Tài liệu Functional foods pdf

A probiotic can be defined as a live microbial food supplement whichbeneficially affects the host by improving its intestinal microbial balance.Probiotics are thought to have a range of

nutrition list:

Benders’ dictionary of nutrition and food technology Seventh edition (ISBN: 1 85573

475 3)

David A Bender and Arnold E Bender

The seventh edition provides succinct, authoritative definitions of over 5000 terms innutrition and food technology (an increase of 25% from the previous edition) Inaddition there is nutrient composition data for 287 foods

‘This valuable book continues to fulfil the purpose of explaining to specialists in other

fields the technical terms in nutrition and food processing.’ Chemistry and Industry.

Food labelling (ISBN: 1 85573 496 6)

Edited by J Ralph Blanchfield

Food labelling has become a complex and controversial area This collection draws onthe experience of key experts in their field to provide food manufacturers with aframework within which to plan labelling effectively It covers both the key legislationthey need to be aware of, and the issues they need to take account of in successfullabelling

Functional foods (ISBN: 1 56676 487 4)

G Mazza

This text brings together key research on the nature and physiological effects ofbiologically-active components of major plant foods It also reviews the majorprocesses for extraction, purification, concentration and formulation of functionalproducts, and the functional characteristics of end products

Phytochemicals as bioactive agents (ISBN: 1 56676 788 1)

W R Bidlack and M S Meskin

This book focuses on the mechanisms of action of phytochemicals identified asdisplaying bioactivity in the prevention of cancer, heart disease and other diseases, andthe prospects for developing functional foods containing these bioactive compounds.Details of these books and a complete list of Woodhead’s food science, technologyand nutrition titles can be obtained by:

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Functional foods

Concept to product

Edited by Glenn R Gibson and Christine M Williams

Abington Hall, Abington

First published 2000, Woodhead Publishing Limited and CRC Press LLC

ß 2000, Woodhead Publishing Limited

The authors have asserted their moral rights

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1945–2000

List of contributors xiii

List of abbreviations xv

Introduction 1 Part I General issues 1 Defining functional foods 9

M.B Roberfroid, Universite´ Catholiquie de Louvain, Brussels 1.1 Introduction 9

1.2 Functional foods: defining the concept 11

1.3 Functional food science 16

1.4 Communicating functional claims 19

1.5 Case studies 22

1.6 Food technology and its impact on functional food development 24

1.7 Future trends 25

1.8 References 25

2 EU legislation and functional foods: a case study 29

P Berry Ottaway, Consultant, Berry Ottaway and Associates Ltd, Hereford 2.1 Introduction 29

2.2 Product description 29

2.3 Product positioning in the European market 30

2.4 Product composition 30

Contents

2.5 Functional claims 36

2.6 Packaging 38

2.7 Labelling 39

2.8 Manufacture 40

2.9 References 40

3 US legislation and functional health claims 43

M.K Schmidl and T.P Labuza, University of Minnesota 3.1 Introduction 43

3.2 Definitions 44

3.3 Nutrient modification and specific nutrient claims 46

3.4 Disease-specific or disease-prevention (health) claims 47

3.5 The Food and Drug Administration Modernization Act 1997 55 3.6 Medical foods 56

3.7 The Dietary Supplement Health and Education Act 1994 57

3.8 The controversy over labeling 64

3.9 Advertising and the Federal Trade Commission 65

3.10 Future trends 66

3.11 Further reading 67

3.12 References 67

Part II Functional foods and health 4 Colonic functional foods 71

R.A Rastall (University of Reading), R Fuller (Russett House, Reading), H.R Gaskins (University of Illinois, Champaign, Urbana) and G.R Gibson (University of Reading) 4.1 Introduction 71

4.2 What are colonic functional foods? 72

4.3 How are colonic foods metabolised? 73

4.4 Probiotics 75

4.5 Prebiotics 77

4.6 Synbiotics 81

4.7 Health aspects of functional colonic foods 82

4.8 Host–microbe interaction 85

4.9 Conclusion 89

4.10 References 89

5 Coronary heart disease 97

J.A Lovegrove and K.G Jackson, University of Reading 5.1 Introduction 97

5.2 Coronary heart disease and risk factors 100

5.3 Relevant lipid particles 104

5.4 Diet and coronary heart disease: the evidence 111

5.5 Effects of probiotics on blood lipids: the evidence 118

5.6 The effects of prebiotics on coronary heart disease 124

5.7 The effects of synbiotics on coronary heart disease 130

5.8 Future trends 130

5.9 Sources of further information and advice 131

5.10 References 132

6 Anti-tumour properties 141

I.T Johnson, Institute of Food Research, Norwich 6.1 Introduction 141

6.2 The nature of tumour growth 143

6.3 Models of carcinogenesis 145

6.4 Diet and gene interactions 146

6.5 Mechanisms of action: nutrients 148

6.6 Mechanisms of action: phytochemicals 153

6.7 Mechanisms of action: other factors 156

6.8 Conclusion: the role of functional food 159

6.9 Future trends 160

6.10 Sources of further information and advice 160

6.11 References 161

7 Functional foods and acute infections: probiotics and gastrointestinal disorders 167

E Isolauri and S Salminen, University of Turku 7.1 Introduction 167

7.2 The background 168

7.3 Probiotics and the immune system 172

7.4 Probiotic functional foods and the treatment of gastrointestinal disorders 175

7.5 Future trends 176

7.6 Sources of further information and advice 177

7.7 References 177

Part III Developing functional food products 8 Maximising the functional benefits of plant foods 183

