Globalisation, Coca-colonisation and the 'diabesity' epidemic - ATSE: Australian Academy of Technology and ...
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Number 143 Australian academy of Technological sciences and engineering (ATSE)
december 2006
In This issue:
Contributors discuss health, diet, food and food safety; our President says farewell
and participants report the findings of the Scanlon Project
Globalisation, Coca-colonisation
and the ‘diabesity’ epidemic
between obesity and type 2 diabetes is very strong, in fact
so strong that the term ‘diabesity’ is being frequently used
By Paul Zimmet to better describe the current twin epidemic.
A
pzimmet@idi.org.au Unfortunately, most nations are poorly prepared
2005 World Health Organization (WHO) to tackle this twin epidemic effectively. Governments
report, Preventing Chronic Diseases: A Vital remain largely unaware of, or are complacent about, the
Investment, shows that non-communicable existing magnitude of the NCD challenge. More im-
diseases (NCDs) dominated by diabetes and portant is the fact that they ignore the future increases
obesity are causing twice as many deaths as caused by in obesity and diabetes and their serious complications
infectious diseases, maternal/perinatal conditions and such as cardiovascular disease (CVD). Failure to act now
malnutrition combined. The report states that with- on the direct costs of healthcare and the indirect costs
out action, 388 million people globally will die from from loss of productivity and premature morbidity and
chronic diseases such as diabetes and heart disease in mortality is very likely to cripple the health budgets of
the next decade. It is against this background that we many nations, both developing and developed.
are facing a global threat from the spectacular rise in With this major international challenge in mind, in
the prevalence of type 2 diabetes and obesity and their May 2005 the International Diabetes Institute, in con-
consequences. junction with the Monash University Institute of Glo-
In terms of diabetes, the number of cases has reached bal Movements and the UK-based Nuffield Trust, held
pandemic proportions and will continue to increase sharp- a meeting of 25 leading world experts from a number
ly. The Melbourne-based International Diabetes Institute of disciplines in London. The objective of the meeting
has predicted that the number of people with diabetes was to assess the impact of globalisation on health in
will almost double within just one generation, from the both developed and developing countries with respect
present 250 million to 380 million in 2025. The linkage to NCDs such as CVD, diabetes and obesity.
u page 2
ATSE is an independent body of eminent Australian engineers and Honorary Editor: Dr D C Gibson FTSE Technical Consultant: Dr Vaughan Beck FTSE
www.atse.org.au
scientists established to promote the application of scientific and Australian Academy of Technological Sciences and Engineering (ATSE)
engineering knowledge to practical purposes. Focus is produced to serve Address: Ian McLennan House, 197 Royal Parade, Parkville Vic 3052
this goal. Postal Address: PO Box 355, Parkville Vic 3052
Opinions expressed in this publication are those of the authors, and do Telephone: 03 9340 1200 Facsimile: 03 9347 8237 Email: editor@atse.org.au
not necessarily reflect the views of ATSE. Material published in Focus may ACN 008 520 394 ABN 58 008 520 394
be reproduced provided appropriate acknowledgement is given to the Print Post Publication No 341403/0025 ISSN 1326-8708
author and the Academy. Focus design and production: www.coretext.com.au
cover story: nutrition and health
u From page 1
from the editor
The conference focused on how the world has come
by a chronic disease health calamity that rivals or even
exceeds the emergence or re-emergence of devastating
This is the sixth edition of Focus in its new format. In the past five issues communicable diseases, including severe acute respira-
contributors have discussed and debated great teaching, nuclear energy,
tory syndrome (SARS), HIV/AIDS, the Ebola virus
genetically modified crops and foods, climate change, entrepreneurship,
educating engineers and technology exploitation. In this issue they examine
and our old enemy, tuberculosis. While governments
diet and healthy foods, a hot topic for the nation right now, and participants around the world are busy preparing for an avian influ-
report the findings of the Scanlon Project, a major undertaking for the enza pandemic, they ignore the equally insidious threat
Academy. of diabetes and other NCDs! In the brief period of sev-
Also in this issue our President says farewell. We acknowledge his
eral decades, many developing nations are faced with a
stewardship of the Academy, his defence and advocacy of good science and
his plea for the scientific debate to be separate from and complementary double burden of communicable diseases and NCDs,
to the social and political debates of our time. He is not impressed by five- placing enormous pressure for solutions on WHO and
minute, doorstop explanations of climate change. He, better than most, other international and regional nongovernmental
understands the difficulty in distinguishing trends in the midst of large- agencies. The NCD burden has now become one of the
amplitude, low-frequency and broad-bandwidth random noise. His appeal
major threats to human health in the 21st century
for calm, deliberate debate in the face of mounting public and political
hysteria is what the Academy is about.
In its current format Focus is a platform for deliberate debate. It Globalisation and world health
is a vehicle for Fellows and other contributors to express views about Globalisation of the world economy has become a
important national issues, to show that there are shades of grey that must fashionable subject for the international economic
be considered, and not just the blacks and whites of popular journalism. Is it
community. We are constantly reminded that we are all
doing its job? Should it do more? These questions do not keep an honorary
editor awake at nights. Perhaps they should. If you have a special interest members of the global village, but this means very lit-
topic you would like examined, please do not hesitate to raise it via a request tle to people in areas subject to natural disasters and in
to editor@atse.org.au. The Academy has an extraordinary breadth and depth sites of major political tension and poverty. In fact, glo-
of knowledge and experience available from within its Fellowship. balisation may afford a weak disguise for a misguided
‘If it ain’t broke don’t fix it’ – the first law of Australian farming; perhaps
movement that attempts to integrate developing na-
the first law of Australian life. ‘She’ll be right’ – the second law. In the seventh
year of the worst drought in the nation’s recorded history, and facing tions into the paradigm of western socioeconomic and
the prospect of a hot, tinder-dry summer, it is easy to see why country healthcare models.
