Download v9.s1 - Asia Pacific Journal of Clinical Nutrition

October 2000 - Volume 9 Issue s1
Original Articles
S1
The Garden of Eden: Implications for cardiovascular disease prevention
David JA. Jenkins, AL Jenkins, CWC Kendall, V Vuksan,
E Vidgen
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S1 - October 2000
The Garden of Eden: Implications for cardiovascular disease prevention
DAVID JA. JENKINS, AL JENKINS, CWC KENDALL, V VUKSAN AND E VIDGEN
Creationists and evolutionists acknowledge that the human diet has passed through at
least four phases. The original plant food-based diet; a second phase of increasing meat
consumption; a third phase of agricultural dependence on starchy foods; and, finally, the
supermarket high-saturated fat, low-fibre phase with minimal energy expenditure. Our
aim is to define the value of the original or 'Garden of Eden' diet and to speculate on
which components should be retained in the modern supermarket diet. The original plantbased diet would have been high in vegetable proteins, plant sterols, dietary fibre and
antioxidants, and low in saturated fats with no trans fatty acids. This diet would increase
fecal cholesterol losses from the body as bile acids and neutral sterols, while providing
little stimulus to cholesterol synthesis. To replace the bile acid losses we would have
adapted to a relatively high capacity for cholesterol synthesis. Now, in the high-saturated
fat, low-fibre supermarket age, this may be a disadvantage and predisposes consumers to
high serum cholesterol and increased risk of cardiovascular disease. We believe part of
the solution is a return to the plant-based 'Garden of Eden' diet combined with physical
activity. A lipid-lowering portfolio containing vegetable proteins, especially soy, plant
sterols and high fibre intakes combined with low saturated and trans fatty acids and
cholesterol, would go a long way to reducing serum lipids and coronary heart disease risk
seen in the modern Western diet.
S4
Evidence-based nutrition
DIMITRIOS TRICHOPOULOS, PAGONA LAGIOU,
ANTONIA TRICHOPOULOU
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S4 - October 2000
Evidence-based nutrition
Dimitrios TrichopoulosMD1,2, Pagona LagiouMD1,2 and Antonia TrichopoulouMD2
What are the objectives of an ideal diet? Are they to prolong life or maximize quality
adjusted life expectancy? Does this focus on individuals or on the population at large,
taking equity and resources into account? What about externalities that should take into
account cultural heritage, protection of the environment and macroeconomic
considerations? Few people have the experience, expertise and knowledge to adequately
address these questions. It is only feasible to argue that there are two approaches in order
to establish the proper diet, with the limited objective of longevity. Contrary to the
assertions of several influential groups, there is no such thing as a 'positive health', and
longevity can only be defined as the inverse of mortality from all causes. The crucial
questions are: do we need to study the proper diet to reduce incidence of and mortality
from particular common diseases and then find the common elements in these various
diets in order to construct de novo the ideal diet (bottom up approach)? Alternatively, is it
better to harvest the experience of various cultures whose diets appear to protect against
premature morbidity and mortality (top down approach)? The first approach would rely
on associations between food groups, foods and nutrients on the one hand and the
incidence of specific diseases on the other, whereas the second would evaluate and
quantify the effects of 'natural' diets on longevity. The first approach has been largely
followed by mainstream nutritional epidemiologists, whereas the second has been
advocated by a few international experts.
S10
Your mother was right: Eat your vegetables
JOHN D POTTER
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S10 - October 2000
Your mother was right: Eat your vegetables
John D Potter, MBBS, PhD
A lower risk of cancer at many different sites is seen in association with higher intakes of
vegetables and fruit. There are many biologically plausible reasons for this potentially
protective association. It is argued that increasing intake of plant foods to 400-800 g/day
is a public health strategy of considerable importance for individuals and communities
worldwide.
S13
Soy and other legumes: 'Bean' around a long time but are they the
'superfoods' of the millennium and what are the safety issues for their
constituent phytoestrogens?
