While food guidelines aim to be simplistic to
reduce confusion; this often
fails. The food guidelines are too general for chronic disease prevention; if
the guidelines were adjusted to be more specific, chronic disease risk could be
reduced.8,9,10
A similar problem occurs within the food
pyramid, which was developed in 1992 by advertising and marketing researchers
to develop an image the consumer could identify with and easily understand. The
pyramid was then widely distributed and has been used as an educational tool,
basis for dietary assessment, and part of policy documents. It has succeeded in
creating high levels of consumer awareness and is recognised by 67% or more of
American adults.11 This wasn’t the first time that government and
industry had made attempts to influence how Americans eat: the first U.S.
guide, “Food for Young Children,” dates back to 1916. And the “four food
groups” developed in the 1950s were strongly influenced by the food
industry—after all, the regulators invited
the food industry to help shape the guidelines. To highlight the strong
influence of industry on US food guidelines, in 2011 the US Department of
Agriculture, the same organisation who created the food pyramid, labeled pizza
as a vegetable because it has tomato paste. Any wonder the food pyramid was so
wrong.
Figure
5. The U.S. Department of Agriculture (USDA) Food Pyramid.
Source:
Chiuve and Willet 2007.12
The 1992 food pyramid encouraged consumers to
eat a huge amount of breads, cereal products and potatoes. This could very well
have resulted in a greater risk of chronic disease (including CVD, obesity and
type 2 diabetes), due to the fact it lacked emphasis and detail on the
recommended type of carbohydrates.13,14 This resulted in consumer
confusion15,16 and poor eating habits.17 Food guidelines,
such as the food pyramid, advocate bread consumption numerous times a day.18
Bread is a contributing factor to a higher glycaemic load, promoting chronic
diseases such as obesity, type 2 diabetes and cardiovascular disease.19,20
Therefore bread consumption should be limited or even eliminated to promote
better health. In the Australian Guide to Healthy Eating21 it is
recommended to eat plenty of cereals (including breads, rice, pasta and
noodles) but we did not evolve eating these foods.
In 2005 the food pyramid was revised into an
abstract version of a pyramid called MyPyramid. This new pyramid still
encouraged the consumption of grains; one of the differences was that it
advised consumers to choose grains that have the word “whole” in front of the
grain name. Sure it changed a little, but not enough to reflect what we should
really be eating. The Harvard School of Public Health made a scathing criticism
of this iteration of the food pyramid.22
In 2011, the U.S. Department of Agriculture
replaced MyPyramid with a new icon called MyPlate. The plate is divided roughly
into quarters, with the largest section again being grains. Dr Andrew Weil,
founder of the Arizona Centre for Integrative Medicine, wrote “there are some conceptual chips and cracks in this new dinnerware.
Overall, I fear another opportunity has been lost to give Americans the best
up-to-date information about what constitutes an ideal diet.”23 Dr
Weil offers as an alternative the Anti-inflammatory Food Pyramid, which promotes optimum nutrition and thus optimum
health.24
Another are of concern is the Recommended
Daily Intakes/ Allowances (RDI/A’s) also known as the percentage of daily
values on the side of your breakfast food packet depending on the country in
which they are used. As nutritional research and knowledge evolves, food
guidelines can become redundant if updates and revisions are not continually
made. The Australian RDIs have been updated only a few times since 1954, yet
the Japanese, Canadian and U.S. dietary recommendations are updated every five
years to match the current scientific research.25-28
By updating food guidelines in line with
scientific research, chronic diseases can be reduced.29 At the same
time, not updating with current research may result in ineffective food
guidelines that misinform and fail to protect the public. An example is the
change in recognising the importance of omega 3 essential fatty acids for
chronic disease prevention. In the 1960s it was thought that both omega 3 and
omega 6 were equally important, however more recent research highlights the
importance of omega 3 over omega 630 and that we are consuming far
too many omega 6 oils in our diet. A food guideline that is updated regularly
can make the necessary changes to promote omega 3 over omega 6; however, if
updates are not made regularly, the health of consumers will suffer.
Recommended Daily Intake/Allowance (RDI/A)
Many professionals suggest that our food is
o.k. because it provides the RDI. This argument has probably led people to eat
poor quality food and think that’s o.k. The Recommended Dietary Intake (RDI)
values were established by authorities more than 50 years ago with the aim of
preventing gross nutrient deficiency diseases such as scurvy and beriberi. They
provide the equivalent of the nutrient bare minimum, the lowest common
denominator for health, and have no relevance at all for optimum health and the
avoidance of chronic illness. Optimum health cannot be obtained by following
the RDI/A. These were passable as a guideline 50 years ago but were never meant
to protect us from chronic illness. Yet authorities now repeatedly refer to
them as the definitive levels to achieve. They are in fact the lowest common
denominator of nutrition and aiming just to achieve them is likely a major
contributing factor to chronic illness in Australia.
