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
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