KENNETH DR SETCHELL, SUE RADD
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S13 - October 2000
Soy and other legumes: 'Bean' around a long time but are they the 'superfoods' of the millennium and what
are the safety issues for their constituent phytoestrogens?
Kenneth Dr SetchellPhD1 and Sue RaddBSc, Grad Dip Diet2
The recognition that legumes and, in particular, soybeans provide not only an excellent
source of vegetable protein but also contain appreciable amounts of a number of
phytoprotectants has increased general awareness of their potential nutritional and health
properties. Since the discovery that soybeans are one of the richest dietary sources of
bioavailable phytoestrogens, this legume has been elevated to the forefront of clinical
nutritional research. These natural 'selective oestrogen receptor modulators' have been
shown to be bioactive. The recent approval by the Food and Drug Administration in the
United States for a health claim for soy protein reducing risk for heart disease by its
effects on lowering cholesterol levels has led to the increased awareness of the health
benefits of soy protein. However, the presence of high levels of phytoestrogens in
soybeans has also led to concerns over the potential safety of soy foods. This review will
focus on the cardioprotective benefits of legumes and discuss the hypothetical concerns
regarding the constituent phytoestrogens.
S23
Whole grains, refined grains and fortified refined grains: What's the
difference?
JOANNE L SLAVIN
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S23 - October 2000
Whole grains, refined grains and fortified refined grains: What's the difference?
Joanne L Slavin, PhD, RD
Dietary guidance universally supports the importance of grains in the diet. The United
States Department of Agriculture pyramid suggests that Americans consume from six to
11 servings of grains per day, with three of these servings being whole grain products.
Whole grain contains the bran, germ and endosperm, while refined grain includes only
endosperm. Both refined and whole grains can be fortified with nutrients to improve the
nutrient profile of the product. Most grains consumed in developed countries are
subjected to some type of processing to optimize flavor and provide shelf-stable products.
Grains provide important sources of dietary fibre, plant protein, phytochemicals and
needed vitamins and minerals. Additionally, in the United States grains have been chosen
as the best vehicle to fortify our diets with vitamins and minerals that are typically in
short supply. These nutrients include iron, thiamin, niacin, riboflavin and, more recently,
folic acid and calcium. Grains contain antioxidants, including vitamins, trace minerals
and non-nutrients such as phenolic acids, lignans and phytic acid, which are thought to
protect against cardiovascular disease and cancer. Additionally, grains are our most
dependable source of phytoestrogens, plant compounds known to protect against cancers
such as breast and prostate. Grains are rich sources of oligosaccharides and resistant
starch, carbohydrates that function like dietary fibre and enhance the intestinal
environment and help improve immune function. Epidemiological studies find that whole
grains are more protective than refined grains in the prevention of chronic disease,
although instruments to define intake of refined, whole and fortified grains are limited.
Nutritional guidance should support whole grain products over refined, with fortification
of nutrients improving the nutrient profile of both refined and whole grain products.
S28
Nut consumption, lipids, and risk of a coronary event
GARY E FRASER
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S28 - October 2000
Nut consumption, lipids, and risk of a coronary event
Gary E FraserMBChB, PhD, FRACP
In the past many have avoided nuts because of their high fat content. The Dietary
Approaches to Stop Hypertension diet, however, recommends regular consumption of
this food along with seeds and dried beans (4-5 servings per week) as part of a diet to
control hypertension. Nuts are nutrient-dense and most of their fat is unsaturated. They
are also perhaps the best natural source of vitamin E and are relatively concentrated
repositories of dietary fibre, magnesium, potassium and arginine, which is the dietary
precursor of nitric oxide. Human feeding studies have demonstrated reductions of 8-12%
in low-density lipoprotein (LDL) cholesterol when almonds and walnuts are substituted
for more traditional fats. Other studies show that macadamias and hazelnuts appear at
least as beneficial as fats in commonly recommended diets. Whether the daily
consumption of modest quantities of nuts may promote obesity is not known with
certainty, but preliminary data suggest that this is unlikely. Four of the best and largest
cohort studies in nutritional epidemiology have now reported that eating nuts frequently
is associated with a decreased risk of coronary heart disease in the order of 30-50%. The
findings are very consistent in subgroup analyses and unlikely to be due to confounding.