The RDI system shows a serious lack of
sensitivity toward individuals with elevated nutrient demands.31 It
does not allow for differences in people’s nutritional needs. Various groups,
including the elderly, people who experience increased physical or emotional
stress, people who are of above average body weight, or pregnant women may
exhibit elevated nutrient demands. The recommendations also fail to take into
account geographic differences such as living in areas with nutrient-deficient
soils or high levels of environmental pollution.32
Socioeconomic factors may also affect the
adequacy of RDI/A values for certain groups. For example, the U.S. Recommended
Dietary Allowances (U.S. RDAs) claim to represent the daily intake levels
sufficient to meet the nutritional needs of 97% to 98% of all healthy
individuals in a group. However, the homeless and poor are not healthy as
groups and inadequate dietary quality has been documented in these sectors of
society.33
Recommended intakes don’t take into account
the interactions of nutrients or toxins—in particular, the synergy and the fact
that a shortage of one nutrient may bring about inefficient use of other
nutrients. While most people know of vitamin C’s antioxidant effects, very few
are aware of the benefits of it consumed with other antioxidants. Extra vitamin
C spares the destruction of other nutrients in the body.
Professor Bruce Ames, one of the most
respected names in modern nutrition and one of the early developers of
toxicological standards, suggests that we need to move beyond the RDI and that
age-related diseases like heart disease, cancer and dementia may be unintended
consequences of mechanisms developed during evolution to protect against
short-term nutrient shortages. In what he calls the “triage theory,” he
suggests that because natural selection favours short-term survival—to escape
from a bear or survive a cold winter—over long-term health, short-term survival
was achieved by prioritising the use of these scarce nutrients that are also
necessary for less urgent, but just as important, functions including healthy
ageing. The nutrients are allocated to short-term essential (urgent) tasks
versus keeping you healthy in the long term and avoiding chronic illness. The
triage theory proposes that modest deficiency of any vitamin or mineral could
increase age-related diseases. This theory has important implications for
determining the optimum intake of all vitamins and minerals, as well as major
implications for preventive medicine.34 Current RDAs and RDIs
provide for urgent short-term requirements only and not the nutrients for
important tasks and optimal health.
In his recent study of vitamin K, Professor
Ames and his colleagues showed that current recommendations for vitamin K,
which are based on levels to ensure adequate blood coagulation, fail to ensure
long-term optimal levels of the vitamin and may accelerate bone fragility,
arterial and kidney calcification, cardiovascular disease and possibly cancer.
So the levels approved for the short-term do not help us to avoid chronic
illness, which is the biggest burden we face in the 21st century. In
another study the same group investigating selenium, reported that the same set
of age-related diseases and conditions, including cancer, heart disease, and
immune dysfunction and an increase risk of diseases of aging are associated
with modest selenium deficiency 35. The overall conclusion of this growing body
of evidence is that optimizing nutrition and metabolism will delay aging and
the diseases of aging in humans 36,37.
Perhaps easier to understand a well-known and
good example of the triage system is the pH (acid/alkali levels) of the blood
and mineral balance. The optimal pH of the blood is around 7.35. If the pH
varies slightly from this level, as a result of eating processed foods which
increase the acidity of the blood, it dramatically affects many of the 90 or so
enzyme functions in the blood. These enzymes literally do all the work, repair,
cleaning up, transport etc in the blood. If they slow down too much we get very
sick and die quickly. To make sure this doesn’t happen the body has a few
mechanisms to keep the pH in perfect balance. The main mechanism is to allocate
or triage alkali minerals like magnesium and calcium from where they should be
working in optimal conditions, such as in the cells and in bones, to balance
the pH in the blood. While this protects our urgent health requirements it
increases our long risk of chronic health conditions such as heart attack,
cancer and osteoporosis as a result of the shortage of these minerals. The body
allocates the nutrients for short-term survival, the “essential” functions are
protected from nutrient deficiency over other “nonessential” functions needed only for long-term health.
It is time we rethink our nutritional advice
to eliminate the vested interests and to come in line with the tens of
thousands of nutritional studies that have been done over the past decades. The
current standards do not represent the scientific evidence that is currently
available.
1.
Ball
et al. 2004
2.
Ziegler
1991
3.
AIHW
2002
4.
Magarey
et al. 2001
5.
Ames
2001
6.
Cook
et al. 2001
7.
Jenkins
et al. 2004
8.
McCullogh
et al. 2000a
9.
McCullogh
et al. 2000b
10. McCullogh et al. 2000c
11. Nestle 1998
12. Chiuve and Willet 2007
13. Willet 1998
14. Weinberg 2004
15. Cotugna et al. 1992
16. Ferrini et al. 1994
17. Grifford 2002
18. Nutrition Australia 2005
19. Davis et al. 2004
20. Villegas et al. 2004
21. NHMRC 2003
22. http://www.hsph.harvard.edu/nutritionsource/what-should-you-eat/pyramid-full-story/index.html
25. Kris-Etherton et al. 2000
26. Cobiac et al. 1998
27. Bush and Kirkpatrick 2003
28. Guthrie and Smallwood 2003
29. Jacques and Tucker 2001
30. Holman 1998
31. Gopalan 1997
32. Kirchheiner nd
33. Wiecha et al. 1991
34. McCann and Ames 2009
35. McCann and Ames, 2011
36. Ames 2010
37. Ashutosh and Ames 2011
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