Defining functional foods M. B. Roberfroid, Universite Catholique de louvain, Brussels 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 of dietary deficiency and the establishment of nutrition standards, dietary uidelines and food guides, to the promotion of a state of well-being and health and the reduction of the risk of disease 1.1.1 Nutrition: a science of the twentieth century Even though ' diet'and food are very old terms, probably as old as human beings, the term 'nutrition is rather modern, appearing for the first time in the nineteenth century. Nutrition is multidisciplinary as it integrates and applies broad and available knowledge (including basic science) about foods and/or nutrients and their effects on body physiology with the aim of improving the state of well-being and health During the twentieth century, essential nutrients have been discovered and nutrient standards, dietary guidelines and food guides established, mainly if not exclusively 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 of miscellaneous(mostly chronic)diseases has been recognised. These advances are reflected in Nutrient standards, the recommended daily allowances(RDAs)or nutrition es(rNis) which are the ay daily amounts of
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 of dietary deficiency and the establishment of nutrition standards, dietary guidelines and food guides, to the promotion of a state of well-being and health and the reduction of the risk of disease. 1.1.1 Nutrition: a science of the twentieth century1 Even though ‘diet’ and ‘food’ are very old terms, probably as old as human beings, the term ‘nutrition’ is rather modern, appearing for the first time in the nineteenth century. Nutrition is multidisciplinary as it integrates and applies broad and available knowledge (including basic science) about foods and/or nutrients and their effects on body physiology with the aim of improving the state of well-being and health. During the twentieth century, essential nutrients have been discovered and nutrient standards, dietary guidelines and food guides established, mainly if not exclusively with the aim of preventing deficiencies and supporting body growth, maintenance and development. More recently, in the last 30 years, recommendations have also been made that we should aim to avoid excessive consumption of some of these nutrients since their potential role in the etiology of miscellaneous (mostly chronic) diseases has been recognised.2 These advances are reflected in: • Nutrient standards,3 the recommended daily allowances (RDAs) or reference nutrition intakes (RNIs) which are the ‘average daily amounts of essential 1 Defining functional foods M.B. Roberfroid, Universite´ Catholique de Louvain, Brussels
10 Functional foods nutrients estimated on the basis of available scientific knowledge to be sufficiently high to meet the physiological needs of nearly all healthy persons Dietary guidelines, which are advice on consumption of foods or food components for which there is a related public health concern, mostly when RDAS or RNIs are not available. These are expressed in relation to total diet, often in qualitative terms (more/less/increased/reduced ..) based on consensus research findings relating diet and health Food guides, which are the translation of nutritional standards and dietary guidelines in terms of recommendations on daily food intake. These form conceptual framework for selecting the kinds and amounts of foods of various types that, together, provide a nutritionally satisfactory diet. They are based on nutrient standards, composition of foods, food intake patterns and factors niluenci ing food choice Through these developments, one of the major contributions of nutritional science in the twentieth century has been the concept of the balanced diet, an appropriate mixture of food items that provides, at least, the minimum requirements of nutrients and a few other food components needed to support growth and maintain body weight, to prevent the development of deficiency diseases and to reduce the risk of diseases associated with deleterious excesses,6 1.1.2 Nutrition: a science for the twenty-first century At the turn of the twenty-first century, the society of abundance, which characterises most of the industrialised world. faces new challenges from an uncontrollable increase in the costs of health care, an increase in life expectancy improved scientific knowledge and development of new technologies to major hanges 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 Optimum(optimised) nutrition will aim at maximising the physiological functions of each individual, in order to ensure both maximum well-being and health but, at the same time a minimum risk of disease throughout In other words, it will have to aim at maximising a healthy lifespan. At the same time, it will have to match an individual's unique biochemical needs with a tailored selection 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 Exponential increase of health-care costs Increase in life expectancy Consumer awareness of nutrition and health relationships Progress in food technology
