g. during surgery)Exposed tissue (e.g. during surgery)

Inhalant allergy:Inhalant allergy:– Inhaled powder from latex glovesInhaled powder from latex gloves

1919

Latex AllergyLatex AllergyCross-reacting allergensCross-reacting allergens

As antigen comes into contact with As antigen comes into contact with immune cells, repeated exposure leads to immune cells, repeated exposure leads to IgE mediated allergyIgE mediated allergy

Proteins in foods with the same structure Proteins in foods with the same structure as proteins in latex trigger the same IgE as proteins in latex trigger the same IgE response when they are eatenresponse when they are eaten

In extreme cases can cause anaphylactic In extreme cases can cause anaphylactic reactionreaction

2020

Latex AllergyLatex AllergyRelated foodsRelated foods

Examples of foods that have been shown to contain Examples of foods that have been shown to contain proteins similar in structure to latex:proteins similar in structure to latex:

– Banana Banana - Mango - Mango - Tomato- Tomato

– Citrus Fruits Citrus Fruits - Melon - Melon - Celery- Celery

– Kiwi Fruit Kiwi Fruit - Pineapple - Pineapple - Avocado - Avocado

– Fig Fig - Papaya - Papaya - Tree Nuts- Tree Nuts

– Passion Fruit Passion Fruit - Peach - Peach - Chestnut - Chestnut

– GrapesGrapes - Potato - Potato - Peanut- Peanut

2121

Common allergens in unrelated plant Common allergens in unrelated plant materials: materials: SummarySummary

OAS and latex allergy are examples of OAS and latex allergy are examples of conditions in which common antigens, conditions in which common antigens, expressed in botanically unrelated plants, expressed in botanically unrelated plants, are capable of eliciting a hypersensitivity are capable of eliciting a hypersensitivity reactionreaction

In practice, when a specific plant food In practice, when a specific plant food elicits an allergic response, foods in the elicits an allergic response, foods in the same botanic family rarely elicit allergysame botanic family rarely elicit allergy

Food IntolerancesFood Intolerances

Biochemical and Physiological Biochemical and Physiological ResponsesResponses

2323

Symptoms of Carbohydrate IntoleranceSymptoms of Carbohydrate Intolerance

Watery loose stool (diarrhea)Watery loose stool (diarrhea)

Abdominal bloating and pressureAbdominal bloating and pressure

Cramping pain in abdomenCramping pain in abdomen

FlatulenceFlatulence

VomitingVomiting

Poor weight gainPoor weight gain

2424

Cause of Carbohydrate Cause of Carbohydrate IntoleranceIntolerance

Lack of the enzyme that digests the Lack of the enzyme that digests the carbohydratecarbohydrateLactose intolerance is due to the lack of Lactose intolerance is due to the lack of lactase:lactase:– Milk sugar (lactose) is not digestedMilk sugar (lactose) is not digested

Sucrose intolerance is lack of the enzyme Sucrose intolerance is lack of the enzyme sucrasesucrase– Sucrose (table sugar; syrup of all types; some Sucrose (table sugar; syrup of all types; some

fruits) is not digestedfruits) is not digested

2525

Symptoms of Carbohydrate IntoleranceSymptoms of Carbohydrate Intolerance

Reddening and soreness of skin around the Reddening and soreness of skin around the anus and on the buttocks due to acid (pH less anus and on the buttocks due to acid (pH less than 6) stool in children. than 6) stool in children. – Adults rarely develop high acid stoolAdults rarely develop high acid stool

Abdominal fullness, bloating, and cramping Abdominal fullness, bloating, and cramping within 5-30 minutes after eating within 5-30 minutes after eating Diarrhea Diarrhea Lactose intolerance is the most common Lactose intolerance is the most common conditioncondition

2626

Management of Lactose IntoleranceManagement of Lactose Intolerance

Only the milk sugar, lactose, needs to be avoidedOnly the milk sugar, lactose, needs to be avoidedThis is not a milk allergy: This is not a milk allergy: – Milk proteins are toleratedMilk proteins are tolerated