D.G Lindsay, Institute of Food Research, Norwich 8.1 Introduction 183

8.2 The concept of functionality 184

8.3 Functional effects deliverable by plants 185

8.4 Plant sources of functional compounds 187

8.5 The delivery of functional effects 188

8.6 Enhancing functional effects 188

8.7 Factors affecting the intake of functional compounds 192

8.8 Enhancing macronutrient quality 192

8.9 Enhancing micronutrient quality 197

8.10 The effects of food processing 202

8.11 Future trends: the work of NEODIET 204

8.12 References 205

9 Developing functional ingredients: a case study 209

A.-S Sandberg, Chalmers University of Technology, Gothenburg 9.1 Introduction: the nutritional properties of peas 209

9.2 Improving pea protein 212

9.3 Processing issues in improving pea protein 213

9.4 Adding improved protein to food products 215

9.5 Evaluating the functional and sensory properties of improved pea protein in food products 217

9.6 Future trends: the work of NUTRIPEA 221

9.7 Sources of further information and advice 224

9.8 References 228

10 Functional fats and spreads 233

E.A.M de Deckere and P.M Verschuren, Unilever Research, Vlaardingen 10.1 Introduction 233

10.2 Functional ingredients and chronic diseases: applications in fats and spreads 234

10.3 Fatty acids 234

10.4 Spreads containing fish oil 240

10.5 Modified fats and oils 241

10.6 Phytosterols 243

10.7 Antioxidants 245

10.8 Low (zero) fat spreads 247

10.9 Inulin 249

10.10 Calcium 249

10.11 Conclusions 250

10.12 References 250

11 Functional confectionery 259

E.F Pickford and N.J Jardine, Nestle´ Product Technology Centre, York 11.1 Introduction 259

11.2 Types of functional confectionery 261

11.3 The current market in functional confectionery 261

11.4 The development and manufacture of functional confectionery products 268

11.5 Marketing and retailing functional confectionery 278

11.6 Summary 284

11.7 References 285

12 Probiotic functional foods 287

T Mattila-Sandholm and M Saarela, VTT Biotechnology, Espoo 12.1 Introduction: the health benefits of probiotic foods 287

12.2 Selecting probiotic strains 292

12.3 Pilot testing in clinical human trials 297

12.4 Processing issues in developing probiotic foods 302

12.5 Future trends 303

12.6 Sources of further information and advice 305

12.7 References 306

13 Dietary fibre functional products 315

F Guillon (URPOI, Centre de Recherches INRA, Nantes), M Champ (UFDNH, Centre de Recherches INRA, Nantes), and J.-F Thibault (URPOI, Centre de Recherches INRA, Nantes) 13.1 Introduction 315

13.2 Defining dietary fibre 316

13.3 Sources of dietary fibre 321

13.4 Processing dietary fibre ingredients 329

13.5 Processing foods containing dietary fibre 337

13.6 The physiological effects of dietary fibre 340

13.7 Recommended intakes of dietary fibre 350

13.8 Conclusions and future trends 351

13.9 Bibliography 355

Index 365

Chapter 1

Professor Marcel Roberfroid

Universite´ Catholique de Louvain

Mr Peter Berry Ottaway

Berry Ottaway & Associates

Chapter 4

Professor Glenn R GibsonThe University of ReadingDepartment of Food Science &

Technology

PO Box 226WhiteknightsReading RG6 6APTel: +44 (0)118 931 8700Fax: +44 (0)118 931 0080E-mail: g.r.gibson@reading.ac.uk

Chapter 5

Drs Julie Lovegrove and Kim JacksonDepartment of Food Science & TechnologyUniversity of Reading

PO Box 226WhiteknightsReading RG6 6APTel: 0118 931 8700

Contributors

Fax: 0118 931 0080

E-mail: food@afnovell.reading.ac.uk

Chapter 6

Professor Ian Johnson

Institute of Food Research

Norwich Research Park

Institute of Food Research

Norwich Research Park

Professor Ann-Sofie Sandberg

Department of Food Science

Chalmers University of Technology

3133 At VlaardingenThe NetherlandsTel: +31 10 4606367Fax: +31 10 4605993E-mail: Emile-de.Deckere@unilever.com

Chapter 11

Dr Emma PickfordNestle´ Product Technology Centre

PO Box 204Haxby RoadYork YO91 1XXTel: +44 (0)1904 603194Fax: +44 (0)1904 604887E-mail: emma.pickford@rdyo.nestle.com

Chapter 12

Professor Tiina Mattila-SandholmVTT Biotechnology

Box 1500FIN-02044-VTTFinlandTel: +358 9 4565200Fax: + 358 9 455 2028E-mail: tiina.mattila-sandholm@vtt.fi

Chapter 13

Professor Fabienne GuillonURPOI-Micro-MacrostructureINRA Nantes

Rue de la Geraudiere BP 71 627 44 316Nantes Cedex 03

FranceTel: +33 (0) 2 40 67 50 38Fax: +33 (0) 2 40 67 50 06E-mail: guillon@nantes.inra.fr

AFLP amplified fragment length polymorphism

ALP atherogenic lipoprotein phenotype

AOAC American Organization of Agricultural ChemistsAPA Administrative Procedure Act 1946

BATF Bureau of Alcohol, Tobacco and Firearms

CARET carotene and retinol efficacy trial

CETP cholesterol ester transfer protein

CFSAN Center for Food Safety and Applied Nutrition

CFR Code of Federal Regulations

CPGM Compliance Policy Guides Manual

DSHEA Dietary Supplement Health and Education Act 1994ELISA enzyme-linked immunosorbant assay