nutrients estimated on the basis of available scientific knowledge to be sufficiently high to meet the physiological needs of nearly all healthy persons’. • Dietary guidelines,4 which are ‘advice on consumption of foods or food components for which there is a related public health concern’, mostly when RDAs or RNIs are not available. These are expressed in relation to total diet, often in qualitative terms (more/less/increased/reduced . . .), based on consensus research findings relating diet and health. • Food guides,5 which are ‘the translation of nutritional standards and dietary guidelines in terms of recommendations on daily food intake’. These form a conceptual framework for selecting the kinds and amounts of foods of various types that, together, provide a nutritionally satisfactory diet. They are based on nutrient standards, composition of foods, food intake patterns and factors influencing food choice. Through these developments, one of the major contributions of nutritional science in the twentieth century has been the concept of the balanced diet, ‘an appropriate mixture of food items that provides, at least, the minimum requirements of nutrients and a few other food components needed to support growth and maintain body weight, to prevent the development of deficiency diseases and to reduce the risk of diseases associated with deleterious excesses’. 6 1.1.2 Nutrition: a science for the twenty-first century At the turn of the twenty-first century, the society of abundance, which characterises most of the industrialised world, faces new challenges from an uncontrollable increase in the costs of health care, an increase in life expectancy, improved scientific knowledge and development of new technologies to major changes 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.7 Optimum (optimised) nutrition will aim at maximising the physiological functions of each individual, in order to ensure both maximum well-being and health but, at the same time, a minimum risk of disease throughout life. In other words, it will have to aim at maximising a healthy lifespan. At the same time, it will have to match an individual’s unique biochemical needs with a tailored selection 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 10 Functional foods
Defining functional foods 11 a better understanding of the interactions between genes and nutrition. These interactions include: polymorphism and interindividual variations in response to diet, dietary alteration and modulation of gene expression, and dietary effects on disease risk. These interactions play a role both in the modulation of specific physiological functions and/or pathophysiological processes by given food components, as well as in their metabolism by the body. They control the responsiveness of a particular individual to both the beneficial and deleterious ffects of their diet Even though a balanced diet remains a event deficiencies nd their associated diseases and to reduce the risk of the diseases associated with excess intake of some nutrients, optimum(optimised) nutrition will aim at establishing optimum(optimised) intake of as many food components as possible to support or promote well-being and health, and/or reduce the risk of diseases, 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 progress from improving life expectancy to improving life quality/wellness On the road to optimum(optimised) nutrition, which is an ambitious and long-term objective, functional food is, among others, a new, interesting and stimulating concept inasmuch as it is supported by sound and consensual scientific data get nerate by the recently developed functional food aimed at improving dietary guidelines by integrating new knowledge on the interactions between food components and body functions and/or pathological processes 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 as nutrients, 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, it would be unrealistic to try to produce such a definition for something as new and diverse as functional food functional food has thus to be understood as a concept. Moreover, if it is function driven rather than product driven, the concept is likely to be more universal and not too much influenced by local characteristics or cultural traditions 1.2.1 Functional food: an international overview Japan is the birthplace of the term ' functional food. Moreover, that country has been at the forefront of the development of functional foods since the early 1980s when systematic and large-scale research programmes were launched and
a better understanding of the interactions between genes and nutrition.8 These interactions include: polymorphism and interindividual variations in response to diet, dietary alteration and modulation of gene expression, and dietary effects on disease risk. These interactions play a role both in the modulation of specific physiological functions and/or pathophysiological processes by given food components, as well as in their metabolism by the body. They control the responsiveness of a particular individual to both the beneficial and deleterious effects of their diet. Even though a balanced diet remains a key objective to prevent deficiencies and their associated diseases and to reduce the risk of the diseases associated with excess intake of some nutrients, optimum (optimised) nutrition will aim at establishing optimum (optimised) intake of as many food components as possible to support or promote well-being and health, and/or reduce the risk of diseases, mainly for those that are diet-related. At the beginning of the twentyfirst century, the major challenge of the science of nutrition is thus to progress from improving life expectancy to improving life quality/wellness. On the road to optimum (optimised) nutrition, which is an ambitious and long-term objective, functional food is, among others, a new, interesting and stimulating concept inasmuch as it is supported by sound and consensual scientific data generated by the recently developed functional food science aimed at improving dietary guidelines by integrating new knowledge on the interactions between food components and body functions and/or pathological processes. 