Possible mechanisms include reduction in LDL cholesterol, the antioxidant actions of
vitamin E, and the effects on the endothelium and platelet function of higher levels of
nitric oxide. Although nuts may account for a relatively small percentage of dietary
kilojules, the potential interacting effects of these factors on disease risk may be
considerable.
S33
Changing the diet of a nation: Population/regulatory strategies for a
developed economy
MARION NESTLE
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S33 - October 2000
Changing the diet of a nation: Population/regulatory strategies for a developed economy
Marion NestlePhD, MPH
The principal nutritional problems of developed economies are related to the excessive
and unbalanced intake of energy and nutrients. During the 20th century, as economies
improved and food production became more efficient, conditions related to
undernutrition were replaced by epidemics of coronary heart disease, certain cancers and
other chronic conditions related to food overconsumption. In developed countries such as
the United States, obesity became the predominant public health nutrition problem. To
prevent obesity, people must consume less energy and be more active, but the food
supplies of developed economies offer their populations amounts of energy that greatly
exceed physiological need. Food overproduction causes competition in the food industry,
limits its expansion, and leads food producers to invest heavily in marketing. To increase
sales, food companies must encourage people to consume more of their products,
substitute their products for others or develop new markets. Such efforts create an
environment in which food is readily available at all times and readily overconsumed.
Marketing expenditures for any single food product greatly exceed the total amounts
available to governments for national campaigns to prevent chronic diseases. Existing
government policies often support this environment through price supports and other
means. To reverse obesity and its health consequences, governments need to consider
ways to address the food environment through policies in education, agriculture, school
meals, pricing, taxation and other means, as well as to develop mechanisms to fund new
programme initiatives.
S41
Plant-based diets are traditional in developing countries: 21st century
challenges for better nutrition and health
NOEL W SOLOMONS
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S41 - October 2000
Plant-based diets are traditional in developing countries: 21st century challenges for better nutrition and
health
Noel W SolomonsMD
The chronic degenerative diseases were virtually unknown in original hunter-gatherer
societies. At the dawn of the 21st century, however, they represent the most important
public health challenge to populations of both the industrialized, affluent nations of the
temperate zones and the low-income developing countries of the tropics. The developing
countries most closely reflect the legacy of our traditional foreparents while constituting
three-quarters of the world's populace and public health interest. For economic,
traditional, religious and cultural reasons, the majority of the dietary fares in the
developing world are largely plant based. This is associated with high prevalences of
deficiency states in vitamin A, iron, zinc, riboflavin and vitamin B12. Poor linear growth
and chronic energy deficiency are concomitant conditions. Conversely, the major chronic
diseases have low prevalences among the rural peasantry and tribal groups, with the
exception of gastro-esophageal cancer, osteoarthritis and cataract. As a site for intensive
research in food and nutritional sciences, Guatemala provides important lessons about the
origin and evolvement of a congruent plant-based diet within a food system and which
factors of demographic expansion, urbanization, environmental stress and food
technology will carry it through the 21st century. We can conclude that, whatever was the
'original' dietary pattern of pre-agricultural humankind, a plant-based diet regimen
provides the lowest content of promoters and the highest content of inhibitors of
metabolic dysregulation that lead to the major causes of disease and debility in adults
over 40 years of age. For developing countries, the challenge is to maintain and reinforce
the traditional eating patterns while improving their delivery of micronutrients and
obviating any adverse environmental consequences in their traditional preparation
patterns. For developed countries, there is an opportunity to find a 'road map' of
guidelines to allow correction of current, pathogenic dietary and lifestyle patterns by
examining the food-ways of traditional developing societies' cuisines.