ERH equilibrium relative humidity

FAIR Food and Agro-Industrial Research

FDAMA Food and Drug Administration Modernization Act 1997

Abbreviations

FFDCA Federal Food, Drug and Cosmetic Act 1938

FISH fluorescent in situ hybridisation

FOS fructo-oligosacccharides oligosaccharides

FOSHU food for specified health use

FSIS Food Safety and Inspection Service

FUFOSE Functional Food Science in Europe

GALT gut associated lymphoid tissue

GRAS generally recognized as safe

HACCP hazard analysis and critical control point

HDL high density lipoprotein

HMG-CoA hydroxy-methyl-glutaryl CoA

HPLC high performance liquid chromatography

IDL intermediate density lipoprotein

ILSI International Life Science Institute

IMO isomalto-oligosaccharide

LCAT lecithin cholesterol acyltransferase

MAFF Ministry of Agriculture, Fisheries and Food

MUFA monounsaturated fatty acid

NIDDM non insulin dependent diabetes mellitus

NLEA Nutrition Labeling and Education Act 1990

NSP non-starch polysaccharide

PER protein efficiency ratio

PUFA polyunsaturated fatty acid

RDA recommended daily allowance; recommended dietary

allowance (US)

RNI reference nutrition intake

ROS reactive oxidative species

SCFA short chain fatty acid

SDS-PAGE sodium dodecyl sulfate-polyacrylamid gel electrophoresis

TCM traditional Chinese medicine

USDA United States Department of Agriculture

VLDL very low density lipoprotein

Defining functional foods

What are functional foods? The complexities involved in definition are a keytheme in Chapter 1 of this book This suggests the following working definitionwhich seeks to isolate the significance of both ‘functional’ and ‘food’ in ourunderstanding of the term:

A food can be regarded as ‘functional’ if it is satisfactorily

demon-strated to affect beneficially one or more target functions in the body,beyond adequate nutrition, in a way that improves health and well-being

or reduces the risk of disease

This definition suggests that a product must remain a food to be included withinthe category On this basis a functional food can be:

Introduction

improve the capacity to resist disease and enhance health Functional foods areone of the outcomes of this.

The functional foods market

Functional foods first emerged in Japan in the early 1980s Estimates of thevalue of the functional foods market vary enormously, depending on how thecategory is defined Some estimates suggest the world market has grown fromUS$7–10 billion in 1995 to over US$15 billion in 2000, with annual growthrates averaging 10% Japan has traditionally accounted for around half of allfunctional food sales (an estimated US$3–4 billion in 1996), although thisproportion is decreasing as the European and US markets expand The USmarket was worth about US$8 billion in 1997 with growth at around 5% perannum Sales of functional foods in Europe in 1997 have been estimated atUS$1.7 billion, growing to around US$2 billion by 2000

There have been a number of important forces driving this growth Theseinclude:

• new research on the links between diet and the prevention of chronic disease

• ageing populations in many developed countries, and an increasing concernabout managing the health of this age group who are more prone to disease(and particularly such degenerative disorders as cancer, heart disease,osteoporosis, diabetes and stroke)

• growing pressure on public health spending, leading to a greater emphasis onprevention and more individual responsibility for health care provision

• increased health consciousness among consumers and concern about theirdietary intake

• improvements in food science and technology

• changes in the regulatory framework governing this area

Classifying functional foods

As a result of increasing market growth, there is a huge possible range offunctional foods These include:

• soft drinks such as energy and sports drinks

• cereal and baby foods

These functional foods offer varying types of benefit and act in differing ways.One way of categorising their mode of operation is as follows:

• vitamin and mineral fortification

• herbs and botanicals

Examples of products fortified with vitamins and minerals include fortified confectionery and fruit drinks, and calcium-enriched milk with folicacid Folic acid, for example, is documented as a vital nutrient in earlypregnancy that guards against spina bifida, while the importance of calcium hasbeen recognised in counteracting osteoporosis Given the prevalence ofosteoporosis among the increasing proportion of elderly people in developedcountries, improving calcium intake has been seen as particularly significant inthis sector of the functional foods market Research has concentrated not just onways of increasing levels of calcium intake but also in improving the efficiency

calcium-of calcium absorption

A number of ingredients are associated with inhibiting the absorption ofcholesterol which is thought to be a major factor in cardiovascular disease Thiscategory includes omega-3 fatty acids and plant sterols Examples of products inthis area include a margarine containing plant sterol fatty acid esters designed toreduce cholesterol absorption, and omega-3 enriched eggs produced by chickensfed a micoalgal feed ingredient

Dietary fibre comprises the non-digestible structural carbohydrates of plantcell walls and associated lignan Consumption of fibre has been linked to areduced risk of certain types of cancer, for example consumption of wheat branwhich has been linked to a reduced risk of colon cancer High-fibre productsinclude a whole-wheat pasta with three times the fibre of regular pasta

A probiotic can be defined as a live microbial food supplement whichbeneficially affects the host by improving its intestinal microbial balance.Probiotics are thought to have a range of potential health benefits, includingcholesterol-lowering, cancer chemopreventative and immune-enhancing effects.Probiotics are viewed currently as the world’s biggest functional food products.This sector of the functional foods market has been stimulated in recent years bythe development of prebiotics, short chain oligosaccharides which enhance thegrowth of beneficial bacteria already in the gut, and synbiotics which combinepro- and prebiotic characteristics The field of gut health is now an area ofintense research in functional food science

Cancerous and other mutations can occur as a result of oxidative damage toDNA caused by free radicals generated as a damaging side-effect of aerobicmetabolism Plant and animal cells defend themselves against these effects bydeploying so-called antioxidant compounds to trap or quench free radicals and

hence arrest their damaging reactions Antioxidants thus play a role in thebody’s defence against cardiovascular disease, certain (epithelial) cancers,visual impairments, arthritis and asthma Antioxidants include vitamin E,carotene, vitamin C and certain phytochemicals Functional products incorpor-ating antioxidant supplements include sports bars containing vitamins C and E

as well as a blend of several carotenoids (alpha- and gamma-carotene andlycopene)