Australians have such a dry, laconic, laidback sense of humour. They know We could have hoped for improved health out-
the bad times will pass and the good times will come again, but when?
comes in many developing nations after so many years
Our nation’s two-speed economy has the mineral-rich states of
Queensland and Western Australia enjoying boom conditions while the
of public health research. Unfortunately, in most in-
rest of the country ponders an approaching dip in the property cycle, and stances the research findings have not been translated
an unhealthy level of mortgage debt. One thing we share is the terrible into improved health outcomes. There are no better ex-
drought, and our primary producers carry the greatest burden. amples than those of obesity and type 2 diabetes. They
Spare a thought for our country cousins this Festive Season.
are epidemic in the peoples of many developing nations
A Message from the Vineyard
If all be true that I do think,
and in the economically disenfranchised minorities of
There are five reasons we should drink; many developed countries, including the US and Cana-
Good wine – a friend – or being dry – da, and indeed in our own Indigenous community.
Or lest we should be by and by – Globalisation does not apply just to economic
Or any other reasons why
change but also to the human diet and lifestyle. So,
– Reasons for Drinking, Henry Aldrich 1648-1710
tragically, the diabesity epidemic is linked to the socio-
ATSE Office Bearers economic revolution and its impact on the traditional
and executive way of life, including nutritional and physical activity
Deadlines 2007 President patterns. This means that the solution, that is the pre-
Deadlines for the receipt of copy for Dr J W Zillman AO president@atse.org.au
forthcoming issues of FOCUS are: vention and control of these NCDs, is not entirely in
9 February 2007 Vice Presidents
11 May 2007 Dr D V Clark AM vicepresdvc@atse.org.au the hands of individuals and the medical community. It
10 August 2007 Mr P J Laver AM viceprespjl@atse.org.au is, as stated in the 1999 WHO report, a major respon-
9 November 2007
Articles and opinion pieces of 800 Honorary Treasurer sibility of public and social planners, private enterprise,
Dr J A Eady hontres@atse.org.au
www.atse.org.au
to 1200 words in length on issues of
national importance will be welcomed.
economists and politicians. We might ask, given the
Honorary Secretary
Contributions should be addressed to Professor T F Smith AM honsec@atse.org.au rather poor record of implementation of a whole chain
The Editor at Academy Headquarters,
or by email to editor@atse.org.au. Ceo of international agreements and declarations, can we
Electronic communication is preferred. Dr J Dodgson johnfd@atse.org.au trust them to meet the NCD challenge?
nutrition and health
The epidemiological perspective control of type 2 diabetes and the other major NCDs
From a historical perspective, until the latter part of the can be cost- and health-effective through an integrated
19th century the main causes of morbidity and mortal- lifestyle and behavioural approach to NCD disease
ity in all nations were epidemics of communicable dis- prevention and control.
eases, including typhoid, cholera, smallpox, diphtheria
and influenza. Although some of these diseases remain The view from London
epidemic in Third World countries, industrialisation A wide range of issues were covered at the London
and progressive modernisation of many communities globalisation and health meeting at the Nuffield Trust.
have resulted in major improvements in housing, sani- More active intervention at government levels is essen-
tation, water supply and nutrition. The discovery and tial, which means governments ceasing to take their tra-
availability of antibiotics and vaccines have radically ditional stance: that these matters must be left to individ-
changed the profile of diseases, initially in developed ual choice. There is an urgent need for economic analysis
countries and later in many developing countries. Con- of the full health consequences, including workforce is-
sequently, these improvements in public health have sues, of overweight and obesity and their cardiovascular
led to dramatic reductions in mortality from infectious consequences, to see whether increased investment in
diseases. Paradoxically, there has been a remarkable in- prevention now would lead to long-term savings.
crease in the prevalence of risk factors for NCDs such There is an immediate need for the diabetes, obes-
as type 2 diabetes, CVD, hypertension and strokes. ity, cardiovascular and public health communities to
In his book The Call Girls, the late Arthur Koestler lobby and mobilise politicians, other international and
coined the term ‘Coca-colonisation’ to describe the im- regional agencies – such as the United Nations De-
pact of the Western way of life on developing countries. velopment Programme (UNDP), the United Nations
The devastating results of Western intrusion into the Children’s Fund (UNICEF), WHO and the World
lives of traditional-living indigenous communities can Bank – to address the socioeconomic, behavioural,
now be seen from the jungles of Brazil to the remote and nutritional and public health issues that have led to
idyllic atolls of the Pacific. Quite apart from the socio- the NCD epidemic. A multidisciplinary approach by
economic aspect, the health impact is disastrous. There governments that involves multiple ministries such as
are epidemic diabetes rates in most Pacific island popula- health, finance, education, sports and agriculture can
tions and type 2 diabetes now affects up to 30 per cent all contribute to a reversal of the underlying socioeco-
of adults; before World War II it was virtually unknown. nomic causes of the problem. These diseases will cause
This picture is mirrored in disadvantaged communities havoc, and the socioeconomic cost through family dis-
in developed nations, for example Native Americans, Af- ruption, loss to the workforce and premature mortality,
rican Americans and Mexican Americans in the US, Na- coupled with the public health burden on primary, sec-
tive Canadians, Indigenous Australians and Torres Strait ondary and tertiary healthcare services in poor nations,
Islanders and New Zealand’s Maori community. is already exacting a high economic toll.
Although the global NCD epidemic has become
a matter of enormous concern to WHO and public Conclusions
health authorities in both developed and developing The world community has been very slow to react to
nations, the resources applied to meet this challenge are the problem of the NCD epidemic and the urgent need
minuscule. For example, the WHO budget for NCDs to address the prevention issues. This has been further
is less than five per cent of its total. Globally, type 2 dia- complicated by the recent re-emergence of devastating
betes accounts for more than 90 per cent of all cases of communicable diseases mentioned earlier. The NCD
diabetes. Not only is the prevalence of type 2 diabetes explosion will not be prevented by diet and exercise
increasing, but the age of onset is becoming younger, alone! We need to see new imaginative strategies and
with an increasing number of children and adolescents major, dramatic changes in the socioeconomic and cul-
now being diagnosed. tural status of people in developing countries and dis-
One of the factors driving the creation of the Lon- advantaged and minority groups in developed nations.