Lactose occurs in the whey (liquid) fraction of milkLactose occurs in the whey (liquid) fraction of milkMilk products free from lactose and free from whey Milk products free from lactose and free from whey are safeare safeThese foods include:These foods include:– Milk treated with lactase (LactaidMilk treated with lactase (Lactaid; Lacteeze; Lacteeze))– Hard cheeses (whey is removed; casein remains Hard cheeses (whey is removed; casein remains

and is fermented to form cheese)and is fermented to form cheese)– Many people tolerate yogurt, where lactose is Many people tolerate yogurt, where lactose is

broken down by bacterial enzymesbroken down by bacterial enzymes

2727

Reactive Chemicals in FoodsReactive Chemicals in Foods

May act on the body in two ways:May act on the body in two ways:– chemical acts directly on body tissues rather chemical acts directly on body tissues rather

like a druglike a drug– chemical reacts with a system (stops or chemical reacts with a system (stops or

enhances the process) that acts on the body enhances the process) that acts on the body tissuetissue

Symptoms occur when the body is unable Symptoms occur when the body is unable to get rid of the chemical quickly enoughto get rid of the chemical quickly enough– The level in the body rises and the symptoms The level in the body rises and the symptoms

that develop are due to the excessthat develop are due to the excess

2828

HistamineHistamine Histamine reactions can be clinically Histamine reactions can be clinically

indistinguishable from food allergyindistinguishable from food allergy Hives, facial swelling, and headaches are Hives, facial swelling, and headaches are

examples of histamine excessexamples of histamine excess Tests for food allergy are usually negativeTests for food allergy are usually negative Histamine sensitivity is becoming recognized Histamine sensitivity is becoming recognized

as a disease entity quite distinct from allergyas a disease entity quite distinct from allergy Sensitivity may be deficiency in the enzymes Sensitivity may be deficiency in the enzymes

that break down excess histaminethat break down excess histamine Histamine intolerance can exacerbate Histamine intolerance can exacerbate

allergy to the extent of eliciting an allergy to the extent of eliciting an anaphylactic reaction when the two anaphylactic reaction when the two conditions occur togetherconditions occur together

2929

Sources of Histamine in FoodsSources of Histamine in Foods

Fermented foods:Fermented foods:– Microbial activity on proteins produces histamineMicrobial activity on proteins produces histamine

Examples:Examples:

CheeseCheese

Processed meats and sausages:Processed meats and sausages:

SalamiSalami

BolognaBologna

PepperoniPepperoni

Vinegar and foods containing vinegar:Vinegar and foods containing vinegar:

PicklesPickles

3030

Sources of Histamine in FoodsSources of Histamine in Foods

Fermented beverages:Fermented beverages:– WineWine

– Beer, ale, lagerBeer, ale, lager

Fish and shellfish:Fish and shellfish:– Incorrectly storedIncorrectly stored

– Bacteria in the intestine of the fish start to break down Bacteria in the intestine of the fish start to break down fish proteinfish protein

3131

Sources of Histamine in FoodsSources of Histamine in Foods

Some foods contain high levels of histamine Some foods contain high levels of histamine naturally, especially: naturally, especially:

Spinach Spinach EggplantEggplant Berries (Berries (strawberries and raspberriesstrawberries and raspberries)) TomatoTomato Citrus fruitsCitrus fruits (orange; lemon; lime; grapefruit) (orange; lemon; lime; grapefruit)

Some foods may release histamine by a Some foods may release histamine by a mechanism which is only partially understood mechanism which is only partially understood

example: egg white example: egg white

3232

Other Sources of HistamineOther Sources of Histamine

Micro-organisms in the body:Micro-organisms in the body:– Certain types of bacteria in the large bowel Certain types of bacteria in the large bowel

use undigested food material for their use undigested food material for their reproduction and growthreproduction and growth