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 as nutrients, affecting a variety of body functions relevant to either a state of wellbeing 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, it would be unrealistic to try to produce such a definition for something as new and diverse as functional food. Functional food has thus to be understood as a concept. Moreover, if it is function driven rather than product driven, the concept is likely to be more universal and not too much influenced by local characteristics or cultural traditions.9 1.2.1 Functional food: an international overview Japan is the birthplace of the term ‘functional food’. 10 Moreover, that country has been at the forefront of the development of functional foods since the early 1980s when systematic and large-scale research programmes were launched and Defining functional foods 11
12 Functional foods funded by the Japanese government on systematic analysis and development of food functions, analysis of physiological regulation of function by food and analysis 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, the concept 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 for which specific health effects(claims)are allowed to be displayed, are included as one of the categories of foods described in the Nutrition Improvement Law as foods for special dietary use. According to the Japanese Ministry of Health and Welfare. FoShu are foods that are expected to have a specific health effect due to relevant constituents or foods from which allergens have been removed. and foods where the effect of such an addition or removal has been scientifically evaluated, and permission has been granted to make claims regarding the specific beneficial effects on health expected from their consumption Foods identified as FOSHU are required to provide evidence that the final food product, but not isolated individual component(s), is likely to exert a health or physiological effect when consumed as part of an ordinary diet. Moreover FOSHU products should be in the form of ordinary foods (i.e. not pills or In the meantime, but mainly in the 1990s, a variety of terms, more or less related to the Japanese FOSHU, has appeared worldwide. In addition to functional foods. these include more exotic terms such as nutraceuticals designer foods, f(ph )armafoods','medifoods',vitafoods', etc, but also the more traditional dietary supplements and fortified foods. According to Hillian these terms intend to describe food substances that provide medical or health benefits including the prevention and treatment of disease. As discussed in an editorial of the Lancet, these are "foods or food products marketed with the message of a benefit to healthand they 'sit in the murky territory between food and medicine For the editors of two other books entitled Functional Foods, these terms cover 'foods that can prevent or treat disease"or foods or isolated food ingredients that deliver specific nonnutritive physiological benefits hat may enhance health.For 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 broad sense 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 prevention and treatment of disease6 or'a product produced from foods but sold in powders, pills and other medicinal forms not generally associated with food and demonstrated to have physiological benefits or provide protection against chronic disease
funded by the Japanese government on systematic analysis and development of food functions, analysis of physiological regulation of function by food and analysis of functional foods and molecular design. As a result of a long decisionmaking 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, the concept 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 for which specific health effects (claims) are allowed to be displayed, are included as one of the categories of foods described in the Nutrition Improvement Law as foods for special dietary use. According to the Japanese Ministry of Health and Welfare, FOSHU are: • foods that are expected to have a specific health effect due to relevant constituents, or foods from which allergens have been removed, and • foods where the effect of such an addition or removal has been scientifically evaluated, and permission has been granted to make claims regarding the specific beneficial effects on health expected from their consumption. Foods identified as FOSHU are required to provide evidence that the final food product, but not isolated individual component(s), is likely to exert a health or physiological effect when consumed as part of an ordinary diet. Moreover, FOSHU products should be in the form of ordinary foods (i.e. not pills or capsules). In the meantime, but mainly in the 1990s, a variety of terms, more or less related to the Japanese FOSHU, has appeared worldwide. In addition to functional foods, these include more exotic terms such as ‘nutraceuticals’, ‘designer foods’, ‘f(ph)armafoods’, ‘medifoods’, ‘vitafoods’, etc., but also the more traditional ‘dietary supplements’ and ‘fortified foods’. According to Hillian11 these terms intend to describe ‘food substances that provide medical or health benefits including the prevention and treatment of disease’. As discussed in an editorial of the Lancet, 12 these are ‘foods or food products marketed with the message of a benefit to health’ and they ‘sit in the murky territory between food and medicine’. 