Plant foods are rich in micronutrients, but they also contain an immensevariety of biologically active, non-nutritive secondary metabolites providingcolour, flavour and natural toxicity to pests and sometimes humans These

‘phytochemicals’ have been linked to reducing the risk of chronic diseases such

as cancer, osteoporosis and heart disease They include glucosinolates andphenolic compounds like flavonoids which are very effective antioxidants.Examples of products including phytochemicals are children’s confectionerycontaining concentrates of vegetables such as broccoli, Brussels sprouts,cabbage and carrots

More recently, herbs and botanicals such as ginkgo, ginseng and guaranahave been linked to improved physical and mental performance These may lead

to a new generation of ‘performance’ functional foods including these and othercomponents such as creatin, caffeine and tryptophane Products in this areainclude beverages, chewing gum and sports bars One product that combines arange of functional claims is a fruit juice designed for the sports marketcontaining carnitine, an amino acid to assist the body in producing energy and inlowering cholesterol, calcium to improve skeletal strength and chromiumpicolinate to help build lean muscle mass

Key issues in functional foods: the structure of this book

The functional food industry and interested scientists face a number of keychallenges:

• agreeing standards for the validation of claims about the health benefits offunctional foods

• ensuring a regulatory framework which balances consumer protection in theway that functional claims are validated and communicated with the freedomfor the industry to develop functional products profitably and effectively

• identifying and screening potential functional ingredients for development

• assessing the technological and commercial feasibility of new product ideas

• building in appropriate systems for validating product safety and functionalbenefits, for example through clinical human trials

• scaling up for commercial production

This collection of chapters addresses this range of issues Chapter 1 looks at thekey issues of definition and an appropriate methodology for substantiatingfunctional claims It outlines the idea of identifying ‘markers’ in demonstrating

the impact of a functional ingredient on a target function in the body, and alsoaddresses the problem of how the results of such verification procedures can becommunicated effectively to consumers Chapters 2 and 3 then consider thecurrent regulatory framework in the EU and the US respectively, includingcurrent controls on making health claims for functional products.

Part II of this book consists of a series of chapters summarising the currentstate of research on the links between functional foods and health Anunderstanding of this is obviously critical to the claims that manufacturers canmake about functional products Chapter 4 looks at colonic functional foods:probiotics, prebiotics and synbiotics It describes current research on their mode

of operation and health benefits Chapter 5 considers the contribution offunctional foods to the prevention of coronary heart disease, identifying the role

of dietary factors and considering the impact of antioxidants, probiotics,prebiotics and synbiotics In Chapter 6, the role of functional foods in preventingcancer is discussed, looking particularly at antioxidants, phytochemicals anddietary fibre Finally, Chapter 7 looks at the effects of functional foods on acutedisorders, assessing the role of probiotics in enhancing the immune system and

in prevention and treatment of gastrointestinal disorders

In Part III the focus shifts to product development issues Chapter 8 considersthe range of plant sources of functional compounds and the impact of processing

on these compounds It also discusses methods of enhancing functionalproperties such as genetic modification, and includes case studies illustratingimprovements to plant macronutrient and micronutrient content Building onthis, Chapter 9 provides a case study of the identification of a functional plantingredient, preparation and processing issues, applications in food andmeasurement

Two chapters assess the issue of selecting a functional ingredient Chapter 10considers the research and processing issues involved in identifying a targetfunctional ingredient from the range on offer, concentrating on functional fatsand spreads In Chapter 11, the functional confectionery market is used toanalyse the process of product development from market analysis through toformulation, testing and marketing The final chapters look at processing issues.Chapter 12 discusses probiotic foods and such issues as selecting strains, pilottesting in clinical trials and commercial production Chapter 13 looks at dietaryfibre functional foods, discussing sources, processing and measurement offunctional properties

Part I

General issues

1.1 Introduction

To understand functional food it is first necessary to understand how the science

of nutrition itself has changed Nutrition has progressed from the prevention ofdietary deficiency and the establishment of nutrition standards, dietaryguidelines and food guides, to the promotion of a state of well-being andhealth and the reduction of the risk of disease

1.1.1 Nutrition: a science of the twentieth century 1

Even though ‘diet’ and ‘food’ are very old terms, probably as old as humanbeings, the term ‘nutrition’ is rather modern, appearing for the first time in thenineteenth century Nutrition is multidisciplinary as it integrates and appliesbroad and available knowledge (including basic science) about foods and/ornutrients and their effects on body physiology with the aim of improving thestate of well-being and health

During the twentieth century, essential nutrients have been discovered andnutrient standards, dietary guidelines and food guides established, mainly if notexclusively with the aim of preventing deficiencies and supporting body growth,maintenance and development More recently, in the last 30 years, recommen-dations have also been made that we should aim to avoid excessive consumption

of some of these nutrients since their potential role in the etiology ofmiscellaneous (mostly chronic) diseases has been recognised.2These advancesare reflected in:

• Nutrient standards,3 the recommended daily allowances (RDAs) or referencenutrition intakes (RNIs) which are the ‘average daily amounts of essential

1

Defining functional foods

M.B Roberfroid, Universite´ Catholique de Louvain, Brussels

nutrients estimated on the basis of available scientific knowledge to besufficiently high to meet the physiological needs of nearly all healthy persons’.