– People with these micro-organisms absorb People with these micro-organisms absorb histamine from their own intestinehistamine from their own intestine

– It is possible that probiotic bacteria could be It is possible that probiotic bacteria could be used to displace these strainsused to displace these strains

3333

Tyramine sensitivityTyramine sensitivity

Symptoms when tyramine-rich foods Symptoms when tyramine-rich foods are eaten:are eaten:– Sharp rise in blood pressureSharp rise in blood pressure– HeadacheHeadache

Caused by:Caused by: Deficiency in the enzymes that break Deficiency in the enzymes that break

down excess tyraminedown excess tyramine

3434

Tyramine in FoodsTyramine in Foods

Formed by microbial action in food Formed by microbial action in food preparation:preparation:– cheesecheese– winewine– yeast extractyeast extract– vinegarvinegarSmall amounts occur naturally in some Small amounts occur naturally in some foodsfoods::– chicken liverchicken liver - eggplant- eggplant– avocadoavocado - tomato- tomato– bananabanana - plum- plum

3535

Sensitivity to Food AdditivesSensitivity to Food Additives

Characteristics common to Characteristics common to persons sensitive to food persons sensitive to food additivesadditives::

– History of asthma and hay fever History of asthma and hay fever

– Occasionally hives and facial Occasionally hives and facial swellingswelling

– Aspirin sensitiveAspirin sensitive

3636

Additives Most Frequently Causing Additives Most Frequently Causing IntolerancesIntolerances

Tartrazine (and other artificial food colours)Tartrazine (and other artificial food colours)

Preservatives:Preservatives:

– SulphitesSulphites

– BenzoatesBenzoates

– SorbatesSorbates

Monosodium glutamate (MSG)Monosodium glutamate (MSG)

Nitrates and nitritesNitrates and nitrites

3737

Symptoms of Tartrazine SensitivitySymptoms of Tartrazine Sensitivity

Asthma in asthmaticsAsthma in asthmatics

UrticariaUrticaria

AngioedemaAngioedema

NauseaNausea

Migraine headachesMigraine headaches

Evidence of hyperactivity in childrenEvidence of hyperactivity in children

Excess tartrazine may increase levels of Excess tartrazine may increase levels of inflammatory mediators in allergy, such as:inflammatory mediators in allergy, such as:– leukotrienes – important mediators in asthmaleukotrienes – important mediators in asthma– histaminehistamine

3838

Foods Frequently Containing Foods Frequently Containing TartrazineTartrazine

Soft drinksSoft drinks

Liqueurs and cordialsLiqueurs and cordials

Candy and confectioneryCandy and confectionery

Ready-to-eat cerealsReady-to-eat cereals

Jams and jelliesJams and jellies

Ice cream, sherbet, milk shakesIce cream, sherbet, milk shakes

Commercial gravies and soup mixesCommercial gravies and soup mixes

Flavor packetsFlavor packets

Pickles, relish, salad dressingsPickles, relish, salad dressings

Prepared baked goodsPrepared baked goods

Smoked fish and fish productsSmoked fish and fish products

3939

Foods Frequently Containing Foods Frequently Containing TartrazineTartrazine

Snack foodsSnack foodsMeal replacementsMeal replacementsAny food containing “artificial color” may contain Any food containing “artificial color” may contain tartrazine unless it is labeled “tartrazine free”tartrazine unless it is labeled “tartrazine free”

Non-food items:Non-food items:Medications (prescription and OTC)Medications (prescription and OTC)Vitamin and mineral supplementsVitamin and mineral supplementsToiletries and cosmeticsToiletries and cosmetics

4040

Sulphite SensitivitySulphite Sensitivity

Most common in asthmaticsMost common in asthmaticsSteroid-dependent asthmatics are most at riskSteroid-dependent asthmatics are most at riskAdverse reactions to sulphites is estimated to be as Adverse reactions to sulphites is estimated to be as high as 1% of the U.S. populationhigh as 1% of the U.S. populationSulphite sensitivity in non-asthmatics is considered to Sulphite sensitivity in non-asthmatics is considered to be quite rarebe quite rareSymptoms occur in most organ systems:Symptoms occur in most organ systems:– LungsLungs– Gastrointestinal tractGastrointestinal tract– Skin and mucous membranesSkin and mucous membranes– Life-threatening anaphylactic reactions in Life-threatening anaphylactic reactions in

asthmatics have been recorded, but occur very asthmatics have been recorded, but occur very rarely.rarely.