don meeting was the urgency to highlight the need Global concern about our ecosystem culminated in
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for strategies to prevent the emerging global epidemic an international talk-fest in 1992: the UN Conference
of diabesity and its cardiovascular consequences. Evi- on Environment and Development in Rio de Janeiro.
dence-based interventions include lifestyle and behav- This resulted in the Rio Declaration on Environment
ioural change and tobacco control. The prevention and and Development. The conference participants were
nutrition and health
particularly conscious of the much-feared impact of Professor Paul Zimmet AO FTSE FRACP FRCP, Foundation
Director of the International Diabetes Institute, is a Professor
global warming on the future of humanity. at Monash University and the University of Pittsburgh. His
There is now an urgent need for a similar interna- research in Pacific and Indian Ocean populations has provided
new insights into the genetic and environmental contribution
tional meeting (a ‘Kyoto health’) to consider the impact
to diabetes and obesity. He has more than 600 publications and
of globalisation on health along the lines of meetings is co-editor of the International Textbook of Diabetes Mellitus
that have looked at the impact of globalisation on the and The Epidemiology of Diabetes. In 2001, he received an AO
for services to medical research of national and international
environment. significance, particularly in the field of diabetes.
The need for a new food component density (whether achieved by local
nutrition science biodiversity or trade) and therefore dietary quality for
our mostly omnivorous species, Homo sapiens, which
needs food variety. They are also accentuated by low re-
By Mark Wahlqvist silience or hazardous ecosystems, whether on account
I
mark.wahlqvist@adm.monash.edu.au of water supply, sanitation, buffer zones for infectious
n the past, nutrition science has built an under- agents or climatic harshness.
standing of food composition and of its nutrition- What is increasingly apparent is that limited energy
al value; which is to say how it meets physiologi- expenditure, with changes in domestic, occupational,
cal needs and may reduce the burden of disease transport and recreational activities, is a major factor
through adequacy and quality. that limits, in turn, the need for energy intake and the
Increasingly, the sustainability of the food supply ability to have enough nutritious food, placing more
has come under scrutiny, not just in Malthusian terms and more emphasis on the need for food of high nutri-
of population and production, but on account of the ent density. This in turn requires a greater and greater
nature of the whole food chain with its complex and reliance on non-renewable energy and other resources.
changing environmental relationships – hence, the In addition, our work patterns are less conducive
emergence of ‘eco-nutrition’. to eating patterns with family and with societal checks
Again, the social and economic effects of the food and balances and are more directed towards style of liv-
chain, from agriculture or fishing to food choice and ing, in turn potentially adverse for nutritional wellbeing
consumption, cannot be ignored by nutrition science. and health. One of the unfortunate results of the quest
This means that a reconstruction of nutrition science is for resources without regard to personal or community
under way, with the dimensions of environmental sci- wellbeing is the risk of conflict over the ownership of
ence and socioeconomics being added to those of the these resources, which is one of the greatest causes of
food and biomedical sciences and technologies. hunger and poverty.
Resource mismatch and nutritional health The future food supply and our health
Most of the world’s nutrition problems stem from a mis- As we become more and more remote from our sources
match between resources and nutritional needs. At one of food, we have less first-hand knowledge of how to
end of the spectrum there is too little food and, at the make healthy choices and of the environmental costs of
other, more than enough to meet energy needs, with a delivery. Consequently, the social role of food, which is
spectrum of disorders of energy imbalance. These are one of the ways it delivers health, will be compromised.
compounded by insufficient nutritionally favourable The health problems that we regard as nutrition-
related today, such as protein energy under-nutrition,
Most of the world’s certain immunological deficiencies, food-borne illness,
micro-nutrient deficiencies and so-called chronic dis-
nutrition problems eases (such as obesity, diabetes, cardiovascular disease,
certain cancers, osteoporosis and fracture) will change.
stem from a mismatch This is because how we produce and obtain our food
(for example, high dependency on poultry, recognised
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between resources and need to eat more fish, fruits and vegetables) may com-
promise ecosystems and allow for new human patho-
nutritional needs gens, and because our own nutritional status will alter
our disease susceptibility.
nutrition and health
It is hard to know how this will work out and nutrition science and scientist: the importance of Africa and
over what timeframe, but it is likely to be within a its capacity. Journal of Nutrition 2006; 136:1048-1049
generation. Mark L Wahlqvist AO FTSE is an eminent nutritionist and
In the future, nutrition policy will need to be more major figure in medicine and public health. He has held chairs
in either human nutrition or internal medicine for more than
and more community-sensitive and take into account, two decades and now holds honorary/visiting professorships
in integrative fashion, biomedical, environmental and at Monash University and Zhejiang University, China. He
is immediate past-President of the International Union of
socioeconomic dimensions. Nutrition Sciences and has UN responsibilities in WHO and FAO.
Further reading He has been a board member of the Australia New Zealand
Food Authority for six years and Chair of the Food Safety
Leitzmann C, Cannon G, eds. The New Nutrition Science Council in Victoria. He was awarded Sweden’s Charlotta Medal
project. Public Health Nutrition 2005; 8(6A):667-804. for his work on migration and made an Officer of the Order of
Wahlqvist ML. Towards a new generation of international Australia (AO) on Australia Day 2000.
childhood obesity: an adult obesity increases risk of diabetes, cardiovascu-
adult problem? lar disease and a number of cancers in both men and
women, anything that increases risk of obesity is likely
to be harmful.
By Terry Dwyer In 2005, a research team at the Menzies Research
T
terry.dwyer@mcri.edu.au Institute at the University of Tasmania followed up the
he media frequently present stories about the sample of 8500 children who had been measured in the
rising tide of childhood obesity in Australia. Australian Schools Health and Fitness Survey in 1985,
How substantial is this trend and what are the repeating the measurements obtained in childhood.
implications of it for the future health of this Results of an analysis of the data from the first 1000
generation of Australians? subjects remeasured, now aged 27 to 35, were reported
There is only a limited amount of good data on at the National Heart Foundation Conference in Syd-
changes in body fatness in Australian children over ney in March this year. What the team found was that
time, but what is available is quite good and the pic- among those who were overweight as children, 88.1 per
ture it paints is clear. In 1985 a representative sample of cent were overweight as adults, while among those who
8500 schoolchildren, aged seven to 15, were involved were normal weight as children only half that propor-
in the Australian Schools Health and Fitness Survey. tion (45.5 per cent) had become overweight as adults.