13 For the editors of two other books entitled Functional Foods, these terms cover ‘foods that can prevent or treat disease’ 14 or ‘foods or isolated food ingredients that deliver specific nonnutritive physiological benefits that may enhance health’. 15 For 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 broad sense 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 prevention and treatment of disease’ 16 or ‘a product produced from foods but sold in powders, pills and other medicinal forms not generally associated with food and demonstrated to have physiological benefits or provide protection against chronic disease’. 17 12 Functional foods
Defining functional foods 13 Vitafoods are defined by the Ministry of Agriculture, Fisheries and Food MAFF)as foods and drinks to meet the needs of modern health conscious nsumers which enhance the bodily or mental quality of life, enhance the capacity 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 potential deterrent to health hazard Dietary supplements have, at least in the USA, a more elaborate definition which covers 'a product intended to supplement the diet and that bears or contains one or more of certain specified dietary ingredients(vitamins, minerals, herbs or other botanicals, amino-acids, a dietary supplement)to supplement 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 a conventional food but is not represented as a conventional.However, in france the definition is more restrictive, being a product to be ingested to complement the usual diet in order to make good any real or anticipated deficiencies in daily intake 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 nutrition foods or food products marketed with the message of the benefit to health veryday food transformed into a potential lifesaver by the addition of a magical ingredient to very elaborate definitions such as food and drink products derived from naturally occurring substances consumed as part of the daily diet and possessing particular physiological benefits when ingested food derived from naturally occurring substances that can and should be consumed as part of the daily diet and that serve to regulate or otherwise affect a particular body process when ingested food similar in appearance to conventional food, which is consumed as part of a usual diet and has demonstrated physiological benefit and/or reduces the risk of chronic disease beyond basic nutritional functions food that encompasses potentially helpful products including any modified food or food ingredient that may provide a health benefit beyond that of the traditional nutrient it contains food similar in appearance to conventional food that is intended to be consumed as part of a normal diet, but has been modified to subserve physiological roles beyond the provision of simple nutrient requirements Whatever definition is chosen, functional food appears as concept that deserves a category of its own, a category nutraceutical, f(ph)armafood, medifood, designer food or vitafood
• Vitafoods are defined by the Ministry of Agriculture, Fisheries and Food (MAFF) as ‘foods and drinks to meet the needs of modern health conscious consumers which enhance the bodily or mental quality of life, enhance the capacity 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 potential deterrent 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 or contains one or more of certain specified dietary ingredients (vitamins, minerals, herbs or other botanicals, amino-acids, a dietary supplement) to supplement 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 a conventional food but is not represented as a conventional’. 19 However, in France the definition is more restrictive, being ‘a product to be ingested to complement the usual diet in order to make good any real or anticipated deficiencies 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 a magical ingredient13 to very elaborate definitions such as: • food and drink products derived from naturally occurring substances consumed as part of the daily diet and possessing particular physiological benefits when ingested11 • food derived from naturally occurring substances that can and should be consumed as part of the daily diet and that serve to regulate or otherwise affect 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 the risk of chronic disease beyond basic nutritional functions17 • food that encompasses potentially helpful products including any modified food or food ingredient that may provide a health benefit beyond that of the traditional nutrient it contains23 • food similar in appearance to conventional food that is intended to be consumed as part of a normal diet, but has been modified to subserve physiological roles beyond the provision of simple nutrient requirements. Whatever definition is chosen, ‘functional food’ appears as a quite unique concept that deserves a category of its own, a category different from nutraceutical, f(ph)armafood, medifood, designer food or vitafood, and a Defining functional foods 13