• Dietary guidelines,4 which are ‘advice on consumption of foods or foodcomponents for which there is a related public health concern’, mostly whenRDAs or RNIs are not available These are expressed in relation to total diet,often in qualitative terms (more/less/increased/reduced ), based onconsensus research findings relating diet and health

• Food guides,5which are ‘the translation of nutritional standards and dietaryguidelines in terms of recommendations on daily food intake’ These form aconceptual framework for selecting the kinds and amounts of foods of varioustypes that, together, provide a nutritionally satisfactory diet They are based

on nutrient standards, composition of foods, food intake patterns and factorsinfluencing food choice

Through these developments, one of the major contributions of nutritionalscience in the twentieth century has been the concept of the balanced diet, ‘anappropriate mixture of food items that provides, at least, the minimumrequirements of nutrients and a few other food components needed to supportgrowth and maintain body weight, to prevent the development of deficiencydiseases and to reduce the risk of diseases associated with deleteriousexcesses’.6

1.1.2 Nutrition: a science for the twenty-first century

At the turn of the twenty-first century, the society of abundance, whichcharacterises most of the industrialised world, faces new challenges from anuncontrollable increase in the costs of health care, an increase in life expectancy,improved scientific knowledge and development of new technologies to majorchanges in lifestyles (Table 1.1) Nutrition has to adapt to these new challenges

As a consequence, nutrition as a science will, in addition to keeping an emphasis

on balanced diet, develop the concept of optimum (optimised) nutrition.7Optimum (optimised) nutrition will aim at maximising the physiologicalfunctions of each individual, in order to ensure both maximum well-being andhealth but, at the same time, a minimum risk of disease throughout life In otherwords, it will have to aim at maximising a healthy lifespan At the same time, itwill have to match an individual’s unique biochemical needs with a tailoredselection of nutrient intakes for that individual Such a selection will be based on

Table 1.1 The challenges for nutrition at the beginning of the twenty-first century

• Application of new scientific knowledge in nutrition

• Improved scientific knowledge on diet–disease relationships

• Exponential increase of health-care costs

• Increase in life expectancy

• Consumer awareness of nutrition and health relationships

• Progress in food technology

a better understanding of the interactions between genes and nutrition.8Theseinteractions include: polymorphism and interindividual variations in response todiet, dietary alteration and modulation of gene expression, and dietary effects ondisease risk These interactions play a role both in the modulation of specificphysiological functions and/or pathophysiological processes by given foodcomponents, as well as in their metabolism by the body They control theresponsiveness of a particular individual to both the beneficial and deleteriouseffects of their diet.

Even though a balanced diet remains a key objective to prevent deficienciesand their associated diseases and to reduce the risk of the diseases associatedwith excess intake of some nutrients, optimum (optimised) nutrition will aim atestablishing optimum (optimised) intake of as many food components aspossible to support or promote well-being and health, and/or reduce the risk ofdiseases, mainly for those that are diet-related At the beginning of the twenty-first century, the major challenge of the science of nutrition is thus to progressfrom improving life expectancy to improving life quality/wellness

On the road to optimum (optimised) nutrition, which is an ambitious andlong-term objective, functional food is, among others, a new, interesting andstimulating concept inasmuch as it is supported by sound and consensualscientific data generated by the recently developed functional food scienceaimed at improving dietary guidelines by integrating new knowledge on theinteractions between food components and body functions and/or pathologicalprocesses

1.2 Functional foods: defining the concept

Functional food cannot be a single well-defined/well-characterisable entity.Indeed, a wide variety of food products are or will, in the future, be characterised

as functional food with a variety of components, some of them classified asnutrients, affecting a variety of body functions relevant to either a state of well-being and health and/or to the reduction in risk of a disease Thus no simple,universally accepted definition of functional food exists Especially in Europe,where even the common term ‘dietary fibre’ has no consensual definition, itwould be unrealistic to try to produce such a definition for something as new anddiverse as functional food Functional food has thus to be understood as aconcept Moreover, if it is function driven rather than product driven, theconcept is likely to be more universal and not too much influenced by localcharacteristics or cultural traditions.9

1.2.1 Functional food: an international overview

Japan is the birthplace of the term ‘functional food’.10Moreover, that countryhas been at the forefront of the development of functional foods since the early1980s when systematic and large-scale research programmes were launched and

funded by the Japanese government on systematic analysis and development offood functions, analysis of physiological regulation of function by food andanalysis of functional foods and molecular design As a result of a long decision-making process to establish a category of foods for potential enhancing benefits

as part of a national effort to reduce the escalating cost of health care, theconcept of foods for specified health use (FOSHU) was established in 1991.These foods, which are intended to be used to improve people’s health and forwhich specific health effects (claims) are allowed to be displayed, are included

as one of the categories of foods described in the Nutrition Improvement Law asfoods for special dietary use According to the Japanese Ministry of Health andWelfare, FOSHU are:

• foods that are expected to have a specific health effect due to relevantconstituents, or foods from which allergens have been removed, and

• foods where the effect of such an addition or removal has been scientificallyevaluated, and permission has been granted to make claims regarding thespecific beneficial effects on health expected from their consumption.Foods identified as FOSHU are required to provide evidence that the final foodproduct, but not isolated individual component(s), is likely to exert a health orphysiological effect when consumed as part of an ordinary diet Moreover,FOSHU products should be in the form of ordinary foods (i.e not pills orcapsules)

In the meantime, but mainly in the 1990s, a variety of terms, more or lessrelated to the Japanese FOSHU, has appeared worldwide In addition tofunctional foods, these include more exotic terms such as ‘nutraceuticals’,