Height and weight were measured carefully, and using So, in our society being overweight as a child does in-
standard international cut-off points 10 per cent were crease the risk of being fatter as an adult – in fact it is
determined to be overweight and another one to two very likely that you will be overweight later in life if you
per cent obese. In adults, these cut-off points would are overweight as a child.
equate to a body mass index of 25 and 30 respectively. The other reason that fatness in childhood is likely
(Body mass index is calculated by dividing weight in to contribute to ill health is that even in childhood,
kilograms by height in metres squared. For a 1.83 me- obesity causes an elevation of cardiovascular disease
tre (six-foot) male, a weight over 84 kilograms would risk factors, including high blood pressure, high cho-
have them classified as overweight and 100kg as obese). lesterol and insulin resistance, a forerunner of diabetes.
In 1997, the National Nutrition Survey was conducted The principal underlying disease process in cardiovas-
by the Australian Bureau of Statistics (ABS) using simi- cular disease – to which these risk factors contribute
lar measurement methodology in children of the same – is the formation of plaques that narrow the vessels
age. This survey found that the proportion of children supplying blood to the heart (the coronary arteries) and
either overweight or obese had increased to 20 per cent those leading to the brain. Two major US studies have
and five per cent respectively – a dramatic rise in such shown that such plaques develop during childhood and
a short period. adolescence and are present in the coronary arteries of
How important is the presence of obesity in child- 20 per cent of the population by age 20. Further, the
hood for the future health of the individual? There presence of the risk factors listed above associated with
www.atse.org.au
are two important, documented effects of childhood body fatness increase the risk of having these plaques at
obesity that suggest it is likely to adversely affect future an early age by as much as 10 times.
health. The first relates to the extent to which obesity So, childhood obesity does appear to confer a sig-
in childhood predicts obesity in adulthood; because nificant health risk to the child affected. What can be
nutrition and health
Children now have access to more attractive
sedentary entertainment options, including a
wider choice of television channels
done to counter the rise in obesity in Australian chil- changes in aerobic fitness over time and these suggest a
dren? Part of the answer lies in the possible explanation decline of approximately 0.5 per cent per year between
for the upturn in recent decades. A comparison of three 1995 and 2000 in both boys and girls. This data is highly
national nutrition surveys conducted between 1983 suggestive of a decline in physical activity over the same
and 1995 revealed an 11 per cent increase in mean period. Australia has been a pioneer in the development
energy intake for Australian girls and 15 per cent for of programs in this domain. In 1978, a randomised trial
boys aged 10 to 15 years. This alone could explain the in Adelaide primary schools, conducted by the South
trend. These extra calories may largely be coming from Australian Education Department in collaboration
a higher consumption of energy-dense processed food with the CSIRO Division of Human Nutrition, dem-
and drink. onstrated that just over one hour a day of physical activ-
In a recent study in the Geelong region, close to ity for a school term could reduce body fat by almost 10
40 per cent of energy consumed in school lunches was per cent for students involved, compared to an inactive
from biscuits, cereal/fruit bars, packaged snacks or soft control group. That program was voluntarily taken up
drinks, and 90 per cent of children consumed at least by 60 per cent of all South Australian primary schools
one of these items. and a good proportion of primary schools nationally by
The other potential explanation is that physical the early 1980s. For various reasons support of the pro-
activity in children has declined. Anecdotally, this is gram lapsed over the next decade. Maybe it is time for a
highly plausible. Children now have access to more revival of this successful locally based initiative.
attractive sedentary entertainment options, including
Professor Terry Dwyer AO FTSE, director of the Murdoch
a wider choice of television channels as well as com- Childrens Research Institute, has had a major involvement
puter-based activities. In addition, active transport to in SIDS research and, with his team, contributed important
evidence on the relationship of prone sleeping position to SIDS
school has declined as a greater proportion of parents risk. His current work focuses on the joint effects of genes and
drive children from door to door. However, there is no environment in diseases as diverse as cancer, cardiovascular
disease and multiple sclerosis. In 2000 he received a Global
good national data on physical activity trends in chil- Health Leadership Fellowship from the WHO and in 2003 was
dren. There is, nonetheless, some evidence concerning the Australian Society for Medical Research Medallist.
New cereals to help fight to affect the very people leading economic development
diseases of affluence in emerging nations. Obesity is attracting wide inter-
est as it is both a visible lifestyle-limiting problem and
By David Topping a risk factor for those diseases of affluence. The causes of
& Matthew Morell obesity are complex and seem to relate to the availability
I
david.topping@csiro.au of cheap, plentiful, energy-dense foods and a decline in
ndustrialisation has brought great physical activity through mechanisation and through an
benefits to advanced countries in increase in sedentary activities. The importance of diet
terms of improvements in the stan- in condition management is recognised, and while diet
dard of living and life expectancy. can assist in weight control, it is not a viable long-term
Public health has been served very well by better sanita- option at the population level. CSIRO and its scientific
tion and a more stable, plentiful and safer food supply. and industry partners have chosen to adopt a public
These benefits are also appearing in developing coun- health route to tackle the related problems of diabetes,
tries as affluence increases. However, these advances colo-rectal cancer and weight control through the gen-
www.atse.org.au
have come at a cost, with the ‘diseases of affluence’ pre- eration of a range of consumer food options with sub-
senting serious socioeconomic challenges in developed stantiated health benefits.
industrialised countries. These diseases include diabetes, Underpinning this strategic direction is an appreci-
heart disease and colo-rectal cancer and are beginning ation that the food supply has undergone changes with
nutrition and health
time, particularly through the increased availability of digestible. However, they do not eat it all immediately
shelf-stable, energy-dense, highly digestible foods. A but over a period of a few days, which leads to a process
great deal of attention has been paid to fat, with consid- called retrogradation, whereby the starch chains associ-
erable effort being expended in producing fat-modified ate into enzyme-resistant aggregates. It has been clearly
foods. However, another subtle change has occurred shown that this stale maize porridge does indeed con-
with time. The availability of improved raw materials tain physiologically resistant starch (RS).