S55
Clinicians changing individual food habits
MARK L WAHLQVIST
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S55 - October 2000
Clinicians changing individual food habits
Mark L Wahlqvist AO, BMedSc, MDBS (Adelaide), MD (Uppsala), FRACP, FAIFST, FACN, FAFPHM
There is ample evidence from repeat food surveys that people are actually and passively
changing their food habits. Understanding the reasons for this are vital to any efforts by
clinicians to enable individuals to move in an increasing healthful direction with their
food intake, and to dispel the pessimism that often prevails about the ability to make a
useful contribution to nutritional status by changing food intake. Current success and
failure rates are predicated on inadequate methods and inappropriate outcome measures,
rather than an inability to achieve outcomes. Factors that allow for or encourage change
are food availability, exposure to new food experiences, food memory, pleasure, eating
with peers or companions, health interest and changing constructs and beliefs about food.
It is possible to change the health impact of food by non-food means like physical
activity, stress management, recreational activities, improved relationships, changing the
work environment and through adequate sleep (including siesta). Yet another
consideration is that the full consequences of food choice are not appreciated with more
and more food-health relationships being defined (e.g. with cataract, macular
degeneration, in depression and cognitive function). These various approaches require a
management strategy that underpins the field of behavioural therapy. In this approach it is
possible to make progress through small but consequential changes, like climbing the
stairs, or increasing intake of particular foods like fish or drinking more water; and
exploring and contracting ways to do these things.
S60
Optimizing the plant-based diet
JIM I MANN
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S60 - October 2000
Optimizing the plant-based diet
Jim I MannDM, PhD, FRACP, FFPHM
Any attempt to optimize a plant-based diet necessitates an identification of the features of
the diet which confer benefit as well as any which may be associated with detrimental
effects. The former task is more difficult than might be assumed as there is no doubt that
some of the apparent health benefits observed amongst vegetarians are a consequence of
environmental determinants of health which characterize groups of people who choose
vegetarian diets, rather than dietary practices. This review will consider the major health
benefits of plant-based diets, the specific foods or nutrients which confer the benefits as
far as can be ascertained from present knowledge, potential nutrient deficiencies
associated with a plant-based diet and nutritional strategies that can be employed to
prevent any such deficiencies.
S65
Eat Well Australia: Developing a national strategic framework for public
health nutrition
JOHN CATFORD
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S65 - October 2000
Eat Well Australia: Developing a national strategic framework for public health nutrition
John CatfordDM, FRCP, FAFPHM
In Australia, diet-related disease ranks alongside tobacco-related disease as the most
important preventable health area, accounting for at least 10% of the total burden of
disease. A population approach to improve the nutrition of all Australians is a vital
contribution to the nation's overall health and well-being, yet action has often been
ineffective, uncoordinated and poorly resourced. Through the National Public Health
Partnership's nutrition group, SIGNAL, an ambitious work program has been commenced
to address this situation. This includes the development of a national framework for
action in public health nutrition 2000-2010. Following extensive consultation with health
groups and the food industry, the strategy, Eat Well Australia, is now in a late stage of
development. Key priorities have been agreed and focus on: (i) Aboriginal and Torres
Strait Islander people; (ii) vulnerable groups; (iii) maternal and child health; (iv)
overweight and obesity; and (v) fruit, vegetables and legumes. Eat Well Australia should
provide a new pathway for more concerted and integrated action from a wide range of
organizations and interest groups. As a core component, SIGNAL has also developed an
action plan to promote comsumption of fruits, vegetables and legumes, which should
mobilize responses at local, regional and national levels. Close cooperation between the
food industry and the governmental and non-governmental sectors will be vital for
success. A partnership platform is needed with clearly defined directions, operating
principles and roles and responsibilities. Encouragingly, new and energetic alliances are
now developing, which will be supported by Eat Well Australia.
S72
Changing what we eat: Can a professional association play a role?
SANDRA CAPRA
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S72 - October 2000
Changing what we eat: Can a professional association play a role?