‘designer foods’, ‘f(ph)armafoods’, ‘medifoods’, ‘vitafoods’, etc., but also themore traditional ‘dietary supplements’ and ‘fortified foods’ According toHillian11these terms intend to describe ‘food substances that provide medical orhealth benefits including the prevention and treatment of disease’ As discussed

in an editorial of the Lancet,12these are ‘foods or food products marketed withthe message of a benefit to health’ and they ‘sit in the murky territory betweenfood and medicine’.13 For the editors of two other books entitled Functional Foods, these terms cover ‘foods that can prevent or treat disease’14or ‘foods orisolated food ingredients that deliver specific nonnutritive physiological benefitsthat may enhance health’.15For these authors, these terms are interchangeable.But it appears that these terms either describe quite different entities that cannot

be covered by a single heading or are formulated in such a general and broadsense that they lose specificity and become too vague to be really useful

• Nutraceuticals have been described as ‘any substance that is a food or part of

a food that provides medical and/or health benefits, including the preventionand treatment of disease’16 or ‘a product produced from foods but sold inpowders, pills and other medicinal forms not generally associated with foodand demonstrated to have physiological benefits or provide protection againstchronic disease’.17

• Vitafoods are defined by the Ministry of Agriculture, Fisheries and Food

(MAFF) as ‘foods and drinks to meet the needs of modern health consciousconsumers which enhance the bodily or mental quality of life, enhance thecapacity to endure or flourish or to recover from strenuous exercise or illness.They may also increase the healthy status of the consumer or act as potentialdeterrent to health hazard’.18

• Dietary supplements have, at least in the USA, a more elaborate definition

which covers ‘a product intended to supplement the diet and that bears orcontains one or more of certain specified dietary ingredients (vitamins,minerals, herbs or other botanicals, amino-acids, a dietary supplement) tosupplement the diet by increasing total dietary intake, a concentrate,metabolite, constituent, extract or combination It is a tablet, capsule,powder, softgel, gelcap or liquid droplet or some other form that can be aconventional food but is not represented as a conventional’.19 However, inFrance the definition is more restrictive, being ‘a product to be ingested tocomplement the usual diet in order to make good any real or anticipateddeficiencies in daily intake’.20

Functional food has as many definitions as the number of authors referring to it.These definitions go from simple statements such as:

• foods that may provide health benefits beyond basic nutrition21

• foods or food products marketed with the message of the benefit to health12

• everyday food transformed into a potential lifesaver by the addition of amagical ingredient13

to very elaborate definitions such as:

• food and drink products derived from naturally occurring substancesconsumed as part of the daily diet and possessing particular physiologicalbenefits when ingested11

• food derived from naturally occurring substances that can and should beconsumed as part of the daily diet and that serve to regulate or otherwiseaffect a particular body process when ingested22

• food similar in appearance to conventional food, which is consumed as part

of a usual diet and has demonstrated physiological benefit and/or reduces therisk of chronic disease beyond basic nutritional functions17

• food that encompasses potentially helpful products including any modifiedfood or food ingredient that may provide a health benefit beyond that of thetraditional nutrient it contains23

• food similar in appearance to conventional food that is intended to beconsumed as part of a normal diet, but has been modified to subservephysiological roles beyond the provision of simple nutrient requirements.Whatever definition is chosen, ‘functional food’ appears as a quite uniqueconcept that deserves a category of its own, a category different fromnutraceutical, f(ph)armafood, medifood, designer food or vitafood, and a

category that does not include dietary supplement It is also a concept thatbelongs to nutrition and not to pharmacology Functional foods are and must befoods, not drugs, as they have no therapeutic effects Moreover their roleregarding disease will, in most cases, be in reducing the risk of disease ratherthan preventing it.

1.2.2 Functional food: a European consensus 9, 24, 25

The unique features of functional food are:

• being a conventional or everyday food

• to be consumed as part of the normal/usual diet

• composed of naturally occurring (as opposed to synthetic) componentsperhaps in unnatural concentration or present in foods that would notnormally supply them

• having a positive effect on target function(s) beyond nutritive value/basicnutrition

• may enhance well-being and health and/or reduce the risk of disease orprovide health benefits so as to improve the quality of life including physical,psychological and behavioural performances

• have authorised and scientifically based claims

It is in that general context that the European Commission’s Concerted Action

on Functional Food Science in Europe (FUFOSE), which actively involved alarge number of the most prominent European experts in nutrition and relatedsciences, has been coordinated by the International Life Science Institute – ILSIEurope It developed in early 1996 to reach a European Consensus on ‘ScientificConcepts of Functional Foods’ in 1998.9 To reach that final objective, threemajor steps were undertaken:

1 Critical assessment of the science base required to provide evidence thatspecific nutrients and food components positively affect target functions inthe body

2 Examination of the available science from a function-driven perspectiverather than a product-driven one

3 Elaboration of a consensus on targeted modifications of food and foodconstituents, and options for their applications.24

In that context, ‘target function’ refers to genomic, biochemical, physiological,psychological or behavioural functions that are relevant to the maintenance of astate of well-being and health or to the reduction of the risk of a disease.Modulation of these functions should be quantitatively evaluated by measuringchange in serum or other body fluids of the concentration of a metabolite, aspecific protein or a hormone, change in the activity of enzymes, change inphysiological parameters (e.g blood pressure, gastrointestinal transit time, etc.),change in physical or intellectual performances, and so on

The major deliverables of that Concerted Action are three publications:

1 Functional Food Science in Europe reviews the published literature to

define the state of the art with respect to specific body systems, themethodologies to characterise and quantify specific related functions, thenutritional options modulating these functions, the safety implicationsrelated to these nutritional options, the role of food technology in nutritionaland safety aspects and the science base required for providing evidence thatspecific nutrients positively affect function.24