and more intensive processing practices has led to an in- The health benefits of RS are not mediated through
crease in the digestibility of starch in foods, to an extent the carbohydrate, but arise as a consequence of its me-
where starch digestion is typically rapid and complete tabolism by large bowel microflora. The human colon
in processed foods. Starch is the only complex dietary is home to a large and diverse microbial system com-
carbohydrate digestible by human digestive enzymes. It prising many species, and with cell numbers probably
is hydrolysed in the small intestine and the absorbed 10-fold higher than the number of cells in the human
glucose enters the bloodstream, where it is transported body. These bacteria metabolise RS and (to a lesser
to the tissues for utilisation and storage. The human extent) fibre polysaccharides and use the energy re-
small intestine has the capacity to digest starch to com- leased for growth. This fermentation resembles that
pletion, and for a long time it was thought that all starch occurring in the bovine rumen and has similar end
consumed was digested entirely, as no starch appears in products: short chain fatty acids (SCFA). These SCFA
faeces from normal humans. However, it has become are absorbed and used for energy by the large bowel.
apparent that a physiologically significant fraction SCFA also have a number of specific actions that assist
of starch can (and does) enter into the large bowel of in improving blood glucose control, promoting bowel
healthy humans. This fraction is called resistant starch health, lowering the risk of serious inflammatory bowel
(RS), as it was first detected in the test tube on incuba- disease and (possibly) colo-rectal cancer risk. One
tion of starch with amylases (giving it the original name under-recognised aspect of RS is that its energy value
of enzyme-resistant starch). is less than 50 per cent of starch digested in the small
Much of the current interest in dietary carbohy- intestine. This is a relatively small difference but, given
drates and health came from studies with native popu- that the rate of increase in excess body weight is slow
lations in areas such as East Africa, where it was noted and corresponds to the energy of about half a slice of
that they ate diets high in unrefined cereals and were bread per day, it may be significant in the long term.
at much lower risk of the diseases of affluence than Eu- The use of modern analytical techniques indicates
ropeans living in the same environment. The latter ate that the RS content of modern processed foods is much
foods typical of western societies and the early experi- lower than historical levels, and this reduction in RS
mental data related the protective effects of the African content could contribute to the high levels of the dis-
diet to apparently increased fibre levels in the diet. Fibre eases of affluence in Australia and similar countries.
polysaccharides resist human small-intestinal digestion Further, the rate of digestion of starchy processed foods
completely, which explains their effectiveness in increas- is very rapid, giving rise to substantial excursions in
ing faecal bulk and promoting laxation. While dietary blood glucose – the glycaemic response (GR) – which
fibre has unquestioned health benefits in this aspect of leads to increased demand for insulin for homoeostasis.
gut health, it has been rather disappointing in some re- Clearly, these are undesirable attributes from a public
gards, for example in its relation to colo-rectal cancer health perspective but the sensory qualities of modern
risk. Clear protection by fibre against this malignancy processed foods make them attractive to consumers: it
has been harder to demonstrate than expected, and is hard to envisage many people expressing a preference
while greater fibre consumption is of benefit, other data for diets containing substantial portions of stale or un-
suggest that the emphasis may have been misplaced. cooked food. The challenge is to make foods contain-
Re-examination of the African diet using the more ing high-RS/low-GR food starches that are attractive
sophisticated analytical tools available now suggests to consumers. CSIRO and its partner organisations are
that they might actually be consuming less fibre than seeking to do just that through a comprehensive research
Europeans, as their diet consists largely of maize corn program. The amylose component of wheat, barley and
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porridge. What has emerged is a striking difference in rice is a particular focus of the research effort. Starch
cooking practice between the Africans and the Euro- consists of two polymers – amylose and amylopectin
peans. The former cook the porridge to gelatinise the – generally in the ratio of 1:3. Amylose is a relatively
starch, thereby disrupting its structure and making it compact, linear molecule while amylopectin is a much
nutrition and health
larger, highly branched structure. Starches containing of RS and GI in the substantiation process, in order to
increased amylose content show increased resistance to assist in product development.
digestion in foods as a result of the reduced swelling and The relationship between diet and health outcomes
dispersion of such starch granules during cooking, and is an area that is both of intense interest and consider-
because of the tendency of amylose molecules to form able scepticism for consumers. Contradictory results
insoluble enzyme-resistant complexes on cooling (the or counter-claims around particular relationships have
process referred to earlier as retrogradation). Collabo- created a wariness of adopting new foods that do not
ration with the University of Queensland and the Aus- deliver the promised benefits. However, in Australia
tralian Nuclear Science and Technology Organisation the record of consumers accepting changes in diet that
(ANSTO) in the application of state of the art NMR, are strongly substantiated and deliver benefits, such as
x-ray diffraction and neutron-scattering technologies sterol-enriched margarines, polyunsaturated fatty acids
to determine the structural attributes of starches that and higher levels of dietary fibre, shows that sound,
resist digestion is an essential part of the program. well-substantiated innovations are adopted. These
In order to increase the availability of food contain- considerations show that a strong demonstration of
ing increased levels of resistant starch, GM and non- benefit, published in internationally peer-reviewed
GM technologies are being employed to alter the starch journals and supported by successful communication
profile of cereal grains, and success has been achieved of consumer benefit, is critical to adoption. While the
with a new high-RS/low-GI barley (BARLEYmax™) research community can create the new opportunities,
and a high-amylose wheat. While the generation of the final member of the partnership required to capital-
new raw materials is important, it is also important to ise on the opportunity will be the food industry, which
develop the capability to process such grains and for- has the ultimate role in translating opportunity into
mulate food products that translate the potential of the products that consumers will buy for their health ben-
grain into a health benefit for the consumer. CSIRO efits and for their convenience, taste and appeal.