Sandra CapraBSc(Hons), MSocSC, Dip Nutr&Diet, PhD
Professional associations have traditionally focused their activities in the provision of
services to members. However, this need not be their only role. The Dietitians
Association of Australia has chosen to take a proactive approach to changing the way that
the Australian people eat. Through a variety of strategies assisted by partnerships with
industry, the Association has been able to increase skills of individual members, provide
skills to other health providers, increase advocacy, implement health promotion programs
and use the media to provide nutrition messages. Encouraging results have been achieved
to date that support such a role for professional associations.
S76
Colorectal disorders: A dietary management perspective
GRAEME P YOUNG
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S76 - October 2000
Colorectal disorders: A dietary management perspective
Graeme P YoungMB, BS, MD, FRACP
Dietary lifestyle is relevant for prevention and treatment of various colorectal conditions.
Colorectal disorders have significant morbidity and mortality in a western-style
community, particularly irritable bowel syndrome (IBS), colorectal cancer, haemorrhoids,
constipation and diverticular disease. This review addresses how bowel health can be
maintained, what foods and dietary lifestyles are associated with risk for disease and what
foods are of real value in management. Bowel health is that state where the individual is
satisfied with defaecation, the diet does not create undue risk for disease and lumenal
contents maintain an intact and functional mucosa. Bowel health depends on a healthy
dietary lifestyle, but in particular on an adequate intake of non-digestable dietary
polysaccharide. Diet influences biology in part by altering the lumenal environment.
Effects such as high butyrate levels, lowered pH, a predominance of 'healthy'over
'unhealthy' bacteria, rapid intestinal transit, high faecal bulk, a non-leaky epithelial
barrier, adsorption of dietary carcinogens by fibre, low bile salt concentrations, reduced
generation of toxic bile salts or protein derivatives and provision of certain bioactive
substances are seen as beneficial. Diet influences future risk for colorectal cancer
(vegetables, animal fats, polysaccharides amongst others) and for diverticular disease
(fibre). Adequate fibre and resistant starch can improve constipation and anorectal
conditions such as fissure and haemorrhoids. The role of diet in managing patients with
IBS is complex. Fibre may worsen symptoms in severe cases of IBS, diverticular disease
and inflammatory bowel disease. Certain carbohydrates of limited
digestibility/absorbability, such as lactose, fructose and sorbitol, can precipitate IBS
symptoms. Low fat, high fibre diets may reduce recurrence of colorectal adenomas. Diet
has a significant role to play in colorectal disorders.
S83
Evolution of the diabetic diet: Fats and fallacies
LESLEY V CAMPBELL
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S83 - October 2000
Evolution of the diabetic diet: Fats and fallacies
Lesley V CampbellMB, BS, FRACP, FRCP (UK)
The Diabetes Control and Complications Trial and United Kingdom Prospective Diabetes
Study (UKPDS) trials have provided evidence for the pivotal importance of optimizing
glycaemic control to prevent complications in type 1 and 2 diabetes mellitus. Both
patients and diabetes professionals consider lifestyle change and appropriate medication
as cornerstones for achieving good glycaemic control. The frequent reversals in the
recommended diabetic diet in the past century warn that in the nutritional area the
hypotheses are many, but the proofs are few. In type 1 diabetes, the patient is still advised
to spread out carbohyrate foods during the day with three short-acting insulin injections
at meal times to minimize postprandial hyperglycaemia. In type 2 diabetes, weight loss is
the major target, because 80% of patients are overweight or obese. However, it is salutory
to note that in the UKPDS trial, no modality of treatment delayed the relentless
deterioration of glycaemic control in type 2 diabetes, the extent of which was predicted
by the insulin secretion. Controversy still exists regarding whether lowering the dietary
fat enhances weight loss of itself and whether dietary carbohydrate, fat and fibre
influence insulin sensitivity and glycaemia. The American Diabetes Association's
evidence-based recommendations currently offer a choice between a high carbohyrate
and modified fat diet, with monounsaturated fat replacing the saturated fat instead of
carbohydrate. The role of omega-3 fatty acids in man is not resolved. The reason for the
surprising lack of definitive evidence lies in the limitations of nutritional research. Under-
reporting of diet is common and dietary assessment tools are often inaccurate. Sustained
weight loss is unattainable by the majority of patients, perhaps because of the strongly
genetic nature of obesity and the sedentary lifestyle. Compliance may be improved by
suggesting small, sustained dietary changes, setting small weight loss targets and
encouraging a permanent increase in total activity.