4141

Symptoms Reported in Sulphite Symptoms Reported in Sulphite SensitivitySensitivity

Urticaria (hives)Urticaria (hives)

Angioedema (swelling, especially of the Angioedema (swelling, especially of the mouth and face)mouth and face)

Contact dermatitisContact dermatitis

Anaphylaxis (in asthmatics)Anaphylaxis (in asthmatics)

Anaphylactoid reaction (non-asthmatics)Anaphylactoid reaction (non-asthmatics)

4242

Forms of Sulphites Permitted in Forms of Sulphites Permitted in FoodsFoods

Sulphites are permitted in the form of:Sulphites are permitted in the form of:– Sodium metabisulphiteSodium metabisulphite– Potassium metabisulphitePotassium metabisulphite– Sodium bisulphiteSodium bisulphite– Potassium bisulphitePotassium bisulphite– Sodium sulphiteSodium sulphite– Sodium dithioniteSodium dithionite– Sulphurous acidSulphurous acid– Sulphur dioxideSulphur dioxide

4343

Forms of Sulphites Permitted in Forms of Sulphites Permitted in FoodsFoods

Use of sulphites on fresh fruits and vegetables Use of sulphites on fresh fruits and vegetables not allowed except on sliced raw potatoes and not allowed except on sliced raw potatoes and raw grapesraw grapes

Sulphites are not allowed on raw foods in Sulphites are not allowed on raw foods in salad bars or for sale in markets, with the salad bars or for sale in markets, with the above exceptionsabove exceptions

U.S. government regulations require sulphites U.S. government regulations require sulphites in excess of 10 ppm in manufactured foods in excess of 10 ppm in manufactured foods and beverages, including alcoholic beverages, and beverages, including alcoholic beverages, to be listed on labelsto be listed on labels

Sulphites are permitted in a wide rage of Sulphites are permitted in a wide rage of dried, frozen, and processed foods, dried, frozen, and processed foods, sweeteners, and snack foodssweeteners, and snack foods

4444

Sulphite SensitivitySulphite Sensitivity

There is no evidence that avoiding all sources of There is no evidence that avoiding all sources of dietary sulphites improves asthmadietary sulphites improves asthma

Exposure to sulphiting agents poses very little risk for Exposure to sulphiting agents poses very little risk for individuals who are not sensitive to sulphitesindividuals who are not sensitive to sulphites

Sulphites in foods are not denatured by cooking Sulphites in foods are not denatured by cooking

Sulphites avidly bind to several substances in foods, Sulphites avidly bind to several substances in foods, such as protein, starch, and sugars. They are not such as protein, starch, and sugars. They are not removed by washingremoved by washing

Sulphates do not cause the same adverse reactions Sulphates do not cause the same adverse reactions as sulphites. They are inert in the body and need not as sulphites. They are inert in the body and need not be avoided by people who are sensitive to sulphitesbe avoided by people who are sensitive to sulphites

4545

Benzoate Intolerance Benzoate Intolerance SymptomsSymptoms

Reported to induce:Reported to induce:– UrticariaUrticaria– AngioedemaAngioedema– AsthmaAsthma– RhinitisRhinitis– Purpura (allergic vasculitis)Purpura (allergic vasculitis)– Hyperactivity in childrenHyperactivity in children

May lead to increase in histamineMay lead to increase in histamine

4646

Benzoates and Parabens:Benzoates and Parabens:Use in FoodsUse in Foods

One of the most commonly used food One of the most commonly used food additives worldwideadditives worldwide