is actively involved in the research needed to generate
food products that capture the benefits while also deliv- Dr David Topping FTSE is developing gut-health research
projects within CSIRO. He is also contributing to the
ering consumer appeal. For example, chemical modifi- development of novel starches with low glycaemic response
cation of new cereal starches is being applied to generate and high resistant starch, especially in substantiating their
health benefits. He has more than 160 publications and nine
products with high RS (and greater capacity to deliver patent disclosures with specifications for a range of products
SCFA) and lower GI. Having generated such foods, it is designed to improve human health.
also critical that the consumer have confidence that the Dr Matthew Morell leads a CSIRO research program
focusing on understanding the relationships between grain
foods they purchase deliver benefit. CSIRO is work-
genetics, processing and health outcomes. This work explores
ing with the International Diabetes Institute and New opportunities for the food and export grains industry to deliver
Zealand Crop and Food Research Institute to develop foods to consumers that address the major lifestyle diseases
(cardiovascular disease, colorectal cancer, type 2 diabetes and
new technologies to speed up the in vitro measurement obesity) in foods with acceptable quality attributes.
The CSIRO Total costs Australians a phenomenal $21 billion a year.
Wellbeing Diet Research at CSIRO has identified dietary ap-
proaches that can assist Australians to improve their
By Manny Noakes lifestyle to achieve better health through managing
& Peter Clifton their weight. The CSIRO Total Wellbeing Diet was
T
Manny.Noakes@csiro.au Peter.Clifton@csiro.au created after accumulating evidence from several clini-
he prevalence of obesity in Aus- cal trials conducted at CSIRO Human Nutrition.
tralia has more than doubled in The more traditional low-fat, high-carbohydrate
the past 20 years. Its relationship diets for weight loss had been challenged by alterna-
to type 2 diabetes, cardiovascu- tive dietary approaches such as very low-carbohydrate
lar disease, some cancers and arthritis contributes to (Atkins), moderately high-protein (ZONE) or low
major morbidity, mortality and socioeconomic costs. glycemic index diets. However, the emerging body of
www.atse.org.au
Diet and lifestyle changes can be a very inexpensive ap- CSIRO and international research confirmed that vary-
proach to preventing some of these associated risks and ing the protein to carbohydrate ratio during weight loss
social burden. The recently released Access Economics appears to have a number of subtle benefits that may
report claims that obesity (not including overweight) result in greater fat loss and sparing of lean body mass.
nutrition and health
These findings may be related to an increased level of real-world outcomes for society and industry. The food
satiety experienced with consumption of high-protein industry is an important vehicle to deliver the health
foods, as well as increased thermic effects of protein- benefits of foods and healthy diets. CSIRO works with
containing foods. Other benefits that have been ob- the food industry as necessary to achieve both public
served include a greater lowering of cardiovascular and good and economic benefits. Our Adelaide laboratory
type 2 diabetes risk markers such as plasma triglycerides specialises in human nutrition research and over the
and post-prandial glucose and insulin responses. years has gained an international reputation in areas
CSIRO has conducted several of the largest studies such as the clinical evaluation of the health benefits of
showing that higher-protein dietary patterns for weight food and diets.
management have metabolic advantages over high-car- On average only 30 per cent of the research that
bohydrate patterns in overweight people with insulin CSIRO conducts is funded by industry. With respect
resistance. These have been published in the highest- to the research that underpins TWD, the initial fund-
ranking nutrition journals. ing was provided within CSIRO and subsequently by
It is important to note that a variety of dietary ap- the National Health and Medical Research Council.
proaches to achieve weight loss are consistent with CSIRO approached both the dairy and meat industries
metabolic improvements in cardiovascular risk in the to conduct further research in the area of protein and
short term. Moderately high-protein diets can be a safe weight management. This research was initiated, de-
and effective option to conventional high-carbohydrate veloped and conducted by CSIRO. The inclusion of
weight loss diets and may be the optimal dietary pattern lean red meat in the diet ensures that appropriate lev-
for risk reduction in people with insulin resistance. els of protein, iron, zinc and vitamin B12 are achieved
As a consequence of strong public demand to pro- for the widest cross-section of the population. The
vide more information about our research and diet for recommended intakes of these nutrients are difficult
weight management, we hesitantly agreed to embark to achieve in dietary patterns for weight management.
on writing a book on the subject. We assembled a team The evidence that eating red meat, or any single food,
of our key researchers who put together the first draft is a risk for colon cancer is small and does not take into
of the manuscript. account the overall diet and lifestyle pattern. By far the
With the help of Penguin Publishing, the manu- biggest lifestyle risks for colon cancer are having dia-
script was transformed into The CSIRO Total Wellbeing betes, abdominal obesity and a lack of exercise. Diets
Diet, which was released in June 2005. Since then, sales high in whole grains, vegetables and fish also appear to
have outstripped supply and the response has been over- reduce risk.
whelmingly positive. The CSIRO Total Wellbeing Diet TWD is a nutritionally balanced diet: it includes
(TWD) has already been a huge success in Australia: fish, whole grains and fruit and vegetables, all of which
more than 700,000 copies of the book have been sold reduce the risk from cancer. The meat recommended is
after one year and it surprisingly knocked both The Da lean and the amounts are not inconsistent with govern-
Vinci Code and Harry Potter and the Half-Blood Prince ment recommendations. The net effect of TWD, which
from their number-one perch and retained its number- includes balanced nutrition, weight loss and exercise, is
one position for 17 weeks. To keep up with demand, that it has a beneficial effect on health.
the book has already undergone four reprints with We need to point out that this diet is not the only
translations into 13 different languages. The CSIRO approach to weight management. The CSIRO has had
Total Wellbeing Diet has been released for sale in the diet and nutrition information for those with alterna-
UK, New Zealand and the US. Sixty-five per cent of tive food preferences on its website for many years.
Australians are aware of the book and about 10 per cent However, it does represent excellent nutrition and has
of Australian households are using it for both weight been extensively evaluated for its benefits on cardiovas-
control and general health. cular and diabetes risk factors.