S86
Food for prevention of coronary heart disease: Beyond the low fat, low
cholesterol diet
DAVID M COLQUHOUN
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S86 - October 2000
Food for prevention of coronary heart disease: Beyond the low fat, low cholesterol diet
David M ColquhounMB, BS, FRACP
The single major cause of death throughout the world is coronary heart disease.
Prevalence is stable or decreasing in North America, Australasia and most of Europe,
while rapidly increasing in eastern Europe, Asia and Africa. Atherosclerosis is the
underlying pathology. This is one of the classic lifestyle diseases on the background of
genetic susceptibility. Diet plays a key role in the initiation and progression of coronary
heart disease. A low total fat diet is almost universally recommended throughout the
world. However, the most successful secondary prevention diet trials have used
modification of fat, rather than decrease in total fat per se. Successful diet trials suggest
that diet modification is as effective as accepted drug therapy to prevent recurrent
coronary events, and importantly is very cost effective. Marine lipid supplementation has
been demonstrated beyond reasonable doubt to decrease total mortality and in particular
sudden death in patients who have survived their first myocardial infarction. Large-scale
diet intervention trials are indicated to improve the scientific basis for dietary
recommendations to prevent initial and recurrrent coronary heart disease.
S91
Nutritionally enhanced cereals: A sustainable foundation for a balanced diet
ROBIN D GRAHAM, JULIA M HUMPHRIES, JULIE
L KITCHEN
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S91 - October 2000
Nutritionally enhanced cereals: A sustainable foundation for a balanced diet
Robin D GrahamDAgrSc Julia M HumphriesBAgSc(Hons) and Julie L KitchenBAgSc(Hons)
Three nutrients, iron, zinc and pro-vitamin A, are widely deficient in humans, especially
among low socio-economic groups in developing countries, but they remain significant
concerns in industrialized countries as well. Cereals provide the majority of the intake of
these nutrients in low-income families. Moreover, these three nutrients may interact
synergistically in absorption and function to such an extent that there are potentially huge
advantages in providing all three together in the one staple food. Because of this, they
may be more bioavailable to deficient individuals than current thinking allows. To do so
would provide a sound basis on which to build a better balanced diet for nutritionally
compromised individuals. Genetic variation in nutrient composition exists in cereals and
can be exploited in conventional breeding programmes and through gene technology.
Cultural techniques, including fertiliser technology and organic farming, have also
impacted upon the nutrient composition of cereals. Human iron and zinc intake can be
doubled at least, and essential carotenoid intakes can be increased dramatically.
Preliminary feeding trials with nutrient-dense grains have been encouraging. Moreover,
nutrient-dense seeds also produce more vigorous seedlings and higher grain yield in soils
where these nutrients are poorly available, so that to a significant extent agronomic and
health objectives coincide. New varieties are rapidly adopted, especially where there are
yield advantages, ensuring maximum impact without new inputs. This approach is
potentially more sustainable than fortification and supplementation programmes because
intake is continuous, which is especially important for zinc because it is needed almost
daily.
S97
Food security and sustainability: Are we selling ourselves short?
JOHN COVENEY
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S97 - October 2000
Food security and sustainability: Are we selling ourselves short?
JOHN COVENEY
This paper deals with the question: do some food systems engender a more positive social
environment than others, and does this matter? The pressure to generate financial capital
from food production is enormous, especially for a country like Australia, and financial
imperatives clearly drive choice of food production methods. Many have argued that
environmental costs of food production are hardly ever factored into the profitability
equation and the notion of sustainable development represents a position where
consideration is given to environmental concerns while at the same time maximizing
economic returns. While the importance of choice of food system in order to benefit the
natural environment has been argued for, another environment
environment
S101
remains relatively underexplored.