Benzoic acid and sodium benzoate Benzoic acid and sodium benzoate (benzoates) are used as antibacterial and (benzoates) are used as antibacterial and antimycotic agents in foods and beveragesantimycotic agents in foods and beverages

Benzoates are most effective as preserving Benzoates are most effective as preserving agents at an acidic pHagents at an acidic pH

Benzoyl peroxide is used as a bleaching Benzoyl peroxide is used as a bleaching agent, especially in white flour, white bread, agent, especially in white flour, white bread, and some white Italian cheesesand some white Italian cheeses

4747

Benzoates Benzoates Naturally occurringNaturally occurring

Benzoates occur widely in nature as simple Benzoates occur widely in nature as simple salts (sodium, potassium), esters, and amidessalts (sodium, potassium), esters, and amides

Natural benzoates are present at the highest Natural benzoates are present at the highest levels in:levels in:

– Cinnamon, Clove, Anise, NutmegCinnamon, Clove, Anise, Nutmeg

– PrunesPrunes

– Black TeaBlack Tea

– BerriesBerries

Especially Raspberry and CranberryEspecially Raspberry and Cranberry

4848

Monosodium Glutamate (MSG)Monosodium Glutamate (MSG)

Flavouring common in Chinese cooking Flavouring common in Chinese cooking and increasingly used to flavour and increasingly used to flavour Western foodsWestern foods

Sensitive individuals report a variety of Sensitive individuals report a variety of symptoms that are usually classified as symptoms that are usually classified as “Chinese Restaurant Syndrome” (also “Chinese Restaurant Syndrome” (also known as Kwok’s syndrome)known as Kwok’s syndrome)

4949

Most Frequently Reported Symptoms of Most Frequently Reported Symptoms of Sensitivity to Monosodium GlutamateSensitivity to Monosodium Glutamate

– Headache, back of head and neckHeadache, back of head and neck

– Numbness of faceNumbness of face

– Tingling/burning of face and chestTingling/burning of face and chest

– Tightness in chestTightness in chest

– Rapid heartbeatRapid heartbeat

– Nausea, diarrhea, stomach acheNausea, diarrhea, stomach ache

– Weakness, balance problemsWeakness, balance problems

– ConfusionConfusion

– Blurred visionBlurred vision

– Chills, shakes, perspirationChills, shakes, perspiration

– Difficulty breathingDifficulty breathing

– Asthma in asthmaticsAsthma in asthmatics

5050

MSG SensitivityMSG Sensitivity

Experts are widely divided on the Experts are widely divided on the subject of MSG sensitivitysubject of MSG sensitivity

One review “led to the conclusion that One review “led to the conclusion that ‘Chinese Restaurant Syndrome’ is an ‘Chinese Restaurant Syndrome’ is an anecdote applied to a variety of anecdote applied to a variety of postprandial illnesses”postprandial illnesses”

Some clinicians have estimated that the Some clinicians have estimated that the prevalence of “Chinese Restaurant prevalence of “Chinese Restaurant Syndrome” may be as high 1.8% of the Syndrome” may be as high 1.8% of the adult populationadult population

5151

Characteristics of MSG SensitivityCharacteristics of MSG Sensitivity

Alcohol may increase the rate of absorption of Alcohol may increase the rate of absorption of MSG and increase the MSG and increase the severityseverity and and rate of rate of onsetonset of symptoms of symptoms

Symptoms usually occur about 30 minutes Symptoms usually occur about 30 minutes after eating a meal high in MSGafter eating a meal high in MSG

Asthma occurs 1 to 2 hours after MSG Asthma occurs 1 to 2 hours after MSG ingestion, and even as long as 12 hours lateringestion, and even as long as 12 hours later

Vitamin B6 (pyridoxine) deficiency may be a Vitamin B6 (pyridoxine) deficiency may be a factor in some MSG sensitive peoplefactor in some MSG sensitive people