2 Technological Aspects of Functional Food Science reviews the impact of

processing, the importance of the source of materials to prepared foodproducts, processing options to modulate functionality, safety implications

of materials and processes, and process monitoring of functions.25

3 Scientific Concepts of Functional Foods in Europe: a consensus that

proposes, for the first time, a consensual framework for the development offunctional foods and for the elaboration of a scientific basis for claims.9

As already indicated above, because functional food is a concept rather than awell-defined group of food products, that consensus document proposes aworking definition:

A food can be regarded as functional if it is satisfactorily demonstrated

to affect beneficially one or more target functions in the body, beyondadequate nutritional effects, in a way that is relevant to either improvedstage of health and well-being and/or reduction of risk of disease Afunctional food must remain food and it must demonstrate its effects inamounts that can normally be expected to be consumed in the diet: it isnot a pill or a capsule, but part of the normal food pattern.9

The main aspects of this working definition are:

• the food nature of functional food that is not a pill, a capsule or any form ofdietary supplement

• the demonstration of the effects to the satisfaction of the scientificcommunity

• the beneficial effects on body functions, beyond adequate nutritional effects,that are relevant to improved state of health and well-being and/or reduction

of risk (not prevention) of disease

• the consumption as part of a normal food pattern

The definition encompasses all main features of functional foods identifiedabove; it is aimed at stimulating research and development in the field ofnutrition so as to contribute adequately to the scientific knowledge that will berequired to define optimum (optimised) nutrition by elaborating new dietaryguidelines However, it should be emphasised that a functional food will notnecessarily be functional for all members of the population, and that matchingindividual biochemical needs with selected food component intakes may become

a key task as we progress in our understanding of the interactions between genesand diet.8From a practical point of view, a functional food can be:

• a natural food

• a food to which a component has been added

• a food from which a component has been removed

• a food where the nature of one or more components has been modified

• a food in which the bioavailability of one or more components has beenmodified, or

• any combination of these possibilities

1.3 Functional food science

Being foods, functional foods need to be safe according to all criteria defined incurrent food regulations But in many cases, new concepts and new procedureswill need to be developed and validated to assess functional food risks InEurope, some, but certainly not all, functional foods will be classified as ‘novelfoods’ and consequently will require the decision tree assessment regardingsafety that is described in the EU Novel Food Regulation.26

However, it must be emphasised that this regulation does not concern thenutritional properties or the physiological effects of these novel foods It isstrictly a safety regulation The requirement for safety is a prerequisite to anyfunctional food development Indeed, the risk versus benefit concept, which isfamiliar to pharmacologists developing new drugs, does not apply to functionalfoods except perhaps in very specific conditions for disease risk reduction whenthe scientific evidence is particularly strong As described in the Europeanconsensus document:9

The design and development of functional foods is a key issue, as well

as a scientific challenge, which should rely on basic scientific edge relevant to target functions and their possible modulation by foodcomponents Functional foods themselves are not universal and a food-based approach would have to be influenced by local considerations Incontrast, a science-based approach to functional food is universal The function-driven approach has the science base as its foundation – inorder to gain a broader understanding of the interactions between dietand health Emphasis is then put on the importance of the effects offood components on well-identified and well-characterized target func-tions in the body that are relevant to well-being and health issues, ratherthan, solely, on reduction of disease risk

knowl-By reference to the new concepts in nutrition outlined above, it is the role of

Functional Food Science to stimulate research and development of functional

foods (see Fig 1.1)

By reference to basic knowledge in nutrition and related biological sciences,such a development requires the identification and, at least partly, anunderstanding of the mechanism(s) by which a potential functional food orfunctional food component can modulate the target function(s) that is/are

recognised or proven to be relevant to the state of well-being and health, and/orthe reduction of a disease risk Epidemiological data demonstrating astatistically validated and biologically relevant relationship between the intake

of specific food components and a particular health benefit will, if available, bevery useful The conclusion of that first step will be the demonstration of afunctional effect that should serve to formulate hypotheses to be tested in a newgeneration of human nutrition studies aimed to show that relevant (in terms ofdose, frequency, duration, etc.) intake of the specified food will be associatedwith improvements in one or more target functions, either directly or indirectly

in terms of a valid marker of an improved state of well-being and health and/orreduced disease risk If well supported by strong scientific evidence, theconclusion could be a recommendation for improved or new dietary guidelines.The new-generation human nutrition studies should be hypothesis driven but,

in many cases, they will differ quite substantially from what is classicallyreferred to as clinical studies.The main differences are that nutrition studies aim

at testing the effect of a food as part of the ordinary diet; they may concern thegeneral population or generally large, at-risk target groups; they are notdiagnostic; or symptom based; and they are not planned to evaluate a risk versusbenefit approach Most of these studies will rely on change(s) in validated/relevant markers to demonstrate a positive modulation of target functions after(long-term) consumption of the potential functional food A (double) blind type

of design based on parallel groups rather than crossing-over will generally beappropriate Data from these studies should be collected and handled according

to good standards for data management, and data analysis should provestatistical as well as biological significance Finally, the long-term consequences

of interaction(s) between functional foods and body function(s) will have to becarefully monitored

1.3.1 Markers: key to the development of functional foods

The development of functional foods will, in most cases, rely on measurements

of ‘markers’ These markers need to be identified and validated for their

Food Identification

Mechanism Function

Claim

Functional effect Hypothesis-driven human nutrition studies

Enhanced function Disease risk reduction

Fig 1.1 The strategy for functional food development

predictive value of potential benefits to a target function or the risk of aparticular disease Markers of correlated events are ‘indicators’ whereas markersrepresenting an event directly involved in the process are ‘factors’.9 Whenrelated to the risk of disease, indicators and even factors might, in someinstances, be equivalent to ‘surrogate markers’ defined as a biologicalobservation, result or index that predicts the development of chronic disease.27The more that is known about the mechanisms leading to health outcomes, themore refined will be the identification of the markers and their appreciation Themarkers should be feasible, valid, reproducible, sensitive and specific They can

be biochemical, physiological, behavioural or psychological in nature However,dynamic responses might be as useful as, or more useful than, static or singlepoint measurements In many cases, a battery of markers might be needed inorder to create a decision tree from multiple tests (see Fig 1.2)