Food and health economics in the 21st century
that of the social
PHILLIP K RUTHVEN
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S101 - October 2000
Food and health economics in the 21st century
Phillip K Ruthven
People are living longer and with more pain-free and comfortable lives as we begin the
21st century in 2001. Life expectancy was just 53 years (for males) in the beginning of
the 20th century and is now 78 years. One in four children born in 2000 are expected to
live beyond 100 years. There are many reasons for such advancement: fewer accidents,
particularly work and travel related; better diets; and more and better health care.
Australia's health spending is around 8.4% of gross domestic product, ranking eighth in
the Organization for Economic Cooperation and Development, and has arguably one of
the best value-for-money programs in the world. However, the make-up of the $50 billion
expenditure in 2000 is reflecting changes from the past. We are moving away from
institutional health care, embracing preventative care and 'alternative' approaches via
fitness, diets, well-being programs and more natural remedies. Few, however, would
suggest that pharmacology and surgery (including less invasive) are not important; they
are. Food continues to play a vital role in our healthy lives. In 2000 we will expend
approximately $90 billion on food and liquor prepared and consumed at home, or
prepared and/or eaten out of the home. The latter is increasing as we outsource more and
more of our meals (currently one in five). Our diet is changing. We are consuming more
poultry, seafood, fruit and fruit products (including juices), vegetables, grain products
and wine. We are consuming less red meat and meat products, eggs, oils and fats, sugars
and beer. Our lifestyles are changing dramatically as we leave the Industrial Age further
and further behind. The New Age began around 1965 (and should itself be displaced
around 2040). Included in these changes are working wives, outsourcing of more and
more household chores, embracing the Internet and electronic 'guardian angels' and much
more. It promises to be an exciting, healthier and longer living new century.
S103
Food and consumers: Where are we heading?
ANTHONY WORSLEY
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S103 - October 2000
Food and consumers: Where are we heading?
Anthony WorsleyBSc(Hons), PhD
The translation of recent advances in nutrition sciences into enhanced population health
and well-being depends on the development of a deeper understanding of human food
consumption patterns and the factors which influence them. Food consumption patterns
are dynamic and are influenced by complex, interrelated biological, social, cultural and
psychological processes. These are evident in recent attempts to discriminate nutrition
and health-related dietary patterns in terms of consumer lifestyles and belief systems.
Consumers' pursuit of health and well-being through food consumption will be illustrated
through reference to recent Australian studies. Some of the effects of societal changes
associated with globalization: gender, work and family roles; materialism; information
technology; and increasing longevity, on food consumption trends will be explored.
Finally, the implications of these developments for the activities of health professionals,
food companies and other agencies will be raised.
S108
What makes a functional food functional?
PETER RC HOWE
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S108 - October 2000
What makes a functional food functional?
Peter Rc Howe MSc, PhD
Functional foods are foods that, by nature or design, can deliver benefits beyond that of
sustenance. They bridge the traditional gap between food and drugs, offering consumers
greater opportunity to take their health care into their own hands. Rapidly increasing
knowledge of the physiological effects of nutrients and their potential health benefits
offers exciting prospects for the food industry and consumers alike. However, we must
ensure that newly developed functional foods are indeed functional. The mere presence in
a food of nutrients with well-publicised health attributes can infer that the food will
deliver health benefits. We need to be certain that it will be efficacious for the indication
specified and the nature and extent of benefit will be clearly understood by consumers.
With the introduction of health claims, the onus will be on food manufacturers to provide
scientific substantiation based not only on the literature related to an active nutrient, but
also on intervention trials that demonstrate bioavailability and efficacy of the nutrient
when delivered in a specific type of food. Such an approach, while demanding in terms of
research and development investment, offers significant opportunities for product
innovation. We can extend the variety of foods through which consumers may source a
particular health-giving nutrient. Moreover, recognizing that a particular condition such
as heart or bowel health may be influenced by more than one type of nutrient,
manufacturers can design and evaluate unique foods with appropriate combinations of
nutrients to optimise health status. Even though a new type of food may be shown to be
efficacious in short-term, controlled clinical trials, can we be certain that consumers will
derive long-term benefits free from adverse affects? Will food manufacturers undertake
postmarketing surveillance or will this task be left to consumer watchdogs? The transition
from traditional foods and herbal remedies of uncertain value to designer foods with
guaranteed health benefits could be facilitated by adopting aspects of the pharmaceutical
approach to substantiation and regulation.