5252

Sources of MSGSources of MSG

Present in many flavouring mixtures:Present in many flavouring mixtures:

AccentAccent ZestZest

Gourmet powderGourmet powder GlutaveneGlutavene

GlutacylGlutacyl Chinese seasoningChinese seasoning

SubuSubu VetsinVetsin

AjinomotoAjinomoto Kombu extractKombu extract

Mei-jingMei-jing Wei-jingWei-jing

RL-50RL-50

Hydrolysed vegetable protein (HVP)Hydrolysed vegetable protein (HVP)

Hydrolysed plant protein (HPP)Hydrolysed plant protein (HPP)

““Natural flavour” (may be HVP)Natural flavour” (may be HVP)

5353

Sources of MSGSources of MSG

Used as a flavouring in foods, especially in Used as a flavouring in foods, especially in Chinese cooking, in canned foods (e.g. Chinese cooking, in canned foods (e.g. soups), and restaurant mealssoups), and restaurant meals

Some sensitive individuals will also react to Some sensitive individuals will also react to monopotassium glutamatemonopotassium glutamate

Several foods, such as tomato, mushrooms, Several foods, such as tomato, mushrooms, and cheese contain natural glutamatesand cheese contain natural glutamates

5454

Nitrate and Nitrite SensitivityNitrate and Nitrite Sensitivity

Nitrates and nitrites are used in foods as Nitrates and nitrites are used in foods as preservativespreservatives

Particularly protective against Particularly protective against Clostridium Clostridium botulinumbotulinum

Impart flavour and preserve colour in Impart flavour and preserve colour in manufactured foods, especially meatsmanufactured foods, especially meats

SymptomsSymptoms

Reports of headache in sensitive individualsReports of headache in sensitive individuals

5555

Nitrates and Nitrites in FoodsNitrates and Nitrites in Foods

Labels list sodium nitrate, potassium nitrate, Labels list sodium nitrate, potassium nitrate, sodium nitrite, and potassium nitrite in sodium nitrite, and potassium nitrite in manufactured foodsmanufactured foods

Present at high levels in processed meats:Present at high levels in processed meats:

• • PepperoniPepperoni • • FrankfurtersFrankfurters

• • Hot Dog WienersHot Dog Wieners • • SalamiSalami

• • BolognaBologna • • Other Luncheon Other Luncheon MeatsMeats

• • BaconBacon • • HamHam

• • Smoked FishSmoked Fish • • Some Imported CheesesSome Imported Cheeses

5656

Nitrates in Plant FoodsNitrates in Plant Foods

Nitrates occur naturally in plants: the major Nitrates occur naturally in plants: the major source is nitrate-containing fertilizerssource is nitrate-containing fertilizers

Some species of plants tend to accumulate Some species of plants tend to accumulate nitrates more than others:nitrates more than others:

• • SpinachSpinach • • CeleryCelery

• • BeetsBeets • • LettuceLettuce

• • RadishesRadishes • • CollardsCollards

• • Turnip GreensTurnip Greens • • EggplantEggplant

5757

SummarySummaryFood allergy is most prevalent in babies and childrenFood allergy is most prevalent in babies and childrenFood intolerances predominate in adultsFood intolerances predominate in adults

Infant onset food allergy is mostly due to Class 1 Infant onset food allergy is mostly due to Class 1 allergensallergens– Sensitization is by ingestion of allergenSensitization is by ingestion of allergen

Adult onset food allergy mostly due to Class 2 allergensAdult onset food allergy mostly due to Class 2 allergens– Sensitization by allergen inhalation or contact Sensitization by allergen inhalation or contact

Food allergy: must avoid all sources of the allergenFood allergy: must avoid all sources of the allergenFood intolerance: dose relatedFood intolerance: dose related

Several additional factors sometimes required to elicit Several additional factors sometimes required to elicit symptoms symptoms Food intolerance can exacerbate food allergyFood intolerance can exacerbate food allergy