Of course nothing popular is ever without some Maintaining a healthier eating pattern longer term
controversy: TWD has been a popular topic of discus- requires an eating pattern that people can adopt easily
sion and some concerns about how the study behind it as well as sustain. TWD has taken research and trans-
www.atse.org.au
was funded and the amount of red meat in the diet have lated it into terms that many Australians can easily un-
been sources of criticism. derstand, as well as shown that healthy eating can be
Over its 78-year history, CSIRO has been dedi- interesting and appealing. The launch of The CSIRO
cated to the application of knowledge and science for Total Wellbeing Diet – Book 2 in October 2006 aims to
nutrition and health
keep people motivated to maintain a better lifestyle as Professor Peter Clifton is the scientific director and
theme leader for obesity at CSIRO Human Nutrition. He is
well as to encourage new users. also professor of medicine at the University of Adelaide and
Associate Professor Manny Noakes leads the Diet and practises as an endocrinologist at Royal Adelaide Hospital and
Lifestyle program at CSIRO Human Nutrition. She also manages Flinders Medical Centre.
clinical trials that provide scientific evidence for the efficacy of He is a frequent and sought-after speaker at national and
diet and exercise programs on health. She is a senior lecturer international conferences and is also widely published
in the School of Medicine, Flinders University, affiliate senior in the area of diet, functional foods and heart health. His
lecturer in the Department of Obstetrics and Gynaecology, personal research interests are in the areas of diet, obesity,
University of Adelaide and affiliate associate professor in the cardiovascular disease and optimal diets for people with
Department of Medicine, University of Adelaide. insulin resistance and diabetes.
Managing the risk of Human demographics and behaviour – with an in-
¢
food-borne illness creased proportion of the population, such as the
immuno-compromised and elderly, more suscepti-
ble to food-borne infections; significantly increased
By Tom McMeekin reliance on food service and increased consumer de-
F
tom.mcmeekin@utas.edu.au mand for ‘clean, green’ foods.
ood safety remains a major issue in the agri- Industry, technology and commerce – with trends
¢
food chain in Australia and other industrialised towards widespread distribution of food from large,
countries. The general public, as a result of centralised facilities; development of mild process-
highly publicised incidents including bovine ing technologies in response to consumer demand;
spongiform encephalopathy and dioxin contamination international sourcing of food, including out-of-
in Europe in the 1990s, have become ‘sensitised’ to the season supply from other geographical regions and
possibility that their food may cause illness. By asso- increased international travel.
ciation, zoonotic diseases, such as avian influenza, have
incorrectly gained public perception as food-related Collective responsibility for food safety
threats and the sensitised state is further heightened by along the agri-food chain
the insidious threat of deliberate, rather than inadver- The introductory chapter in Safety in the agri-food
tent, contamination of the food supply. chain, edited by Luning et al (2006), suggests that a
Food-borne hazards may arise from physical, chem- fundamental change in agricultural and food markets
ical or microbiological contamination of foods at any is the shift from a production to a marketing orienta-
point in the food chain. Of these, micro-organisms con- tion, resulting in a requirement to produce products in
tinue to pose the greatest food safety risk to consum- line with consumer expectations: convenient, less proc-
ers with more than 200 known diseases reported to be essed, fresher with more natural characteristics. When
transmitted through food, with symptoms ranging from combined with globalisation of the food industry and
mild gastroenteritis to life-threatening syndromes. increasingly complex supply chains, sophisticated man-
The electronic surveillance group of the Depart- agement is required to minimise the potential for cross-
ment of Health and Ageing (www.ozfoodnet.org.au) border dissemination of food-borne illness.
estimates the incidence of food-borne illness in Aus- Major exporting countries, such as Australia, of-
tralia at 5.4 million cases a year, including about18,000 ten target distant and discerning markets where con-
hospitalisations and 120 deaths. The majority of food- sumers pay premium prices for high-quality products
borne illness is due to gastroenteritis, which causes 2.1 where food safety is the price of entry to the market.
million lost working days, 1.2 million people to visit a The paradox is that safety has to be guaranteed against
doctor and 300,000 prescriptions for antibiotics. On a a background in which traditional barriers that prevent
per capita basis, the incidence is similar to that in other pathogen growth may be reduced to meet clean, green
industrialised economies. expectations.
It follows that food safety is the collective respon-
Change drives the emerging pattern sibility of all sectors in the food chain, including pri-
of food-borne disease mary production, processing, transport, retail and the
www.atse.org.au
The world is characterised by an unprecedented rate of consumer. Estimates in Australia are that consumers
change in all facets of life, which impact directly on the may contribute to 20 to 30 per cent of incidents, most
nature and incidence of food-borne disease. Important of which are preventable by applying the basic rules of
categories include changes in: proper storage temperatures, adequate cooking and
10nutrition and health
prevention of cross-contamination (see the Food Safety nutritional properties. Alternatively, a series of mild
Information Council website: www.foodsafety.asn.au). constraints may be applied, which collectively have the
same effect on microbial development but impact less
Food safety policy and practice severely on quality attributes of the food. The key to
The concept of collective responsibility along the food achieving the optimum balance of safety and quality is
supply chain is reflected in food safety policy initiatives a quantitative understanding of the microbial ecology
in many jurisdictions, including Australia, in which of foods.
an integrated ‘farm to fork’ approach is mandated. In This is embodied in the concept of predictive
Australia, the standards setting agency, Food Standards microbiology: a detailed knowledge of microbial re-
Australia New Zealand, is currently developing prima- sponses to environmental conditions (expressed as a
ry production and processing standards for major food mathematical model) enables objective description of
industry sectors. processing, distribution and storage operations on the
Furthermore, a common theme is that standards microbiological safety and quality of foods, by moni-
must be based on sound science as the basis of a level toring the environment without recourse to further mi-
playing field to judge the hygienic equivalence of food crobiological analysis (Chapter 5 in Luning et al, 2006).
in international trade. The approach agreed is based Dr June Olley, a Foundation Fellow of the Academy, is
on the Codex Alimentarius Commission risk analysis a pioneer of the concept.
paradigm, which is empowered through quantitative The scientific bases of predictive models are found
approaches to microbial risk assessment. At the opera- in the disciplines of bioinformatics (database con-
tional level, a common approach is the Hazard Analysis struction) and biomathematics (model development),
Critical Control Point (HACCP) concept, through which give rise to predictive software packages. When
which safety is built into processes, rather than relying used with appropriate monitoring technologies (elec-
on end-product testing. tronic temperature loggers, RFID or other wireless
technologies), the prospect of real-time process man-
Science and technology to support agement becomes possible, both in processing plants
food safety management and during distribution, for example using the Austral-
Resolving the paradox of clean, green yet safe foods ian-developed Smart-Trace™ system (www.smart-trace.
with adequate shelf life will provide those companies com). This, and similar systems, will contribute to the
and countries with the ‘knowledge’ with a significant requirement for traceability, which has become incor-
market advantage. The trade-off between foods with porated into food safety policy in jurisdictions such as
superior sensory qualities and microbial food safety re- the European Union.
quires innovative R&D to provide basic and enabling When combined with environmental monitoring
science outputs which, when combined with appropri- and traceability technologies, predictive models will
ate technologies, offer the promise of improved food take food safety management to new levels of precision
safety management outcomes (McMeekin et al, 2005). and provide flexibility for the food industry to resolve
The opportunity for Australia, through strategic R&D, the paradox of guaranteed quality and safety.
to build on its reputation as a purveyor of safe food to Further reading
the world is significant, with the potential to enhance McMeekin TA, Szabo L, Ross T (2005) Connecting science
an already vital export sector in 2005-06 worth $23 bil- with technology to improve microbial food safety
lion and employing 17 per cent of the total manufac- management. International Review of Food Science and
turing workforce (www.nfis.com.au). Technology Winter 2005/2006, 125-130.
Luning PA, Devlieghere F, Verhé R (eds) (2006) Safety in the
agri-food chain. Wageningen Academmic Publishers, The
Predictive microbiology – strategic Netherlands.
research in action Professor Tom McMeekin FTSE holds a personal chair in
When a microbial cell contaminates a food it may Microbiology at the University of Tasmania and is co-director
of the Australian Food Safety Centre of Excellence. He is
grow, survive or die, and the rates at which these events internationally recognised as a leader in food safety and quality
occur are a function of the environment, such as tem- research, with a demonstrated commitment to making research
results available to end-users in industry. He is a Scientific
www.atse.org.au
perature, water availability, pH, preservatives and com- Fellow of Food Standards Australia New Zealand and chair of
peting microbiota. These factors are also the basis of the Food Safety Information Council. He is an executive board
member of the International Committee for Food Microbiology
traditional food preservation methods. When applied and Hygiene and an editor of the International Journal of Food
singly, severe treatments lead to reduced sensorial and Microbiology.
11president’s farewell
Some parting
thoughts
By John W Zillman
I
J.Zillman@bom.gov.au
am grateful to Dr Don Gibson for his invitation icy has never been greater. Whether it be the need for
to contribute some parting thoughts to Focus 143, public investment in research, the planning of national
the final issue for 2006. And I am even more grate- infrastructure, the social impacts of new technology or
ful to Don for having agreed to take up the chal- the formulation of public policy on complex issues such
lenge, now almost two years ago, of turning Focus into as climate change, water resource management, energy
a vibrant mechanism for communication and debate security or education policy, governments are in urgent
within the Academy. It is very gratifying when some- need of ready access to the best and wisest minds in the
thing turns out better than one dared to hope. country. And there is no institutional mechanism that
In Focus 125 ( January–February 2003), I ventured is potentially better placed or better structured to pro-
‘Some thoughts on the way ahead’. Quite a lot of what vide that access than Australia’s learned academies.
seemed achievable for the Academy four years ago has There is no doubt that our largely unseen contribu-
been achieved but some has not, and I will offer a few tion through the role of our Fellows in all of the many
further thoughts below on some of the challenges that institutions of Australian public life is enormous. It was
have not been well met. interesting to note, for example, that in the photo of
However, I wish first to place on record that, for me, the 25 participants in last December’s meeting of the
it has been a privilege to provide the bridge in time, and Prime Minister’s Science, Engineering and Innovation
to some extent also in philosophy and style, between Council (PMSEIC), that was included in the Acad-
the early growth years of the Academy and what I am emy’s 2005-06 Annual Report, six were ministers, 10
sure will be a dynamic new period of activity and influ- were ATSE Fellows and almost all the rest were fellows
ence under the leadership of our incoming President, of our sister academies.
Dr Robin Batterham. A major part of the role that has Where we do not, I am afraid, perform so well and
fallen to me over the past four years, with the untimely where I believe the nation is far less well served than it
death of our former Executive Officer Joy Dudine, has could be is in our capacity to use the mechanisms of the
been to help to provide some institutional memory Academy to harness the expertise of the Fellowship to
for the Academy and some understanding of the les- provide coordinated and synthesised advice and input
sons from its years of outstanding achievement under to the public policy process. I remain as impressed as I
the leadership of Sir Ian McLennan, Sir David Zeidler, have always been by the willingness of ATSE Fellows,
Sir Rupert Myers, Sir Arvi Parbo and my predecessor when asked, to contribute freely of their expertise, and
Tim Besley. often also of their time, to important Academy initia-
Even the briefest survey of the early years of ATSE tives in the public interest. But, as an essentially volun-
is enough to bring home the remarkable influence for teer body whose core functions continue to be funded
good that the Academy has provided on the Austral- by Fellows’ subscriptions, donations and a small gov-
ian scientific, engineering, industrial and public policy ernment grant, we lack the critical mass of policy staff
scene over the past 30 years. and support mechanisms to effectively harness that ex-
www.atse.org.au
I believe the national need for the role played by pertise; and, despite the magnificent job done by our
ATSE and its sister academies in providing objectivity, successive part-time Technical Directors in drawing to-
integrity and balance to the public discourse on com- gether Academy submissions and policy positions, the
plex issues of industry, environmental and public pol- depth, breadth and impact of our coordinated policy
12You can also read