S113
Gene technology and future foods
SIMON ROBINSON, NIGEL SCOTT, ANGELA GACKLE
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S113 - October 2000
Gene technology and future foods
Simon RobinsonPhD Nigel ScottPhD and Angela GackleBSc
Molecular biology is revolutionizing biology, agriculture and medicine. It is now possible
to isolate and sequence the basic genetic material (DNA) from any organism and
techniques have been developed to copy and 'cut and paste' DNA molecules to produce
new combinations. This has led to the development of genetically modified (GM) plants
by the targeted introduction of a small number of well-defined genes directly into the
cells of an existing plant variety to improve its quality or performance. Early efforts
concentrated on major field crops, such as corn, soybeans and canola. Products from
these plants, such as oil and flour, are components of many processed foods, so the rapid
adoption of GM commodity crops in the United States has led to widespread appearance
of GM plant material in foods. The initial traits targeted, such as herbicide tolerance and
pest resistance, provide improved production efficiency with benefits for agrochemical
and seed producers, farmers and the environment, but little obvious benefit to consumers.
The second generation of GM plants will provide consumer benefits and will extend
beyond bulk commodity crops. Genetically modified plants with improved flavour,
nutritional composition and shelf life are currently being developed in a range of grains,
fruits and vegetables. Genetically modified plants pose no risks for human health beyond
those that we readily accept in other foods. In most developed countries, GM plants
undergo thorough testing and evaluation, well beyond that required for a conventionally
bred new variety, and this should ensure that the current high safety and quality of foods
is maintained.
S119
Recommended dietary intake levels for phytochemicals: Feasible or
fanciful?
IVOR E DREOSTI
Asia Pacific Journal of Clinical Nutrition
Volume 9 Issue Suppl. Page S119 - October 2000
Recommended dietary intake levels for phytochemicals: Feasible or fanciful?
Ivor E DreostiPhD, DSc
Phytochemicals are biologically active compounds, found in plants in small amounts,
which are not established nutrients but which nevertheless seem to contribute
significantly to protection against degenerative disease. At present, most interest in
phytochemicals is focused on the polyphenolic flavonoids and on the carotenoids,
although allium compounds, glucosinolates, indoles and coumarins have also received
attention, especially with respect to cancer. Mechanistically, phytochemicals are thought
to act in many ways, which include their activity as anti-oxidants, antibacterial/viral
agents, phytoestrogens and as inducers or inhibitors of a variety of key enzymes.
Recommended dietary intakes (RDI) are the levels of intakes of essential nutrients
considered adequate to meet the known nutritional needs of practically all healthy
persons. To be regarded as an essential nutrient, a dietary component must be a single
identified compound or a close derivative. It should have a demonstrated key biological
role and characteristic deficiency syndrome, both of which should respond to nutritional
manipulation and are used as a basis for setting an RDI. In these terms, allocating RDI to
phytochemicals is problematic, due in part to the large number of chemically different
phytochemicals and the lack of a distinctive deficiency syndrome or inherent
physiological role in almost all cases. Accordingly, allocation of a single RDI to a general
class of phytochemicals would be impracticable, although for an individual
phytochemical it may be feasible if acceptable justification for an RDI is extended to
include optimum health and evidence is forthcoming of a key inherent role for that
compound in maintaining optimum physiological function. However, a distinction will
need to be drawn between phytochemicals that participate as integral components of an
essential biological system and become recognized as nutrients and those that act as
valuable non-nutrient health-promoting agents. Both classes of phytochemicals occur in
foods and both could be incorporated into functional foods. Both could be addressed in
recommendations such as dietary guidelines, but at present only established nutrient
phytochemicals would be eligible for an RDI.