These markers, most of which still need to be identified and validated, willrelate to:

• Exposure to the food component under study by measuring serum, faecal,urine or tissue level of the food component itself or its metabolite(s), or theconcentration of an endogenous molecule that is directly influenced by theconsumption of the food component

• Target function(s) or biological response such as change in serum or otherbody fluids of the concentration of a metabolite, a specific protein, anenzyme, a hormone, etc

These first two markers are either indicators or factors

• An appropriate endpoint of an improved state of well-being and health and/orreduction of a disease risk Such a marker is likely to be a factor rather than

biological response

Markers of exposure

Markers of intermediate endpoint

Improved state

of health and well-being

Reduced risk

of disease or

Fig 1.2 Markers for functional food development

To further develop these markers, a state-of-the-art literature review will benecessary to identify, define and characterise potential markers Furthermore,the basic scientific knowledge underpinning these markers will be evaluated.The next step will include assessment of their relevance to physiologicalfunction, to well-being and health and eventually to disease risk A validationwill then be necessary both for the methodology and biological relevance.Finally, classification as indicator or factor will be made and potential dietarymodulations demonstrated New techniques such as those used by molecular andcellular biologists will be useful in identifying target groups who could benefitfrom the consumption of specific functional foods.

1.4 Communicating functional claims

1.4.1 A communication challenge

As stated in the European consensus on scientific concepts of functional foods:9

As the relationship between nutrition and health gains public acceptanceand as the market for functional foods grows, the question of how tocommunicate the specific advantages of such foods becomes increas-ingly important Communication of health benefits to the public,

through intermediates such as health professionals, educators, the mediaand the food industry, is an essential element in improving public healthand in the development of functional foods Its importance also lies inavoiding problems associated with consumer confusion about healthmessages Of all the different forms of communication, those concerningclaims – made either directly as a statement on the label or package offood products, or indirectly through secondary supporting information –remain an area of extensive discussion

It is also the opinion of C.B Hudson that ‘the links between nutrition scienceand food product development will flow through to consumers only if therequired communication vehicles are put in place’.28 However, the commu-nication of health benefits and other physiological effects of functional foodsremains a major challenge because:

• science should remain the driving force;

• messages – claims – must be based on sound, objective and appropriateevidence; and

• evidence must be consistent, able to meet established scientific standards andplausible

Moreover, communication in nutrition generally comes from multiple sourcesthat are sometimes contradictory, creating an impression of chaos And chaoticinformation often generates ignorance and easily becomes misinformation (seeFig 1.3)

1.4.2 The scientific challenge

Regarding functional foods, claims associated with specific food products arethe preferable means of communicating to consumers In application of thefundamental principle, any claim must be true and not misleading; it must bescientifically valid, unambiguous and clear to the consumer However, thesebasic principles should be safeguarded without becoming a disincentive to theproduction of functional foods or to their acceptance by consumers Even though

a general definition of ‘claim’ is widely accepted in the field of nutrition as ‘anyrepresentation, which states, suggests or implies that a food has certaincharacteristics relating to its origin, nutritional properties or any otherquality’,29 one of the difficulties in communicating the benefits of functionalfoods is that distinct types of claims exist, and that in particular the term ‘healthclaims’, which is traditionally used to communicate the benefits of foods, isdefined differently in different parts of the world

Seeking clarity, Codex Alimentarius29 has recently classified and definedfour different categories of claims, but excluding the term ‘health claim’:

1 Relate to dietary guidelines

2 Relate to nutrient content

3 Are comparative (reduced, less, more )

4 Describe nutrient function (contains , that contributes to the development

Chaotic information?

Public authorities

Consumer organisations Media

scientific classification of markers (indicators and/or factors) for target functionsand on the effects on these markers If such an effect, which goes beyond whatcould be expected from the established role of diet in growth, development andother normal functions in the body, concerns a target function or a biologicalactivity without direct reference to a particular disease or pathological process,

claim will be made for an enhanced function But, if the benefit is clearly a

reduction of the risk of a disease or pathological process, claims will be made for

disease risk reduction These two types of claims, which are specific for functional foods, are the type A and type B claims respectively as they are

described in the European consensus on scientific concepts of functional foods.9The type A claim is similar to the ‘structure/function claim’, whereas the type Bclaim can be regarded as equivalent to ‘health claim’ in the USA respectively.The type B claim also corresponds to ‘health claim’ in Sweden.30 In its lastproposed draft recommendations for the use of health claims, CodexAlimentarius has included type A and type B claims and defined them as:31

• Type A or claims that concern specific beneficial effects of the consumption

of foods and their constituents on physiological or psychological functions orbiological activities but do not include nutrient function claims Such claimsrelate to a positive contribution to health or a condition linked to health, to theimprovement of a function or to modifying or preserving health

• Type B or ‘risk of disease reduction claims’ that concern the reduction of adisease risk related to the consumption of a food or a food constituent in thecontext of the daily diet that might help reduce the risk of a specific disease

• biological observations,

• epidemiological data, and

• intervention studies, mostly based on markers

For any given specific food product, supporting evidence for enhanced function

or reduction of disease risk might not be available or even not necessary from allthree areas.9All supporting evidence should, however, be: