ADVANCED DIPLOMA IN PRINCIPLES OF NUTRITION

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1 ADVANCED DIPLOMA IN PRINCIPLES OF NUTRITION BY LAUREN OWENS RD BSC (HONS) Human Nutrition and DIetetics Course Educators: Thomas Woods, William Eames BY LAUREN

2 Special Diets Semester : Lesson 2 Food Allergies and Intolerances Course Educator: Lauren Owens BSc (Hons.) Human Nutrition and lauren.owens@shawacademy.com

3 Lesson 2 Learning Outcomes Food Hypersensitivity Food Allergy e.g. Cow s Milk Allergy Food Hypersensitivity Diagnosis Food Exclusion diets

5 Facts and Statistics Number of people with food allergies is growing but with no clear reason as to WHY?! More than 30% of the world s population is affected by allergies with approx. 250 million people thought to be affected 1 in 13 children under 18 suffer from food allergies Every 3 minutes, a food allergy sends someone to the emergency department Genetics Your risk of having food allergies is higher if you have a parent who suffers from any type of allergic disease (asthma, eczema, food allergies, or environmental allergies such as hay fever) Environment The Hygiene Hypothesis- Inadequate exposure to environmental micro-organisms may therefore result in the immune system of atopic children developing a tendency towards allergy. Epigenetics- genes turned on and off by environmental factors e.g food

6 Food Hypersensitivity

7 Question Time??? Are food allergy and food intolerance the same thing?? Answer.NO

8 Food Hypersensitivity

Top Food Allergens 8 foods account for 90% of all food-allergic reactions Estimated Prevalence 1. Peanut- 0.6-1.3% 2. Tree nuts- 0.4-0.6% 3. Fish- 0.4% 4.

10 Top Food Allergens 8 foods account for 90% of all food-allergic reactions Estimated Prevalence 1. Peanut % 2. Tree nuts % 3. Fish- 0.4% 4. Crustacean shellfish (crab, crayfish, lobster, shrimp) 1.2% 5. All seafood: 0.6% in children and 2.8% in adults 6. Milk and egg: approx. 1-2% for young children and % of the general population

11 Why Do Allergies Occur? 'inappropriate response by the body to a perfectly harmless substance'. Triggers immune response T-cell lymphocytes, which recognise allergens and react by producing cytotoxic substances or triggering inflammatory Production of inappropriately high titres of antibodies (IgE) B cell lymphocytes IgE antibodies which attach to 'mast' cells and, in turn, precipitate a release of histamine

12 Why Do Allergies Occur? Histamine- causes a contraction of the muscles around the air passages (an attack of breathlessness or asthma), local swelling and skin irritation, and, if the attack is serious enough, a drop in blood pressure

Anaphylaxis Most extreme form of allergic reaction Obvious symptoms (throat swelling/ hoarseness, wheezing, fainting & low blood pressure) Treated with

13 Anaphylaxis Most extreme form of allergic reaction Obvious symptoms (throat swelling/ hoarseness, wheezing, fainting & low blood pressure) Treated with Adrenaline/ Epinephrine Teenagers and young adults with food allergies are at the highest risk of fatal food-induced anaphylaxis Rapid in onset and may cause death

Non-allergic Food Hypersensitivity Often confused with allergic reactions No immunological mechanism involved Similar symptoms - vomiting, diarrhoea, rashes Also called food intolerance/

15 Non-allergic Food Hypersensitivity Often confused with allergic reactions No immunological mechanism involved Similar symptoms - vomiting, diarrhoea, rashes Also called food intolerance/ sensitivities Often manifest as a result or symptom of another medical condition or illness The acute effects can be severe - in some cases hypotension and anaphylactic reactions can occur

16 Food Allergy or Intolerance? Intolerance Usually comes on gradually Significant amounts of the food may need to be eaten May only happen when you eat the food often Usually not life threatening Allergy Comes on suddenly Triggered by small amounts of food Happens every time you eat the food Can be life threatening

17 Diagnosis of Food Hypersensitivity Clinical History Diagnostic tests Food Exclusion

wheel caused by food allergen should be interpreted in relation to the size of the negative control Easy

18 Diagnostic Tests Skin prick test- Measures specific IgE attached to mast cells in the skin Detects IgE mediated food allergy A positive (histamine) and negative (saline) control should always be used Size of the wheel caused by food allergen should be interpreted in relation to the size of the negative control Easy method to screen for patients with IgE mediated sensitivity to foods In general, wheal size >3mm- considered positive

19 IgE test - determines levels of circulating specific IgE to allergen in circulation Patch test - used for diagnosis of more delayed reactions such as allergic dermatitis Other diagnostic tests - still in experimental stage and not routinely used in the diagnosis of Food hypersensitivity

comprehensive information detailing both obvious and less obvious sources of the food Require information on reading labels

20 Food Exclusion Diets 1. Single exclusion diet: excludes all sources of a single food Can be very difficult in practice Patients require clear but comprehensive information detailing both obvious and less obvious sources of the food Require information on reading labels Guidance on suitable alternatives for excluded food 2. Multiple food exclusion diet: excludes a number of foods at the same time Used when a dietary link is suspected but not identified No set rules on which foods to exclude Practice varies by centre

Few Foods Diet and Monitoring More restrictive than a multiple exclusion diet Provides rapid symptom relief Excludes most foods Foods included are those

21 Few Foods Diet and Monitoring More restrictive than a multiple exclusion diet Provides rapid symptom relief Excludes most foods Foods included are those which rarely provoke sensitivity Practice varies between treatment centres Usually comprise 1 or 2 meats, a selection of starchy foods, vegetables ad some fruits

Few Foods Diet and Monitoring Both socially and nutritionally restricting Requires considerable commitment from patient Do not continue for more than 2-3 weeks

22 Few Foods Diet and Monitoring Both socially and nutritionally restricting Requires considerable commitment from patient Do not continue for more than 2-3 weeks Once symptom relief is obtained, foods reintroduced singly Monitoring- degree of effectiveness Keep a daily record of symptoms Record details of frequency and severity

Food Exclusion in the Management of Food Hypersensitivity To diagnose and treat hypersensitivity Complete avoidance can be difficult Avoidance of one type of food-little nutritional significance if

23 Food Exclusion in the Management of Food Hypersensitivity To diagnose and treat hypersensitivity Complete avoidance can be difficult Avoidance of one type of food-little nutritional significance if similar food can be eaten Exclusion of entire food group can have major impacts nutritionally Some single foods can have a large knock on effect e.g. nuts present in lots of food Food exclusions should be reviewed as they can remit with time Need to establish each patient s tolerance levels

24 Confirmation of Diagnosis Medically supervised food challenge Open food challenges Single-blind placebo-controlled food challenge Double-blind placebo-controlled food challenge

Prevention of Food Allergy Allergic disease such as asthma, rhinitis, eczema and food allergies increasing in both developed and developing world Different factors related to

25 Prevention of Food Allergy Allergic disease such as asthma, rhinitis, eczema and food allergies increasing in both developed and developing world Different factors related to development of allergic diseases: 1. Genetics 2. Exposure to allergens 3. Development of the immune response 4. Family history- individual more at risk of developing allergic diseases

Prevention of Food Allergy Role of maternal diet during pregnancy and breastfeeding and weaning in development of allergies - still uncertain Some

26 Prevention of Food Allergy Role of maternal diet during pregnancy and breastfeeding and weaning in development of allergies - still uncertain Some research suggests that avoiding allergens during pregnancy may have a negative effect Promising research that probiotics may be helpful - to be confirmed

Allergy Prevention Advice American Academy of Paediatrics Advice for infants at risk - where both parents or parent and sibling have documented disease Exclusive breastfeeding for up to 6 months

27 Allergy Prevention Advice American Academy of Paediatrics Advice for infants at risk - where both parents or parent and sibling have documented disease Exclusive breastfeeding for up to 6 months Alternatives if breastfeeding not possible/sufficient, use a formula with proven reduced allergenicity - this must be confirmed with GP advice Goat s and soya formula NOT suitable replacement for babies Breastfeeding does have some protective effect on the development of allergic disease and that this effect is greater when there is a family history of atopic disease Up to1/3 of infants will develop cow s milk allergy during exclusive breastfeeding

Breastfeeding and Weaning Guidelines For Allergy Prevention The American Academy of Paediatrics recommend: For High Risk Infants: Do not introduce solid

28 Breastfeeding and Weaning Guidelines For Allergy Prevention The American Academy of Paediatrics recommend: For High Risk Infants: Do not introduce solid food until 6 months Do not introduce cow s milk until 1 year Do not introduce egg until 2 years Do not introduce peanuts, tree nuts and fish until 3 years

avoid peanuts whilst breastfeeding Eat a healthy, balanced diet More information is needed

29 Breastfeeding and Weaning Guidelines For mothers of infants at high risk of developing atopy (During breastfeeding) : No evidence of benefit from avoiding specific foods May be helpful to avoid peanuts whilst breastfeeding Eat a healthy, balanced diet More information is needed regarding n-3 fatty acid consumption, probiotics, and vitamin and mineral intake in the prevention of allergic disease

Cow s Milk Allergy Characterised by gastrointestinal symptoms: Vomiting Diarrhoea Irritability Failure to thrive Sometimes more severe reactions: Anaphylaxis (life-threatening allergic reaction)

30 Cow s Milk Allergy Characterised by gastrointestinal symptoms: Vomiting Diarrhoea Irritability Failure to thrive Sometimes more severe reactions: Anaphylaxis (life-threatening allergic reaction) Facial swelling, hives (red itchy lumps) on the body, streaming nose, sickness and vomiting, or diarrhoea, Wheezing/ coughing/ breathing problems Usually develops in early infancy More delayed response: Eczema/ colic, poor growth, diarrhoea/ constipation Can be IgE-mediated food allergy, non-ige-mediated food allergy or non-allergic food hypersensitivity (e.g. lactose intolerance)

Management of Cow s Milk Allergy Treatment: complete avoidance of cow s milk protein Ensure provision of suitable formula alternative - soya not recommended Soya should never be introduced before 6

31 Management of Cow s Milk Allergy Treatment: complete avoidance of cow s milk protein Ensure provision of suitable formula alternative - soya not recommended Soya should never be introduced before 6 months of age Secondary lactose intolerance is common but temporary Goat s and sheep milk not suitable alternatives Specialised formulas available for babies - prescribed by Doctor Risk of nutritional deficiency (energy and calcium) when milk is eliminated from the diet Delayed growth can occur Important that diet remains free of cow s milk protein - from obvious and less obvious sources

32 Exclusion of Cow s Milk General Guidance Exclude Examples of foods to exclude Notes Cow s milk Dairy products Milk or milk derivatives in manufactured foods Liquid whole, semi-skimmed or skimmed milk Evaporated or condensed milk Dried full-fat or skimmed milk powder UHT powder Butter, margarine or fat spreads containing milk derivatives Cheese and cheese spreads Yoghurt Fromage frais, crème fraiche, cream, ice cream May be described on ingredients lists as: Milk, milk solids, non-fat milk solids, milk protein, skimmed milk, skimmed milk powder, casein or caseinates, hydrolysed casein, whey, whey solids, buttermilk lactose, milk sugar, whey sugar, whey syrup sweetener Goat s and sheep milk should not be used as an alternative to cow s milk. They are unsuitable for people requiring total exclusion of lactose or galactose Butter and hard cheeses can be used by people with mild/moderate lactose intolerance It may not be necessary to exclude lactose and other milk sugars in all cases of cow milk allergy but, for practical purposes, their presence is usually taken as indicative of the presence of milk, and foods containing them are excluded. Lactose in flavourings and medications may be a problem to some severely allergic patients

Tips For a Milk Free Diet 1. Read all food ingredient labels and look out for allergy information- check every time as sometimes company s change their ingredients 2.

33 Tips For a Milk Free Diet 1. Read all food ingredient labels and look out for allergy information- check every time as sometimes company s change their ingredients 2. Avoid foods which are sold loose or without a label where you are unsure if it contains milk 3. Avoid foods with may contain traces of milk 4. Avoid cross contamination with milk when preparing food 5. Ensure the diet contains adequate calcium from other nonmilk sources 6. Remember cow s milk allergy is different to lactose intolerance so just because it is lactose free does not mean it will be cow s milk free

34 Reintroduction of Milk Cow s milk allergy is often transitory Should be challenged every 6-12 months In the majority of cases cow s milk allergy will have resolved by 3 years Should be carried out under MEDICAL SUPERVISION

36 In Conclusion Food hypersensitivity can have both an allergic (immune response) and non-allergic response (food intolerance) Allergens should be excluded from the diet to prevent allergic response which can be life threatening Allergen diagnosis tests should always be done under medical supervision

Recordings are uploaded within 24 hours of the completion of each

37 Next Steps Try attend all of the sessions live and see your knowledge grow Practical lesson 2 will continue on this subject Recordings are uploaded within 24 hours of the completion of each live session Further reading links are available if you wish to learn more

38 To expand upon the subjects covered in todays lesson: Further Learning Basic nutrition- Diploma in Nutrition Weight loss- Ultimate weight Loss Programme

39 Advanced Course Resources Free Short Videos Topical Items that Pop Up Frequently Easy way of communicating that free content is available without spamming you!!!! Facebook: Before we begin let us gauge your experience level

40 Contact us anytime on: UK: +44 (0)

41 Further Reading 1) Manual of Dietetic Practice, 4 th edition, edited by Briony Thomas and Jacki Bishop 2) 3) 4) 5)

Rand E. Dankner, M.D. Jacqueline L. Reiss, M. D.

Rand E. Dankner, M.D. Jacqueline L. Reiss, M. D. Tips to Remember: Food allergy Up to 2 million, or 8%, of children, and 2% of adults in the United States are estimated to have food allergies. With a true food allergy, an individual's immune system will